Astronomy and Cosmology

3689 topics in this forum

1. How does General Relativity predict zero volume/infinite density of Black holes?

   By Nigel Denning, May 28, 2021
   • 2 replies
   • 768 views
   • 
   • swansont
   • May 28, 2021

2. Dark matter mystery.

   By AlexandrKushnirtshuk, May 27, 2021
   • 3 replies
   • 828 views
   • 
   • Phi for All
   • May 27, 2021

3. Earth The Size Of A Tennis Ball

   By Photon Guy, March 1, 2021
   • 3 replies
   • 1.1k views
   • 
   • iNow
   • May 21, 2021

4. Space - Can Private Industry actually compete with China?

   By DeepSeaBase, May 11, 2021
   • 14 replies
   • 1.6k views
   • 
   • SpaceJac111
   • May 21, 2021

5. Space Travel - is it leisurely possible? (Can we tolerate risk?)

   By DeepSeaBase, May 11, 2021
   • 6 replies
   • 1.1k views
   • 
   • beecee
   • May 20, 2021

6. Get ready for the landing of Perseverance ! 1 2

   By Airbrush, February 11, 2021
   • 35 replies
   • 3.9k views
   • 
   • SpaceJac111
   • May 20, 2021

7. The universe is flat? (split from Time for a different view)

   By MPMin, May 18, 2021
   • 19 replies
   • 1.6k views
   • 
   • studiot
   • May 20, 2021

8. Correspondence between mass/radius of both the observable universe and black holes

   By MarkE, May 12, 2021
   • 9 replies
   • 1k views
   • 
   • joigus
   • May 18, 2021

9. SpaceX 1 2 3 4 10

   By ThatSpaceBoy, April 16, 2021
   • 230 replies
   • 17.3k views
   • 
   • dimreepr
   • May 12, 2021

10. There may be 14 antimatter objects hiding in the Milky Way. These objects are called anti-stars.

    By SergUpstart, May 4, 2021
    • 8 replies
    • 1.3k views
    • 
    • swansont
    • May 5, 2021

11. Dark Matter and Suspiciously Warm Planets:

    By beecee, May 4, 2021
    • 1 reply
    • 688 views
    • 
    • beecee
    • May 5, 2021

12. False picture possible on optical telescopes

    By Yanosh, May 4, 2021
    • 3 replies
    • 777 views
    • 
    • beecee
    • May 4, 2021

13. New exoplanet candidate found in the habitable zone of the closest star system

    By USer2343, February 28, 2021
    • 7 replies
    • 1.3k views
    • 
    • beecee
    • May 3, 2021

14. Russias submarine launched satellite

    By IDNeon, May 3, 2021
    • 2 replies
    • 714 views
    • 
    • Phi for All
    • May 3, 2021

15. April 12th: 1961.

    By beecee, April 9, 2021
    • 21 replies
    • 1.7k views
    • 
    • beecee
    • May 3, 2021

16. Paradox of visual and actual positions in space.

    By AlexandrKushnirtshuk, April 13, 2021
    • 8 replies
    • 1.1k views
    • 
    • IDNeon
    • May 3, 2021

17. Could you use Carbon Nanotube Yarn/Twistron Yarn and a black hole to theoretically create a Infinite Energy Source?

    By Liliander, April 27, 2021
    • 1 reply
    • 585 views
    • 
    • swansont
    • April 27, 2021

18. Crashing into Andromeda 1 2

    By wildie9, February 10, 2021
    • 41 replies
    • 5.8k views
    • 
    • cannongray
    • April 27, 2021

19. Hill sphere shape

    By Zura, April 20, 2021
    • 7 replies
    • 1k views
    • 
    • Zura
    • April 20, 2021

20. First I heard of this! [Gotta have a giggle]

    By beecee, April 13, 2021
    • 1 reply
    • 655 views
    • 
    • beecee
    • April 13, 2021

21. Life Near a Red Dwarf Star

    By Airbrush, March 31, 2021
    • 11 replies
    • 1.8k views
    • 
    • Airbrush
    • April 13, 2021

22. Researchers confirm accuracy of cosmological data analysis technique:

    By beecee, March 19, 2021
    • 0 replies
    • 642 views
    • 
    • beecee
    • March 19, 2021

23. Does the expansion of space mean anything for the movement of matter in space?

    By Alex Mercer, March 18, 2021
    • 18 replies
    • 1.5k views
    • 
    • Prof Reza Sanaye
    • March 19, 2021

24. The expanding universe

    By geordief, March 18, 2021
    • 6 replies
    • 935 views
    • 
    • MigL
    • March 19, 2021

25. Recommend a textbook

    By Toby Jug, March 2, 2021
    • 5 replies
    • 861 views
    • 
    • Toby Jug
    • March 2, 2021