Martin Posted March 11, 2006 Author Posted March 11, 2006 http://arxiv.org/abs/astro-ph/0601168 best estimates of things like the hubble parameter, dark energy density, baryon matter density, dark matter, and so on new WMAP data might be coming out this month that could cause some of these numbers to be revised, but this is a clear concise summary of the current estimates with some intersecting bubble diagrams that communicate some of how they are arrived at
Martin Posted March 19, 2006 Author Posted March 19, 2006 the WMAP data did come out this Thursday here is one of the papers Spergel et al Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology http://lambda.gsfc.nasa.gov/product/map/dr2/pub_papers/threeyear/parameters/wmap_3yr_param.pdf
softdragonz Posted April 14, 2006 Posted April 14, 2006 Hi SFN... There is this new website I made for astronomers and space enthusiasts.... the link is.... http://www.vit.ac.in/seds_vit/default.html It has a full fledged discussion forum ..... a space article database..... among many others
mooeypoo Posted May 21, 2006 Posted May 21, 2006 Great place to watch an explanation about String Theory and the expanding universe: http://www.pbs.org/wgbh/nova/elegant/program.html ~moo
S.Ingvar Posted June 19, 2006 Posted June 19, 2006 this thread can be for stashing links to webpages with good explanations of astronomy stuff.Join in if you feel like it. On this webpage you can find many "good explanations of astronomy stuff" as well as new insights about the whole physics. http://www.theuniphysics.info Ingvar, Sweden
Martin Posted June 30, 2006 Author Posted June 30, 2006 Interactive black hole feature at Hubblesite http://hubblesite.org/discoveries/black_holes/home.html Several SFN people liked this. Discussion here: http://www.scienceforums.net/forums/showthread.php?t=21714
Martin Posted September 22, 2006 Author Posted September 22, 2006 we have been using Ned Wright's cosmology calculator here at SFN for over two years now. it was one of the first things I posted about at beginning of this thread. here is a writeup about the calculator http://arxiv.org/abs/astro-ph/0609593 A Cosmology Calculator for the World Wide Web Edward L. Wright (UCLA) 8 pages with 1 included figure. Cosmology calculator available at this http URL, light travel time converter at this http URL and the advanced cosmology calculator at this http URL "A cosmology calculator that computes times and distances as a function of redshift for user-defined cosmological parameters is available on the World Wide Web. This note gives the formulae used by the cosmology calculator and discusses some of its implementation. A version of the calculator that allows one to specify the equation of state parameter w and w' and neutrino masses, and a version for converting the light travel times usually given in the popular press into redshifts are also available."
Jacques Posted November 17, 2006 Posted November 17, 2006 It may interest some of you : On Sunday, Nov. 19th, Earth will pass through a stream of debris from comet 55P/Tempel-Tuttle. The result: a shower of Leonid meteors. "We expect an outburst of more than 100 Leonids per hour," says Bill Cooke, the head of NASA's Meteoroid Environment Office in Huntsville, AL. http://science.nasa.gov/headlines/y2006/14nov_leonids.htm
Martin Posted May 26, 2007 Author Posted May 26, 2007 http://www.uni.edu/morgans/ajjar/Cosmology/cosmos.html
Fred56 Posted October 16, 2007 Posted October 16, 2007 Found a pretty nice EMR chart (nowhere else to put it): http://www.lot-oriel.com/site/site_down/cc_light_deen01.pdf Just for good measure, what a Mr Fradkin thinks we should be looking for: http://online.kitp.ucsb.edu/online/qubit_c06/fradkin/pdf/Fradkin1_KITP.pdf
Martin Posted January 17, 2008 Author Posted January 17, 2008 Updating some basic cosmology links: Ned Wright's cosmology tutorial http://www.astro.ucla.edu/~wright/cosmolog.htm Ned Wright's cosmology FAQ http://www.astro.ucla.edu/~wright/cosmology_faq.html Ned Wright's most basic cosmology calculator http://www.astro.ucla.edu/~wright/CosmoCalc.html (he has links to some more advanced or specialized calculators) Morgan's calculator http://www.uni.edu/morgans/ajjar/Cosmology/cosmos.html Murphy's coordinate conversion tool http://fuse.pha.jhu.edu/support/tools/eqtogal.html Lineweaver and Davis' Scientific American article Misconceptions about the big bang March 2005. AS LONG AS THIS PRINCETON LINK WORKS IT IS BETTER THAN THE OTHERS http://www.astro.princeton.edu/~aes/AST105/Readings/misconceptionsBigBang.pdf Here are the links to the same article at the SciAm website. But these links have been going dead or else the GRAPHICS that you used to get have been disappearing. So these SciAm links may not be as good as the Princeton one http://www.sciam.com/article.cfm?chanID=sa006&colID=1&articleID=0009F0CA-C523-1213-852383414B7F0147 The Lineweaver Davis article had some very useful SIDEBARS giving pictorial diagrams with a question together with right and wrong answers explained. For easier access, here are links to individual sidebars. http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p39.gif What kind of explosion was the big bang? http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p40.gif Can galaxies recede faster than light? http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p42.gif Can we see galaxies receding faster than light? http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p43.gif Why is there a cosmic redshift? http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p44.gif How large is the observable universe? http://www.sciam.com/media/inline/0009F0CA-C523-1213-852383414B7F0147_p45.gif Do objects inside the universe expand, too?
