they held that the sun and planets condensed from a nebula. support for this idea came with development of more powerful telescopes and spectrometers, which can detect the composition of material deep in space. nebula are created by the explosion of stars which have exhausted their nuclear fuel. by studying the compositions of nebula, astronomers have found evidence that stars and planets can form from these interstellar clouds. 99% of nebular material is composed of hydrogen and helium gas. but about 1% consists of tiny bits of solid matter-- silicon compounds, iron oxides, carbon, and a host of other materials, all of which are found in the sun and planets. if the force of gravity between the gas and bits of cosmic dust is strong enough, this matter is gradually pulled together. as the nebula contracts, it starts spinning, with heat setting its particles in motion. the further it condenses, the faster it rotates. the process is something like what happens when a skater condenses himself by drawing in his arms until his body becomes a blur. g

the sky is dark enough that a rich variety of star clusters, nebulas, and galaxies are visible with small telescopes and binoculars or even with the unaided eye. one can even see the milky way are to across the sky. a few places in the inner bay area provide such views of the cosmos. the dark sky is a wonderful educational and aesthetic resource that deserves to be protected for all san francisco's people. hobbyist astronomers, families with kids, and ordinary folks eager to connect with the larger universe. our local astronomical community has long gone public outrage at lands and while sutra heights park provides a spectacular view of the coastline. the 150,000 watts of stadium lighting on until 10:00 p.m. each night include in the proposed beach shelle complex will likely seriously degrade this precious civic research. due to the amount of for scattered light, a large area of artificial sky glowed would dominate wide use near the context -- in the area. regardless of how well the fixtures themselves could be shielded, a huge amount of light reflected on to the surfaces. based on 150 pf

it is the ideal place to observe the southern cross and nebula, only visible in the southern hemisphere. >> ozawa works as a tour guide to the stars. ozawa became enchanted with the village 20 years ago. so enchanted, he moved here from japan. the tour bus brings to the mountain top. from this spot, a hidden universe comes alive pt. the fillingy way stretches across the heavens. >>> that kind of reaction is making the tourist popular. but ozawa is worried about the future of star gazing. his big fear is light pollution. the village has grown, meaning more lights from households and commercial buildings. >> how can the natural beauty be preserved? ozawa came up with the deal of applying for the world heritage listing. international recognition will make residents proud of their natural treasure and encourage them to protect it. >> star conservation took hold, the idea of the world heritage listing has grown support. in this house, the residents use as little light as possible. >> that is the most important thing is to make sure that light doesn't reflect into the sky. that's quite smbl f

a good many arguments against the nebulae sion of rates and i have but the library scandal it seems to me is is this as a scandal is almost infinitely insignificant the significant scandal is that is the ongoing been a collection of rates by our central banks why do you think more people are making that connection hey of course so upset about live our lives why aren't we more upset about central bank menefee elation at rates as a realist i think that i think there is a ritual loathing of of big money and big financial institutions that is certainly understandable and not entirely misplaced because these outfits are kind of state sponsored cartels in good measure you know they. know. not many of them would be standing upright and solvent except for the intercession of the central banks. better now that i think of it just celebrating its two hundredth birthday. is only two hundred years old thanks to the taxpayers yeah yeah afterwards they said even though it's anybody else be worth it to us yeah yeah so it's it's not as if people should feel. some throbbing resentment against these mega

the pink blotches are regions where stars are currently forming, as in the orion nebula in our own galaxyand the rest of the arms are blue because they're full of young stars that are extremely hot and blue. the central bulge, by contrast, is full of much older, yellower stars. most of the stars that are currently lighting up the arms will burn out in fairly short order, within 100 million years or so. meanwhile, new stars will be born in the dust clouds on the adg gef e ir as, so pretty soon, in cosmic terms, the areas that are now bright will look dark, and vice versa. so spiral arms aren't permanent structures; they're actually waves of star formation that move through galaxies independent of the stars inside them. it's much like watching waves on a lake. the waveco taryo b the water itself stays put. next week, we'll talk about two tiny but very attractive coteatnsdehis d sagitta. until then, this is tony flanders from sky & telescope magazine, wishing you clear skies and great views. brought to you by: captionebyin21