if you support community control, what does that mean about how you make decisions for your organization. if you say you are about something then ask yourself how are you are about that as an organization and an ally. >> practice makes perfect. >> let's open it up. >> let me get a sense of how many people want to chime in. were not restricting this to just questions, i don't like that idea. if you have a brief comment, you can have a chance to make a brief, a question. i want to see a show of hands of how many people initially have something to contribute. to this person goes first and i'll just call out a few people

and then david and then you and then somebody in the back there. will start their. >> thank you so much, this is a pretty intimate space so please don't take my not standing as disrespectful or anything. i'm a senior at the university. used the specific language of anti- blackness. martin just use the language of black women and danae, what i love about your work, you took the analysis a step further, were now recent ring black women, we're person and radical feminist ideology. we are sitting in a white lead ally in this movement. can you talk further about the importance of the social change

theory? >> thank you for asking that question so i would like to say that movement for black lives is committed to what we call a black, queer, feminist lens. it's really the practice of intersection alley, that is is that we are comprised of multiple identities so i am a black, queer woman who is the product of an immigrant father. there's so many identities that i made up of and that then subjects me to multiple types of regression. that is not either or, it's not additive, it is multiplicative. to recognize being people's self and what that means on how they can and cannot operate freely in the world.

we have to be radically inclusive in our analysis when we think about our policy ideas, when we talk about programs that we want to start and how we want to treat each other. i meet a person after asking them their name i'm going to ask them what their gender pronouns are so i don't inadvertently missed gender someone. it's really just recognizing peoples whole humanity and being intentional about how different people are differently affected and differently oppressed in society so that our vision for freedom and justice in the world that we want to live in, everyone is included in that. censoring those at the margins, it's by doing the that so that everyone else wins. if the black trans- woman who lives in the most impoverished

neighborhood is free then i know i am free to. it's really the idea that all of our liberationist tied together because we recognize the multiple identities we are made up of. >> thank you for all you do. i have a question about accountability. we hear that word a lot. you can figure out how to do that in individual interactions but for me i was wondering if you talk about when it comes to inter-organizationally, what could what could that look like? i can't even imagine. >> i think it can stem a lot of different topics and so i don't want to take your question down a different path if you have a specific thing you are talking about. about organizational accountability? >> yes i'm taking the organizations holding each other accountable and work toward different -- what way can that happen?

when it comes to accountability, real accountability for talking about organizations that work together in order for accountability to happen you have to have a relationship. i cannot hold someone accountable in an authentic way if i'm not in relationship with them. goes back to shared values and trying to identify our bottom lines and things like that. you have have a starting point of trust in a relationship in order to hold another organization accountable. that's the first step. it is in building that relationship, identifying how we want to work together that someone needs to be held accountable. then that accountability looks

like whatever is defined early on. i think mechanisms of accountability, you have to offer the whole -- we have to have an understanding about what it means to work together on what were trying to achieve et cetera. clear when you violated that or transgressed against fat and you already know what's coming if that's the case. it's really hard to have a blanket mechanism of what i come ability looks like because i think it has to be appropriated. >> thank you all for being here i think of going to pick it back a little bit off this question. i am in basic agreement to most of what you are saying so i think this comment is a reaction and not a criticism.

certainly the conversations in public dialogue has changed over conversations about race, but i asked myself by what measure. for instance in an african-american community, the papers and records use the term that were waiting for 2030 or 2040 when our young people face realities where they are not being report to as a minority and yet we don't challenge the criticism or attacking the community where people feel distracted. if we challenge things and allow people to be underprivileged. people lose jobs, the traumatized. they don't have a community that supports them up and support

them in physical and nonphysical ways. the reality that we do need full-time people who are paid to do the struggle as well as the community as a whole. modeling for children, let's model that not because of the mainstream media, but let's model it so they can internalize it and be creative in their own right. those are just some comments just be quick. >> think even the folks who worked on this document and someone who literally loves policy, i think it will also not save us and it is part of much bigger organizing effort struggle think that is a

question we have, is this a poverty issue. [inaudible] i think it's part of the way we need to change. [inaudible] >> i think some of the things you mentioned some of the very things we want to amplify to the platform that we have. yes, sure, this is a policy document that a lot of the solutions that were calling for, it doesn't necessarily mean that they are engaging in policy issues. you mentioned, i can think of really gory organizations in chicago and trying to build

alternative means and that work is happening and will be amplified. the more that we can amplify it, the more we can take things to scale and spread across the country. i do think anything in disagreement to what you're being put forth but thank you for uplifting that. we can continue to take these things to scale. i'm of the belief -- if you say that, minority has, it denotes that you are less than. >> my biggest problem here in washington, that i'm associated with media but it's media that looks like me and that's part of

the struggle. >> thank you for that. >> we have some people with questions that are written down but will go to people have their hands raised first. one were dealing with social justice, how do we keep individuals accountable. the type of person i am, i might be a little cold when trying to keeps will, how can you have a

discussion and shut somebody down when they're not acknowledging or -- >> i think that's a good question and it's a legitimate challenge. i'm immediately thinking about creating a call-in culture versus a callout culture. especially in the days of social media where it so easy to create a status and attack somebody in it, whether the transgression is legitimate or not, i think defaulting to something very public, how dare you manner can

be conducive to that person sitting down and not really hearing what they're saying to take and or not doing whatever it is. when i say call-in culture, it's really taking that to be intentional about how you approach someone. when you take the act of calling someone in, it can be knee-jerk, it has to be calculated and intentional to say how is it best that i can communicate to this person, how to best checked themselves in the future without embarrassing them or -- you have to do some checking within yourself to do that and also going back to relationship and you can't really do that if you're not in relationship with

them. i think that's really a starting point. >> thank you for a really great. any questions about reform regarding the decree against the boston police department? could this be an opportunity for some of the reforms in your platform or do you think it's going to be more like what you said before like increased budgets and more body camera or could it be an opportunity, i just wondered what your opinion was. >> when i think about police reform, i automatically think about an op ed and it's called

police reforms you should always oppose. it is a list of about eight criteria that you should ask yourself when the reform is used and you should think about it and say that's not the reform that we need and the things you should say that we do need. police reform that uses terms like community policing but still exist within police departments or whatever, anything that is technological like by the and other types of policing, it also means that more money is going to those departments and it's likely to