Martin Posted September 2, 2008 Author Posted September 2, 2008 Some recent cosmology data and estimates: Komatsu et al (WMAP 5th year data, cosmology implications) http://arxiv.org/abs/0803.0547 They publish a lowerbound estimate for the radius of curvature of the universe--95 percent confidence level. See Figure 2 on page 4 and convert the units to lightyears ( 23 *(1/0.72)*3.26 billion lightyears = 104 billion lightyears ) A 'best fit' estimate derived from Ned Wright's January paper was 130 billion lightyears, not far from their lower bound. So space might have infinite volume but it also might very well have finite. And if it has finite volume then they are telling us the length of the longest possible straight line is AT LEAST 2 pi times 104 billion lightyears-----in other words about 650 billion LY. That's the idea of giving a lower bound. The circumference has to be at least 650 billion LY. It could be more, and it could be infinite, but with 95% confidence it cannot be less. If you could travel at a billion times c, then you could start out from earth and travel in the straightest possible line for at least 650 years before getting back to square one.
Martin Posted June 1, 2009 Author Posted June 1, 2009 Nobel laureate George Smoot on observational cosmology, early universe, microwave background... General audience, charts, graphs, but no equations. http://www.revver.com/video/827006/the-history-and-fate-of-the-universe-part-1-of-9/ http://www.revver.com/video/827106/the-history-and-fate-of-the-universe-part-2-of-9/ http://www.revver.com/video/827171/the-history-and-fate-of-the-universe-part-3-of-9/ http://www.revver.com/video/832550/the-history-and-fate-of-the-universe-part-4-of-9/ http://www.revver.com/video/832599/the-history-and-fate-of-the-universe-part-5-of-9/ http://www.revver.com/video/832643/the-history-and-fate-of-the-universe-part-6-of-9/ http://www.revver.com/video/832679/the-history-and-fate-of-the-universe-part-7-of-9/ http://www.revver.com/video/832724/the-history-and-fate-of-the-universe-part-8-of-9/ http://www.revver.com/video/832788/the-history-and-fate-of-the-universe-part-9-of-9/
ExploreScience Posted February 5, 2011 Posted February 5, 2011 What a great list of resources. I have been putting together a list of books, magazines, and news sources for people interested in astronomy and other fields in science and technology. The site is Explore-Science.net. Great Astronomy Books is a growing list of the best reads in astronomy. The Astronomy Magazines page presents the top picks for astronomy articles. Finally, the Astronomy News section gathers the best sources on the web for astronomy discoveries and research.
Klaynos Posted November 10, 2011 Posted November 10, 2011 ! Moderator Note Summerwind's post about a new idea has been split and moved to speculations http://www.scienceforums.net/topic/61312-summerwinds-no-dark-energy-proposal/
the asinine cretin Posted June 4, 2012 Posted June 4, 2012 This is pretty awesome. 258 Astronomy Lectures from UC Berkeley
maminsin21 Posted July 6, 2012 Posted July 6, 2012 DOWNLOAD NATIONAL GEOGRAPHIC MAGAZINES FOR FREE!!! http://adf.ly/AQ0K5
Coty Posted July 16, 2012 Posted July 16, 2012 This is the sire were are needed specialists for Ecyclopedia about creation of the world http://postanaksveta.blogspot.com/p/big-encyclopedia-of-world.html Also has English & Serbian version, visit and enjoy!
Paal Brekke Posted July 19, 2012 Posted July 19, 2012 Now since the Sun is very active and Space Weather is a hot topic. You may find this book interesting..comes with online multimedia material. http://www.springer.com/astronomy/extraterrestrial+physics%2C+space+sciences/book/978-1-4614-0570-2?changeHeader http://www.amazon.com/Our-Explosive-Sun-Visual-Source/dp/146140570X/ref=sr_1_1_title_0_main?s=books&ie=UTF8&qid=1312879357&sr=1-1 Cheers Pål ----------
Akram Fakir Posted October 6, 2012 Posted October 6, 2012 A lot of discussions I see. Thank you all the discussions. I will be back to you. Today I am not going to discuss something as this is my first day in the community. I want to visit on the forum and give you thank for the nice posts.
proximity1 Posted March 13, 2013 Posted March 13, 2013 Prof. Christopher Martin's "Space Astrophysics Laboratory", associated with Cal Tech. wtih, among its interesting links, this one: "GALEX", the Galaxy Evolution Explorer.
krash661 Posted April 19, 2013 Posted April 19, 2013 some might find this interesting or useful, http://workshop.chromeexperiments.com/stars/ " If you're running on Chrome browser, check out Google's latest Experiment project - it visualizes the precise location of at least 100,000 stars in our Milky Way galaxy, using various imagery and data pulled from NASA and the European Space Agency (ESA). For your frame of reference, there are approximately 200 to 400 billion stars in the Milky Way galaxy. " zoom in all the way to see the sun,zoom all the way out to see the galaxy. or everything in between. you can grab this with your mouse and move any axis's plane. take the tour that's provided.
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