Astronomy and Cosmology

3685 topics in this forum

1. Astronomy links 1 2 3 4 5

   By Martin, May 24, 2004
   • 105 replies
   • 103.5k views
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   • swansont
   • June 25, 2021

2. Cosmological Principle 1 2 3

   By Mordred, May 30, 2015
   • 52 replies
   • 36k views
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   • michel123456
   • June 22, 2020

3. Cosmo Basics

   By Martin, October 19, 2008
   • 13 replies
   • 27.3k views
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   • swansont
   • August 3, 2018

4. Using BOINC / seti@home?

   By Sayonara, August 29, 2010
   • 10 replies
   • 20.5k views
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   • Altruist1
   • March 26, 2016

5. Where Does Space End? It Must End Somewhere! 1 2 3 4 41

   By Edisonian, October 6, 2004
   • 1k replies
   • 337.7k views
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   • hypervalent_iodine
   • November 24, 2016

6. Gravity waves and the aether 1 2 3 4 32

   By Moontanman, June 16, 2016
   • 779 replies
   • 57.8k views
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   • imatfaal
   • September 6, 2016

7. Is the Universe infinite? 1 2 3 4 16

   By dordle-loddle, August 1, 2017
   • 385 replies
   • 37.9k views
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   • Strange
   • August 14, 2018

8. If there is no end to the space 1 2 3 4 11

   By HamsterPower, January 14, 2011
   • 263 replies
   • 35.4k views
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   • owl
   • March 24, 2011

9. Astronomy word game. 1 2 3 4 10

   By Mad For Science, July 17, 2015
   • 246 replies
   • 16.9k views
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   • ACG52
   • August 7, 2015

10. SpaceX 1 2 3 4 10

    By ThatSpaceBoy, April 16, 2021
    • 230 replies
    • 16.9k views
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    • dimreepr
    • May 12, 2021

11. Space Ends 1 2 3 4 9

    By zazzzoom, March 20, 2005
    • 210 replies
    • 22.9k views
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    • Dave
    • September 30, 2005

12. Can we see it? 1 2 3 4 9

    By michel123456, March 16, 2010
    • 206 replies
    • 24.2k views
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    • Spyman
    • May 6, 2010

13. What dates are accepted for the age of the Sun? 1 2 3 4 8

    By Robittybob1, February 9, 2016
    • 195 replies
    • 13.1k views
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    • hypervalent_iodine
    • February 23, 2016

14. Is the universe at least 136 billion years old, is the universe not expanding at all, did the universe begin its expansion when Hubble measured its redshift for the first time or was light twice as fast 13.5 billion years ago than it is today? 1 2 3 4 8

    By tmdarkmatter, August 7, 2023
    • 187 replies
    • 8k views
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    • swansont
    • November 27, 2023

15. what was there before Big Bang? 1 2 3 4 7

    By nernico, June 30, 2011
    • 166 replies
    • 23.1k views
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    • space noob
    • May 9, 2012

16. State of "matter" of a singularity 1 2 3 4 7

    By gatewood, June 21, 2021
    • 157 replies
    • 11k views
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    • Mitcher
    • October 1, 2022

17. If the universe is expanding, what are we filling up? 1 2 3 4 7

    By Soulja, January 9, 2003
    • 156 replies
    • 16.3k views
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    • JaKiri
    • July 20, 2004

18. How does the Sun get orbital energy to start orbiting a barycenter? 1 2 3 4 7

    By Robittybob1, February 7, 2015
    • 156 replies
    • 13.4k views
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    • Robittybob1
    • February 19, 2015

19. Dead galaxy questions 1 2 3 4 7

    By Bmpbmp1975, February 11, 2020
    • 156 replies
    • 18.2k views
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    • Phi for All
    • February 15, 2020

20. Field Question 1 2 3 4 7

    By MikeAL, May 4, 2018
    • 151 replies
    • 12.4k views
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    • MikeAL
    • May 9, 2018

21. Asteroid 'gives Earth a close shave' on Monday 1 2 3 4 6

    By DrDNA, March 3, 2009
    • 146 replies
    • 16.8k views
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    • dragonstar57
    • August 10, 2010

22. The Beginning of the Universe 1 2 3 4 6

    By Chris Sawatsky, November 12, 2023
    • 145 replies
    • 4k views
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    • Mordred
    • April 5

23. Different responses to Fermi Paradox 1 2 3 4 6

    By Martin, July 21, 2009
    • 142 replies
    • 22.7k views
    • 
    • Widdekind
    • December 23, 2011

24. Suppose that I am looking in my telescope to a distant star 1 2 3 4 6

    By michel123456, November 22, 2014
    • 140 replies
    • 12.5k views
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    • Ophiolite
    • December 20, 2014

25. first contact 1 2 3 4 6

    By MRlogic, September 22, 2010
    • 132 replies
    • 17.9k views
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    • Airbrush
    • November 21, 2010