be a disservice and increased surveillance rather than to hold police accountable. on the topic of body cameras and how many police executions have you seen? how many of those resulted in any kind of accountability. why should it be pushing these false solutions? i encourage everyone to google that article. consent decrees, whether they are helpful, if that's even the word to describe it or what are the recommendations coming out of the decrees because they can

vary within. >> amen to that, i think the other thing i would say his two thoughts, so i know obama has started the investigation, there's a need to articulate the problem. they use excessive force, they profile and there's no community control accountability. the articulation of that is important. we have a very long process and it helps connect with folks who may not be part of that movement. i think in that way it's important. what is disappointing about these dissent decrees is that there are literally hundreds of millions of dollars every year. with no accountability in the conversation, none of those

things actually matter with doj performance. these programs are deeply invested in the status quo as is we know for that you are filing basic human rights, would not give you tax parallel to do that i think it would be an incredibly exciting moment for the doj and investigative power to say we have these findings and we are not going to continue supporting these departments that continue to hurt people. i read those reports and find

them interesting in the diagnosis and scope of the problem but wish there was some money to back it. everybody put your money where your mouth is. >> i'm in a put the organizer hat on, while that would be nice, i don't see that happening with the doj. we say the police aren't instrument of control. looking tree in the global economy, there are reasons why the department of justice is increasing militarization and all that kind of stuff and why there's more necessity for control. the powers that be that we often appeal to, they need the police. the police are out of control even by their standards but they can't do anything about it because they need the police to

control us. we are talking about challenging the system and doj as part of the system and the police protect the system and there's a catch 22 there. we want to raise up, in the vision demand talking about community control of police, that that doesn't mean we shouldn't be pushing for things. i'm not disagreeing, we should be pushing for thing with an understanding of what it means when we upped the ante and having a strategy that's long-term. we need to think about taking our struggle to the international level and the united nations and all that my personal assessment, maybe i'm, the department of justice unwilling and unable to provide

red dress for black people when it comes to holding the police accountable for murder. anyway, a lot of people out there have given some written questions and we don't want to neglect them. i'm want to read them all and if you can maybe take notes on them and answer them. there might be more coming in and we want to go back to the people. we don't have a lot of time. this first one is the fossil fuel and climate change industry both affect black lives first --dash what are some ways you see black lives matter and climate justice movement intersecting or should intersect and then, let's just do them one at a time.

>> i think there's a lot happening with folks down in the golf doing incredible work on organizing and activating --dash literally they are dying. the climate changes killing people. also there's a lot of organizations. [inaudible] they see themselves -- i don't think it's separate. it's exciting to meet folks who are at those intersections and i hope there are more conversations. >> the next one is what role can celebrities and athletes who are people of color or allies play in the expansion of expansion about those vulnerable in the community.

>> the motto of the day, putting your money where your mouth is reminded us of michael jordan in his recent donation to the eye ecp, $1 million donation to their community relations institute or whatever it's called and i'm just thinking about the many different ways that $1 million his vast monetary resources, how that could have been leverage in a much better way. thinking about athletes and black athletes in particular, i think their platform -- they had

asked themselves in the same way were talking about ally organization about what is there skin in the game and what are they willing to put forth and put on the line and what do they believe in? think they might be making a statement that's beyond top gun violence really be critical about the system in itself and not really reporting this black on black crime, but really being critical and start with critique and leveling platform and take part in the action. just because you are an athlete or other celebrity doesn't mean you can't get your hands into. we all know jesse williams, i think it's a good example for how you could use your platform

for doing some good. i think some of our black athletes that we love so much can be really self-critical about how they can engage in. it's an education process and a lot of them need to be educated. that doesn't mean that's where he could be if you spent more time reading documents like this i think there's an opportunity but a lot of the athletes, celebrities, there's a huge education process and they would have to be willing to do that and talk about the sacrifices that many people talked about. the more political they get they might face some backlash. it's creating an opportunity for

athletes and celebrities to be a little more conscious. how far they go is really hard to tell. the power of having celebrities be a part of the movement, there is great power and potential there i think it starts with them being educated who could really provide them with the real knowledge in a base of what are the issues and help them figure out what they can do about it. i would add to it. >> i would add to it that the most powerful force we can add to it it's to be organized. they can organize celebrity athletes for movement of black lives matter. coming together protects them from an individual attack and it strengthens the impact they can make. think it's very important for them coming together on the arena that they can work in and figure out what they can do together.

the last question, we want to hurry up. recently several members of the faith community have expressed a lack of understanding and their role of the racial justice matter. what would you say to the faith community to define your expectations or what you may desire from religious faith community to move forward. >> i think the faith-based community has a long history and movement link. mlk is somebody that everybody knows and thinking about his role in the church and just like today, i live in chicago and i'm thinking specifically about the united church and how supportive they are and hundreds of organizations in the movement

both in terms of like space, money, people, churches and congregations that are made up of people and the thinking about the values of multiple regions. the value of religion, thinking about how it space and social justice, how can churches or whatever organize and be in service of that? i think that comes out many different ways. there's a lot of conversation we are ready had about being able to organize people who are already organized in a sense that could be joining pain and i

think that can look to history as a proxy for that. it's not a new concept, something that has happened before and it still happens today. i don't it has to be a revolutionary idea. >> i think there've been folks have really shown up and what get set in church on sunday has shifted in the past few years as well. that has been very powerful. the pulpit, i think we should organize and think about how folks are organized, what are we saying to people? in matters in terms of a believe and that's important too. [inaudible] and that's incredible to see.

: that is as place where, blackness, is really concentrated, in every quarter, in columbia, south carolina. so, churches, can also be a place where some of the that's we think about as being ann take they take cal, that we have been talking about today, the church

is the primary place to be challenged. the church, and other religious institutions, has a responsibilities, if you want to be supportive of this movement and what it stands for. a responsibility to deconstruct, anddismantle it. all of these things that we're up against. because we're not just against these big mac crow systems. we're also up against i de on guys, that oppress us, that we per pef wait against each other. >> i like what you said, in looking at the history of the church and all faith community and movement. that's one thing, that they can do, is study that and try to live up to it. and, study their own principles,

of their faith are intersecting, with what we're trying to achieve. so, we, i want to go to maybe a couple -- is there anyone -- okay, let me get you and i thin- >> all right. four more, because you got to get, 30 seconds, to get your questions. how about, each of you, present and then we'll try to wrap it up. and answer all of them at one time. >> you mentioned that, the vision for black lives has created, by a united front and local elections are primary. i'd like to hear what you think about the vi built tive black political party. >> talk about gender equity and race equity, and, black women get overlooked, and, this panel shows that women are more

radical than the men. [laughter] >> that's the goal. >> just be quick. we talk a lot about organizations, but my question is a process oriented. how to do that without putting an additional burden on black folks. >> that was more after comment, than a question. i think it's important that we have the conversation, about lon lon give visitty, more of a comment or sincere extension to, have those conversations. when you have such growth and movement such as these, there is the concern for protection. and, just, someone else was in

those kind of conversations and i want to remind you, to have them. that's tough to remind yourself. but definitely do that. we have to have lon give visitty.when i'm thinking about political power i don't necessarily mean that to be interchangeable with that. because i think that, the path, to political power has to be cross cultural and it has to be collaboraative. and i think that the idea of one black political party, that's,

that should be representative of all black people. so again, my comment is not in opposition to that idea. but, i don't think that the should be the sole goal. >> yeah, i do believe, in talking about the struggle for black lives matter, in practice and how that should be reflective in all segments of our lives. it is black led. but that's not like at the exclusion of over people that don't have black skin. so again, i think, that's not a bad idea at all. >> i think it's an end, either or. >> gender equity, i want to say

that that has been a key theme in this whole panel. i'm not sure,000 answer that directly. but i will say, this platform is complea hennive, and, i'll be accompanying policy briefs t. can be a lot of reading and i encourage you to do it. at the very least i want to make sure that i highlight the fact that, gender, and race equity is like at the crux of why this platform exists, and in us challenging ourselves, in service to challenging the world, how we think about gender, and, race, when we're talking about all aspects of our life. so when talking about the economy and workers, really

making sure that we uplift domestic workers, and the caring economy. women's paid and unpaid labor are undervalued. that's definitely, not just included but, in this document. so, you know, that's an ongoing value of this movement that i think that we address. >> i think, maybe you should take something. >> what you just said about the equality. we should be open and imaginative and, that's not the goal. i think it is part of the conversation and i'm down. i'll copy the answer.

that was important, it was a lot of black women who were in that space, so that's an exchange. >> and, i think that we tried, and, hopefully, did. process, of the organizations -- i think that a lot of the process is, out there. >> so, i think that, a real need, they need to fund and support organizations and, the thing, it goes to the last few years has given the folks, how you do that. and i think relationships, this is about accountability. and the rips that you have and build, are essential. thank you. i think like, the idea taking care and sustaining, in terms of strategy, and health and love and self care.

it's essential. thank you. >> also standing up for racial justice, i think it has has a lf good resources for how you might do that. >> thank you for asking that question. i think the only thing i would say about organizations, is that, part of the reason why, as a fellow here, i wanted a conversation like this to take place because i think institutions like this, and many others, that are white led, they're focused on justice issues, need to, as you said, be comfortable, understand these issues. and really think about this stuff and make this a core of what they do i think organizations need to be going through racial bias tracker, win the organization.

employment of the staffing, it's fundamental to how they see themselves. >> we're talked about, some demographics. and those are steps that they need to take. i'm not the biggest fans of politics, and whether they're white or black, there's a lot of problems. but, i definitely hear what you are saying. i think it would be a good thing, with a lot of help and support, so it wouldn't turn into so many other political parties. >> i have on here, give you some closing remarks. we're out of time. one minute thing? i didn't want to only have you answer the questions and not do any kind of wrapup. >> so just to sum up, thank you all for being here. i encourage you all to read the

platform at policy -- if you are part of a organization that's doing the work, check out, take action page and if you are interested in learning more, please visit the website. and, i want everyone to walk out of heir asking yourselves what side are you on? how are you taking that into practice? >> i would say that the, i think it's so important for people to know all the difference organizations, that are part of it. because there are so many amazing organizations, that we don't hear about. and the facts, they come together to put this document and you have to get to know all the individual organizations, and the amazing work that they're doing, and, this is a way, for a lot of folks, then i think that this has been a great two hours spent together.

>> i think, yes to both of those things. i think also, thinking about how you plug it in, in dc, and other folks, if you are not from dc, and, i think it's like looking at them, locally who are doing this. and we see, walk in and then, control by adams, and, thinking through like, all over the country doing incredible work. >> solutions will be at the -- hold line and do it. so i encourage everyone to do that. honored to be here. >> max, is a member, and, the only thing i would just say is

that our struggle is international, so when we talk about black i., it's black african. and if there is -- in unity that is strength then we have to take our stuff international. and identify the forces against us. >> thank you for coming. and, i hope that it was rich for everyone. [applause]

>> all the event, that led to major opportunity and relates that to what is happening now. there's so much going on, the spread of technology and two thinks happen. we can either screw it up or use it to create hundreds of years >> i'm a writer, and i share it, so, when i'm not reading i'm writing. >> you have and book t.v. has covered you, talking about your books. isn't there a book club that you are involved with. >> i started something called the congressional writer's cow cus. 30 members of congress who just

enjoy writing and we do workshopses, and, we talk about their process and it's just a refreshing group of members. >> i thought i would take a little break and i'm reading, and, you see the movie, the marshon and then the man in the old and i didn't read that one and i a guy named phillip dick, so, those are the light things. just find up a biography of the wonderful one on washington. it's long. >> well, a funny thing happened on my way to having time this

read this summer. speaker ryan asked knee co-chair the platform committee. some of the time i had planned to spend is now going to be consumed by reading the republish land platform. for fun i'm going to go back and finish a book i started call 7 miracles that saved america, why they matter. cry chris stewart and his son. he's a fellow member here. >> how the west won, the neglected story of the triumph. and, i'm hoping to get through it. >> and maybe some books about my district, like the history of the county that i was just given

>> i'm looking forward to reading alexander hamilton. i'm lucky i got to see the broadway show. >> i tell you, it really did whet my appetite to see how that was transposted. so, during the break, good opportunity for knee sit down and enjoy t. >> book t.v. wants to know what you're reading. tweet us your answer. or you can suppose it on our facebook page. >> a look now at the dawn spacecraft. a dwarf planet, and, destinations.

>> hello, welcome to the lecture. this is an event to the public, to learn more about our mission, and to also get up close and personal, with our scientists and engineers, and they do all the hard work. so, before we really get started, a couple of things, please turn off your cellphones, and silence them. >> please go over to the microphone so we can hear your questions. and we're recording this.. nasa's mission and this is the first spacecraftto for the planet.

now, this has been an incredibly successful mission. last month, don was award the colier trophy. >> who better to talk about it than don's chief engineer and mission director, mark raymond. [applause] >> thank you. >> to everybody who is watching this at home, sorry you're not getting all the free money that's being given out to all the people. but thank you for your interest as well. >> i'm going to tell you about the dawn mission. >> here we are, before i

startling you about the dawn mission, i want to give you a little bit of context. so, let's take a look at what they knew about the solar system in 1,800. here we are with a conventional view, looking down on it, earth, mars, jupiter, and apart from an occasional comment and some moons, this is what they knew about it. your it could not have been drawn 20 years earlier. >> so, this was a modern view of the solar system in, 1,800.

now, for fun, this is the arrangement of the solar system, as they were known then, showing you the locations of the planets today, on this very day. so so if you imagine being here on earth and earth rotating this way then you can see just after the sun has gone down, mercury and venus are near the sun and, in fact, maybe you can just catch a glimpse of them, but the you can see jupiter, mars and saturn, in the evening sky. >> when you leave this evening. mars and saturn will be very nicely positioned with the moon between them. so, the mars will be just a little bit below and to the right of the moon. take a look at it.

the planets won't change that quickly so you can see it. tomorrow the moon will still be nicely positioned. this is what they knew in 1,800. and then along came this fellow, a math make tish enand. >> shears series, and, is often depicted with her harvest bounty and her crown of grains, and, in this case, the artist has chosen to depicts her with a size. different artists use different implements, but, it's the same idea.

in fact, if you had cereal this morning than you have a connection with the good goddess. >> here's the same chart i showed you had, the planets as they were known and here's the planets as they were known in 1801. series fit into this gap. and, for two he generations was considered to be a planet. so, that makes as nice story, and, happens to be true. and then along came this fellow, who was trained as a physician, but was a fantastically productive as tron no mer.

it is not as well understood, in class a cal meththol guy. she was worshiped in the home. so there are fewer surviving records, as to how she figured in. you perhaps have heard the very begins, but i'm referring to the goddess herself. she's rarely depicted in art. when she is, she has this very stern look on her face, but one of the things i hope to convince you of, is the solar system is a happier place. so that's what he discovered and

here's the same picture, i zoomed in so jupiter is the outer most planet and vest take fit into it it was considered te a planet. if you had come to the lex sure, 200 years ago, and i don't know how many did. [laughter] >> there would have been two interesting differences about you. one is your home internet connection would be slower. but the other is you would have learned in school, that they were planets. because that's how they were known then. but, science and technology advanced and by the middle of the 19th century, more and more bodies found, and it looks like

this. confirm later on, that i have added 10,320 individual dots to this are the chart to show you the location. we know about many more asteroids to that. >> fy showed you all of them, this would be nothing but a yellow green mass. but the point of this is to show you that this part of the solar system, which we call asker road belt, is very different from the inner solar system. and, in fact, if we zoom out you can see more clearly. there's something different about this part of the solar system, from the inner and outer. so that raises the question, why is that.

well you're a good audience, the next part is going to be to try to answer it. i have to take you back in time a little bit before his 1801 discovery. i have to take you back to the dawn of the solar system. i'm telling you, about the dawn mission. [laughter] >> so, this is the photograph from hubble space della scope of a large cloud of gas and dust, sampling ga terry us, this is sg that you can see. what's happening is, off the top of the picture, is a brilliant star. the light of the star is so intense, that it is a shines down on this cloud of gas and dust, it is blowing this

material. now you have a swurlg cloud of debris with material flying around. sometimes these particles will hit and break apart. other times, when they hit,

they'll stick together, and kue see that happening with these two particles here. another hits and sticks to that. and another one. gradually, these grow larger, and larger, and larger. they grow larger to form words. in space, they form rocks. >> they formed, six years ago. >> however, when massive jupiter formed, it was so intense it interrupt they had process.

we want to exfloor to get insights into processes that were act at the dawn of the solar system. because we believe these bodies retain records of what was going on, as planets were building. these things almost made to full size planet status.

>> can look at all asker roads and two of them are so small that i had to put boxes around them, to convince that you there's something there, compared with vesta, and you can see that series and vesta are different. they're nothing at all like these chips of rock. >> so, we can look at it differently. and here again, a die amount mitter of 350 miles and series, 600 miles. >> they went by, particulars years ago, and matilda, and in the interest of full disclosure, i have exag ger rated, it, so

you could see it. that shows us, that it is not all like it. they're closer to the scale of other solar system objects. and, i'm sure you remember, in, 2006, created a new category, dwrn planets and oh, everybody thought how could earth be such a bully, and why were we so inconsid rat and think about pluto? well, whatever you think of that decision, when that category was created, pluto was the second object to have been discovered that fit in that category. series was discovered, 129 years earlier. so what this shows me is, once again, vesta and series aren't just chips of rock. they are worlds.

and one of the things that i think is so cool about this mission, is we're truly exploring uncharted worlds. what could be cooler than that. these are the two largest, prior to the dawn mission, the two largest worlds in the inner solar system. >> so, they have much more surface area than is suggested, even vesta has more than twice the area of california. so we can go in the third dimension and compare it, with that of the continental united states. not as big as the united states. but it's still a big place. it's 37% of the area, the contiguous united states.

when you just think about how vast and varied and beautiful the geography of our country are, is suggests there's an opportunity for a lot of different things to see on a place like this. i should point out in the interest of being clear, this is not the correct color of the united states. so that's the size and now, let's take a look at this alien world, that dawn has unveiled, and, it looks like getting a little saturatedded and there's a great deal of variety on the

surface, and one thing that stands out, these bright features, like this one here, and this is one of our photographs, of a crater, with these bright feemp yours, just glowing out. this really just looks like these mesmerizing lights shining out, just guiding the way for a spaceship from earth, just, invite it go to go in for a closer look and that's what we have done. i should say a lot of people, when they saw this, asked have had these could be the lights of an alien city? i think people should be embarrassed to and a question like that. this is serious work. i think that betrays, it and as we're sending a spacecraft, how can we know they live in city

says in. [laughter] >> they could live in rural communities and they wouldn't have light. so, those kind of questions, i think, don't respect the way that we advance our knowledge. so, again, i don't know how you can see it, in addition to the shape of the distribution, i hope you can see there are many fractures here, which i will come back to in a moment. but, this picture we just got, from dawn's lowest orbit. and i'll tell you more about, what we now understand to be going on here. let's just have running here for you, sites, and, i'll add the diameter and series being named, and, all of the features on series.

they are named for gods for agriculture or festivals and you'll see that in the captions. >> slammed into the surface. and excavated this crater. >> underground, there was salt water. think of this. >> on the surface it would freeze and transform from being a solid to a gas. it would escape, depart and they would leave behind the salt. so the bright features, there,

and elsewhere, including on this strange mountain, these bright features are salt that is leftover from the supplemaking of the subsurface salt water one of the things that's intriguing is that, salt should not remain bright for 80 million years. so there still remains a question how it can stay bright until now. so, that's suggesting the current active processes, occurring, on series. so, this crater, or vera, and, there are ones larger than that. one of the things that you can see, well, could you have seen is the variety of terrain, inside. this one, is a relatively young

crater, very fresh features here which suggests it hasn't been exposed to the rain to erode t. still not the largest crater and look at these strange fractures in the surface. it's another indication on geeolo guy, and, it has many fractures running around the interior here, which, have yet to be fully explained. and, continuing to orbit series, and, take pictures. >> right now, it is orbiting --

dawn, i should say, closer to the surface than the international space-station is to earth. so, as long as there aren't any tall trees we'll be okay. [laughter] >> thisthis is the power that we have to send a spacecraft to a dwarf planet and get down, to stud dit neighbor e nature of this alien world. that's a quick overview of series. and now vest ta. this is the best picture we have, prior to the dawn mission. and, if we look at the shape, follow it, starting here, going around like this, and it looks pretty much planet like until you get down to here, and you would expect a smoother shape here near the south pole. they concluded, that what we're seeing is a big ater here, big impact crater with a mountain in

the center. and you have seen pictures, of large craters, with a mountain in the center. maybe you saw them in the pictures that i just showed you, or you have perhaps seen them, from mars. and the reason for that, the way you make a crater, tau a big piece and it comes screaming down into the surface and it hits it with so much energy, that the surface melts. and, it flows away from the impact and then, goes back. as it sloshes back it solidifies, and so the mountain is, to me like a snapshot of the process. so i want to show you a artist's concept, of how it may have formed, from the impact of a big beast of debris.

here's vesta before the impact and now after. it's sprayed a huge amount of material. >> you may have seen a piece of vesta.

>> you also know we have it from the moon. but we very far, far more meteor rights from vesta and those are the only three bodies to which we have linked specific meteor rights and we have it from vesta than flat moon. even accounting for the more than 800 pound he was material, that they brought back from the moon.

there's network of 90 canyons, near the equator that rival, the grand canyon in size.

these are now understood to be a result of the big impact here, that almost completely destroyed vest ta. it hit with so much energy, that that energy reverberated, inside vesta and broke up the ground, hundreds of miles

>> we fly and mob it, to fling the spacecraft, and, as a fully responsible and other wise intoostution, nasa and jpl believe in conserving energy and in order to speed up the spacecraft, mars had to slow down. so, mars orbits the sun more slowly now, and, then it did beforehand. if you are keeping track, mars moves more slowly by a rate of 1 inch per 1850 years. in july of 2011, dawn got vesta, went into orbit and we spent 14 months there, studying this unique body. and then we left and spent two-and-a-half years more traveling which we reached in march of last year. the spacecraft is there, and it

will stay there, forever. at each body we me a set of measurements and we take many, many pictures. you're visual creatures and we all love to see neat pictures and i have 140e7b you some of those. we also take pictures, in stereo, at different angles, in order to make a map. that's how we're able to show you, the animation, was the accurate topography and how i was able to tell you the height of the mountain, on vest ta. we also mapped the composition, that is what kinds of adams are there? >> which items on that table, o cour these bodies? we mapped the minnals, that is what kind of rocks are there? that's how we know that bright

material is salt. we also measure the gravity field because that tells us about the structure of these bodies. how are they organized inside. one of the things we learned is, that, it has the dense ironic kel core, surrounded by a a man dispel crust. similar to earth. >> once again that illustrates these aren't just asteroids, in fact, in most ways, vesta is more closely related to the planets, the rocky planets, than it is. it's more like a mini planet. we also searched for moons because these objects are large enough. and so as we came in, towards vesta and series, we looked for

moons. interestingly we didn't find any, and we don't know what the expirveg -- dawn is the first one ever, and, it's also the first spacecraft to reach a dwarn planet, and, it's also the only spacecraft ever, in more than 58 years, the only spacecraft ever to orbit any yet

it had never been tried, prior to the dawn mission. >> but it has never been tried before. so that raises a question, why is that? >> why have we never tried? >> thank you for dishag question. the reason is, because until recently, they were confronted with the problem of they were just trying to do something, that was beyond their capability. it was just too hard with the technology that was available. so, here, jpl i got together with some colleagues and we asked the question, how can we travel around the sun more easily. and, our answer to that was i on propolicytion. >> if you are like me, the

fighter that was used to fight the members of the alliance, in the universe, it stands for twin i on engine. >> and, this was what he could think of. one of the things that's so rewarding about working on projects like this, is the opportunity to turn that science fiction into fact. so here's dawn using its engine just a little bit more than one year ago, thrusting with its engine as it goes into orbit around distance dwarf planet. this is the photograph after engine operating in a vacuum chamber, and we have one, and

you can see, it does produce this cool blue glow. the reason for that is because the propellant, like helium, heavier, just happens to glow blue, like knee on, and glows orange. it is ten times efficiency of chemical propulsion. >> now it's interesting, although the engine is very, very efficient, with only a small amount, through the engine at time.

so, although it is very efficient the thrust is very gentile. and, i'll do it, and this is safe. you can do this yourself at home. that is, the engine pushes on the spacecraft as hard as this single piece of paper, pushes on my hand. >> so, it would take dawn, two weeks, at full throttle, to expend just. >> that's why it is so gentile. if we thrust for, it would take four days to go from zero to 60-miles-per-hour. didn't exactly evoke the concept after drag racer. but, instead of thrusting for four days, if you thrust for a

week, or a month, or a year, or as dawn has for more than five-and-a-half years you can achieve high velocity, so this is what i like to call, acceleration with patience. i'm a very patient guy that is great way to explore the solar system. this is the key to what has allowed us to undertake this mission which once again would be impossible. excuse me. now, i told you, that it has been around in science fiction for a long time. because of the constraints of time i can't give you the entire history, but i can tell you, that it goes back quite long ways. but, let's focus on dawn, which, you can see here, and the first thing you notice is, it's

dominated by these huge solar arrays. when we launched in, september 2007 the solar wingspan was longest. because we go far from the sun. so we need a large area of solar cells to capture enough of that sunlight to produce power. in particular, that engine is power hungry. takes a lot of energy to accelerate t. so, the solar rays, are 65 feet. that's the distance from the pitcher's mound to homeplate. if the full size spacecraft were here, with this solar ray here at the front, this one would reach almost all the way to the back. it would reach to the people who are sitting at the back of the room. and, for those who are watching thorks your laptop, that's a

long way. >> so this is a remarkably large spacecraft. for another sense of scale, this is our main antenna, and, this is how we communicate with the spacecraft. this is one of our engines here, and here's a second engine and, there's a third engine, so we do the "star wars" fighters one better. so, that was an artist concept and here's as photograph of it, when it was being built here. this is one of the solar ray wings and these are folded up because you can't fit a 65-foot wide spacecraft. so when the spacecraft gets into space, after the nose cone, and, into space, after the nose cone releases, or separates, and releases it, they open up and, to me it's like a big dragonfly

taking flight. i think that's neat. it has 15,000 little holes in it, through which we shoot the ions. because of his greenish, bluish color her, he has a cosmetic affection and gets a kick oust being included in my public

preparation, and when i go home and tell him not only did a bunch of people here in the pasadena area see him but people watching at home on their laptops will see him. he's going to think that pretty cool. but back to the spacecraft. here's the main spacecraft structure here. here's the five-foot diameter an ten new hampshire here's tom. and this is one of the two solar array wings. each individual wing at 27 feet is the width of a single tennis court. a very large spacecraft. think they're neat things to look at. and people in the room can look at historic and fascinating spacecraft. to me, neater than what spacecraft look like is what spacecraft do. so i'd like to talk about what spacecrafts do because we use them to go far from home.

this, of course, is home. and to the accuracy i can do powerpoint, this is low earth orbit. it's space but not very far away. not very far away. in fact from here to san diego, is comparable to the distance from the surface of earth to lower earth orbit, and somewhat farther than that. this where is many, many spacecraft, including the space shuttle. the international spates station and many others work. space but not very far away. so, let's zoom out and now introduce what is called geosin crow news orbit. and a satellite takes 24 hours to go around the world. we have a satellite going around the earth in 24 hours and earth itself rotating in 24 hours, then the satellite is always over the same point on earth. or from the point of view of earth, the satellite is always in the same place in the sky.

and so that why this is a very convenient location for weather satellites, communication satellites, or other satellites that you want to have either have a fixed view of the surface of earth or from our perspective on earth, having a fixed location in the sky so you don't always have to reposition your antenna on the ground. and almost 22,300 miles away, ore bit of is a long way away. a long distance, far even compared to the diameter of our planet. and in the more than 58 years of sending spatecraft or satellites into is a ther who e overwhelming majority have gone between low earth orbit and geosynchronous orbit. let me move the same setup here and i'll put the moon where it belongs at the same scale.

the moon is ten times the distance to gee cinco news orbit. the moon is far away. you may have heard stories told by our ancestors that long ago in the late 1960s and early 1970s, 24 men traveled the distance from the earth to the moon. but people don't do that today. people don't do that. people go -- what that tells me is this picture is of the scale of the entire range of first-hand personal human experience throughout all of human history. it's all contained in a picture of about this size.

and dawn passed the orbit of the moon the day after it launched. we launched september 27, 2007, and on september 28th we had the moon in our rearview mirror. so now late introduce the next scale here, which is earth's orbit around the sun. and as earth goes around the sun, it carries the moon with it. so let bring the sun into this picture now. this is the sun. and to the correct scale, this is the orbit of the moon, and this is the size of the earth, also the same scale. the sun is large, even compared to the orbit of the moon. the sun is large compared to the entire range of first-hand personal human experience, throughout all of human history. it could easily be contained inside the sun. the sun is 865,000 miles in diameter.

the sun is 109 times the diameter of the earth. from this we can conclude, the sun is big. okay. so with this context now, let me put -- get rid of that stuff and put the sun down in the lower right corner. and bring the orbit of the earth in here. magnify it for a moment to show you that little bluish thing. that's the orbit of the moon. earth its much, much too small to show up in this scale. so, the sun down hire, the orbit of the earth here, the orbit of the moon, dawn was as far away as the sun in 20, is? year four times as far away, more than 1,500 times as far from earth as the moon, well in excess of a million times farther away than the international space station. and that to me is what is really cool.

and corny as it sounds -- i know it sounds corny, on nasa jpr missions i've worked on, including dawn, when the spacecraft has passed on the far side of the sun i've gone outside and put my thumb up and blocked out the sun and thought, gosh, we have a spacecraft on the far side of the sun. this is the same sun that has shown down on our planet for 4-1/2 bill years. the same sun that is the source of virtually all of the energy hour peninsulas has ever had and will ever had. the same sun so dominated human thought and art, literature, culture, philosophy, science, mythology and religion, throughout all of human history. this is the same sun that is the gravitational master of our solar system. the third of a million times the mass of our planet. this is the same sun that is our sign post in the milky way galaxy, and yet we can send spacecraft to the other side of the sun.

when i say we, don't mean the dawn team. don't mean everybody hereby at jpl or anybody at nasa or the entire engineering and science community. mean everybody. think everybody participates in missions like this. to me, everyone who has ever looked up at the night sky in wonder, anyone who has any curiosity at all about earth and how it fits in, anybody who feels that longing to know the cosmos, or who wants to understand the nature of nature, for that matter anybody who just ever felt that drive for a bold adventure, right? a noble undertaking to go beyond the next horizon and see what is there. everybody participates in make like this and that to me it what it most exciting about this kind of thing. because i think dawn and the

other spacecraft around here truly, as human kind's robotic ambassadors to the cosmos, and i think we all share in that, and that's what i think is really rewarding about this. so that raises the question, how do we do this? well, we start by putting the spacecraft on top of a huge bomb and hoping that it blows up in a controlled fashion, and it usually does. and we got dawn off to a beautiful launch. in fact dawn launched at dawn if the sun is rising in background so we left cape canaveral at dawn of 2007 and when we got into space, this is our trajectory and the conventional view with the sun in the center, the orbit of earth, and the orbits of other bodies and we follow the trajectory for dawn along when it's the nice, chameleon blue color and it's

dark is where we are coasting and we launched in september of 2007 when earth was here and you can see we coasted a little bit and then we thrust and had some coasting and thrusting while we were checking out the engines and other systems getting the spacecraft ready for its interplanetary journey. then we got into a preregular pattern of ion thrusting most of the time and just as a subtle technical detail the durations of the coast periods, where we're not thrawing, are exaggerated because the software used to generate this trajectory sample is just once a day. so we're thrusting more than it looks like here. so we have this long coast period during which we flew by mars in order to speed up the spacecraft, and then be continue spiraling gradually farther and farther and farther from the sun, until july of 2011 when we got vesta, went into or bit

around vesta, and maneuvering from one orbit to another around vesta, one of the benefits of the ion propulsion system. we get into or bit and once we're there we can fly to different orbits in order to optimize our describe text investigations. the we use the ion propulsion to break out of vesta orbit and then we got the series went into orbit and the spacecraft will stay there forever, and in fact, where this -- the line turns from bold to light, represents the end of dawn's prime mission, which was june 30th. so we successfully completed the 8.8 year, 3-1/2 billion mile journey just a couple weeks ago but we are very grateful that nasa decided to extend the mission because it's going well

and there are still neat things we do a series so we are continuing our exploration there. so we can zoom in right now and see where dawn is today. we have progressed a little bit beyond the end of the primary mission, and on this scale you can't see the difference between where dawn is and where series are. they're basically in the same place on the scale of the solar system and can zoom in and see where vesta is today. one thing that is interesting is we departed vesta from here, a little more than one vesta year ago and actually dawn is now farther from vesta than the earth is from the sun. again to me this is cool. this is a reminder that this is an interplanetary spaceship. we good to distant bodies. we orbit them and then can travel from there huge distances to go elsewhere to explore as well. so since i mentioned earth we can zoom in and see where earth is today and that's actually writ is right now, and in fact

those who came here, drove in through the guard facility here, went in here, parked up here, and we're in here right now, and actually unfortunately i can see that gentleman back there, you left your lights on, but you might want to go back and take care of that. so that's the overview of the trajectory, but when you look at a picture like this, it's flat and it's static. and it's easy to forget that the solar system is in motion. the way i think of it is the solar system has a big, beautiful complex choreography, and let's look at an an make of what -- animation of what is going on here so get oriented here so you can follow the animation. 0 so the standard view, the sunnies the center. blue is the orbit of earth here. red is the orbit of mars. this is the orbit of vesta and this is the orbit of series, and starting out by showing you the location of these things, where

they were in march of 2007, so you can sort of synchronize your watching of it in preparation for the september 2007 launch. and what you'll see is vesta will go all the way around the sun before we get to and it series goes around almost two full times. it's more complicated than just going out to a certain distance from the sun. you have to ghetto right place at the right time. so here in september 2007 the spacecraft leaves earth, we're now aiming to fly by mars. remember that occurred while we were coasting. so here we have flown by mars, turn on the ion propulsion system. we're aiming for vesta but won't get there until here, and series will go all the way around the sun for another full revolution before we get there. but finally as we get into 2011, dawn gets to vesta, goes into orbit around it, spends 14 months there, making its extensive measurement in

september of 2012, fires up the ion engine heading for series. not that far away but that's a long, arduous climb through the asteroid belt two and a half years to get there, but as we get into early 2015 it did indeed go into orbit and that where the pace spacecraft is right now and will be effectively forever orbiting the sun with the largest body between mars and junior at the. and it's continue -- jupiter, and it's continuing its explore asia of this strange, alien world. so, that's a broad overview of the mission. i can tell you that we have lots offing thes going on woulder very busy, all kinds of things going on all the time. i'm not going to bore you with every imaginable detail of what is happening. instead i will just thank you very much for your attention. i appreciate your letting me tell you about the dawn mission. so, thank you very much. [applause]

>> i'm happy to take questions and please come up to themake crow phone and if you're interested in the dawn mission, you can go to our web site, dawn.jpl.nasa.gov. release a new picture every work day, a new picture of series, we have lots of educational activities there for students and teachers, and of course we're all students, so to there are a lot of neat things to learn if if you enjoy the way i talked about it have a blog there called the dawn journal and write about the mission in the same way i talk about it here and we have more frequent status reports and other things. so, questions. >> yes, thank you very much. the lecture was fascinating.

>> thank you. >> you spoke about the formation of jupiter and how that stopped the formation of these proto planets, and i was wondering of you say more about how that happened. >> sure. so first can somebody verify the microphone worked? i won't repeat the question for you. when jupiter formed, it did several things. one of them is that its gravity tugged and pulled on all this other material that was orbiting the sun, and sort of stirred it up, and the consequence of that is when things hit, they wouldn't necessarily come together with these gentle approaches like this and stick together. rather that, i would tend to hit at higher veils and break apart. it actually ejected a lot of

that material from tom region, that is, scattered it to elsewhere in solar system, and so not only were collisions that occurred less effective in building larger bodies but there were many fewer collisions. much less material to work with. and so what was there didn't get the opportunity to continue growing. did that ant your -- answer your question. >> a fascinating presentation. thank you. >> thank you. >> so you stated one of the main mission points was to measure the gravitational field. what tolerance there is between the gravitational field when the mission starts and when you arrive. how do you account for fluctuations in fuel consumption you how do we account for the fact we didn't know the gravitational field? >> yes. >> it's another one of the many unique aspects of the dawn mission, is this is the only mission ever that has gone to a massive solar system body to orbit it which had not

previously been visited bay fly-buy space forecast. so mercury, venus, mars, jupiter, saturn, all have been visited by fly-by spacecraft so we hat measurements. dawn did not. so there were a number of ways that we accounted for it, but thanks to the flexibility of the ion propulsion system, essentially what we would do is, here's our massive body, here's the spacecraft night in. we would fly toward it, and measure the gravitational pull, if you will, as we got in, determine with the extraordinary and exquisite accuracy, measure the pull and then update our flight plan, our thrust profile, the aiming of the ion engine and the throttle level we.

>> update it to account for our improving accuracy in the gravitational field as we got closer and closer. so, essentially you fly in a little, measure the gravity field. fly in little closer, measure more accurately. fly in still closer and measure it still more accurately. does that make sense? >> thanks. >> yes, sir. >> hello, and congratulations on this extraordinary accomplishment. >> thank you. >> i was wondering as i was looking at the amazing photographs of series, that, wow, it's the surface of series is like a record of every piece of whatever from space that's slammed into it. and i was just wondering, is there -- do you think any of the surface of an object like series this result of any kind of internal forces and there is any way to know that? >> so, that's a good question.

and i give wordy answers. ry'll start with the short answer, yes, there is good reason to believe -- in fact excellent reason to believe that there are internal geological processes. i showed you a crater and you can see it rotating into view in this picture. it will be the bright thing. but as i said, that's the measured to be only 80 million years old. and the bright material there has to be even younger than that. and so there are current geological processes but more to the point you started with the reasonable comment that it's recorded everything that has hit it throughout the almost -- more than 4-1/2 billion year of the

solar system. in fact there are number of areas on series which actually are relatively smooth. that is, don't show many craters. and we have mathematical methods -- i could describe if you're interested -- for predicting how many crate years of certain sizes should occur on series, partly it's based on the crater wed see on vesta, and there aren't as many large killers there as it seems there should be. and so that is the suggestion that perhaps there are geological processes that over time erase those craters, and so one of the things that plan are plan tear geologists are work on now is understanding the nature of the processes. there are other geological evidence as well of the effect

of series internal activity, much more recently, than the -- occurring much more recently than the 4-1/2 billion years since it form. does that make sense? >> yes. thank you. >> you're welcome. >> good evening. just two questions on the design of the spacecraft. first of all you mentioned it had another ion engine which i assume is two. >> we have three. >> you have throw. >> -- the "star wars" fight are is three. our lasers aren't as powerful as theirs but can't have everything. >> theirs where gold plated. it was a military project. >> that's right. >> is that strictly for redundancy or actually use those to eliminate the need to turn the craft around? >> okay. so that's a good question. before i answer let me explain. when he asked about redundancy,

do we have more than one in case one fails. that's what you mean. >> yes. >> so, it turns out that there's a mechanism that we understand very well by which ion engines wear out in space because of use. just like -- lots of physical devices get consumed by their use, and so given the amount of propellent we had to expend in order to accomplish the dawn mission we had to have two ion engineses, that its, one would wear out too soon or didn't have sufficient confidence we could do it with one. so we carried two in order to have sufficient lifetime, and then the third is for exactly what you raised. so that was an incorrectful observation, the third is in case one fails. however, all three are still healthy, so we didn't have any problems with the ion engine,

and we don't pick them on the basis of what direction we want to thrust because you can even see in this picture -- i'm going to turn this picture off in a moment only because my computer doesn't like staying on one picture for too long, but -- maybe it will quit for me and embarrass it owl when it says power point has a problem. but there's onen inhere, one here, and one on the back side. so that not enough to cover all the directions anyway. if you want to point an engine in this way. so we don't use it for that purpose. if we want to point an engine in that direction we rotate the entire spacecraft and point the engine in that direction and go there. >> thank you. seems to be -- this is an ambitious side of a solar array to have work and unfold perfectly and everything. did you have a tradeoff between thinking of using a radio isotope power supply? i thank you for the answer. >> might want to wait until after i've answered it but that

your call. once again for other people's benefits this radio isotope thing he render to is -- in fact you can see them for the people in the room -- you can't see the hisser pointer but this black structure sticking out of the side of voyager here, is what is called a rideow isotope thermoelectric generator, the scale mod of the cassini spacecraft has them here. you can see models on the galileo spacecraft as well. so, these are devices which contain radio active materials, which when they decay produce heat, and that heat is used to produce electricity. and it's not a nuclear reactor but uses nuclear energy. and we do not consider using them on dawn for several reasons. one is they are very, very expensive. and so you only use them if you really have to.

they were well worth the investment for the fabulous return of voyager and cassini here and galileo and other missions, many other missions. but also they actually don't produce enough electrical power. devices like that only can produce 100 or few hundred wtoth watts and the ion engine itself, just to turn it on, takes well over 500 watts. just to turn it on, and normally -- in fact we have actually never operated it at that low power level. when we started we were thrusting with more than two kill watts did the mass of these devices would completely overwhelm the benefit of the ion propulsion system because we have to propel that mass through the solar system. so having these large solar arrays was the better trade. but every mission makes its own trade on the most effective way

to accomplish whatever its objectives. i lost track of the he gentleman but i hope answered his question. >> thank you so much. was wondering howl we know that asteroid debris on earth came from vesta, and why the north part of it is much more densely cratered than the south. >> okay. so the first part, how do we know that these meteorites -- i forgot to say if you want to take a look at this afterwards you're welcome to. how do we niece came from earth? a number of lines of evidence but it started with a method that i need to explain to you called infrared reflectant spectrum. infrared, wave length oflight that we can't see. but we know is there just as there are wave lengths of sound we can't hear but your dog can confirm for you there are wave lengths of sound we can't hear but are detectable so wave lengths of light we can't see,

infrared. reflectants, the light from the sun bounces off vesta goes elsewhere and the spectrum is where you break up the lite into constituent colors so think of using a prism on white light ask and you see all the color 0 the rain bow. we can do that with infrared light as well and it turns out when you do that, the infrared reflection contains the fingerprint or the signature of the material that reflected it. some infrared wave lengths are reflected very strongly, so it's bright, some are not reflected very well so it's dark. and so this produces a distinctive pattern for different materials. and so in around 1970, astronomers started using infrared detectors to look at

astronomical bodies. they looked at vesta, measured the infrared reflectant spectrum and found it was wonderful match for this large class of minerals that occurred in these meteorites for experts and minerals are -- so the meteorites if you want to get them, they're actually not very expensive because they're so common. bought this myself before i even ever heard of the dawn mission itch thought it would be cool to own apiece of vesta. ... >> the other question you asked

is wise the northern hemisphere more densely created than the southern hemisphere. the reason is because of the impact that excavated this material happened to occur deep in the southern hemisphere is helpful. so some of that material was thrown out with so much energy that it left the vicinity and went elsewhere including two here on earth. some of it just like if you had a big impact here on earth, some other stuff would the stuff would fly up and come down some place else. so it landed elsewhere in the southern hemisphere and it raised the crater that are ready form there, it resurfaced it. so you can think of it as the northern hemisphere recur records for billion years of stuff falling on it where is the southern hemisphere had its record wiped clean so it only requires 1,000,000,000