Astronomy and Cosmology

3713 topics in this forum

1. Cosmological redshift, another thought experiment

   By Genady, January 20, 2022
   • 4 replies
   • 737 views
   • 
   • Genady
   • January 20, 2022

2. We and cosmic scales

   By Genady, January 18, 2022
   • 6 replies
   • 1k views
   • 
   • iNow
   • January 19, 2022

3. Jobs

   By EdenFechter, January 18, 2022
   • 0 replies
   • 680 views
   • 
   • EdenFechter
   • January 18, 2022

4. Cosmological redshift, thought experiment

   By Genady, January 16, 2022
   • 18 replies
   • 1.5k views
   • 
   • MigL
   • January 18, 2022

5. Is it easy to shade the Earth for cooling? 1 2

   By Kevin_Hall, January 6, 2022
   • 26 replies
   • 2.6k views
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   • mistermack
   • January 8, 2022

6. Start of time ?

   By Genady, January 4, 2022
   • 9 replies
   • 960 views
   • 
   • Markus Hanke
   • January 6, 2022

7. Rocket fuel

   By Kevin_Hall, January 4, 2022
   • 8 replies
   • 1.1k views
   • 
   • Ken Fabian
   • January 6, 2022

8. What is the mechanism for SPACE EXPANSION ?

   By Marius, January 2, 2022
   • 15 replies
   • 1.9k views
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   • Phi for All
   • January 5, 2022

9. Does space have mass ? If not, how does it accelerate ?

   By Marius, January 4, 2022
   • 20 replies
   • 1.7k views
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   • swansont
   • January 5, 2022

10. "Our space is curved" 1 2

    By Genady, January 2, 2022
    • 33 replies
    • 3.7k views
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    • Genady
    • January 3, 2022

11. The Universe's First Molecule Found:

    By beecee, January 3, 2022
    • 4 replies
    • 917 views
    • 
    • exchemist
    • January 3, 2022

12. What is the mechanism for the BIG BANG ?

    By Marius, January 3, 2022
    • 13 replies
    • 1k views
    • 
    • Ghideon
    • January 3, 2022

13. Happy New Year, astronauts!

    By Kevin_Hall, December 31, 2021
    • 0 replies
    • 586 views
    • 
    • Kevin_Hall
    • December 31, 2021

14. Dark Matter:

    By beecee, December 18, 2021
    • 6 replies
    • 1.3k views
    • 
    • MigL
    • December 23, 2021

15. Could the real size of the universe be infinite? 1 2 3

    By Strange Me, July 7, 2021
    • 71 replies
    • 7.9k views
    • 
    • skydelph
    • December 8, 2021

16. Do black holes have a centre?

    By geordief, December 2, 2021
    • 22 replies
    • 1.7k views
    • 
    • MigL
    • December 8, 2021

17. Naturally occurring elements heavier than U ?

    By Airbrush, November 12, 2021
    • 6 replies
    • 1.8k views
    • 
    • skydelph
    • December 3, 2021

18. If the sun were to go red giant wouldn't it cause all planets to move as well?

    By inbreeding, September 14, 2021
    • 9 replies
    • 1.7k views
    • 
    • Kevin_Hall
    • December 3, 2021

19. Atmosphere of Venus (split from An absolutely bonkers plan to give Mars an artificial magnetosphere)

    By Bufofrog, November 22, 2021
    • 6 replies
    • 857 views
    • 
    • swansont
    • November 23, 2021

20. Gravity wells determine orbital plane? 1 2

    By DeckerdSmeckerd, November 18, 2021
    • 35 replies
    • 3.3k views
    • 
    • Ghideon
    • November 22, 2021

21. Alone again?

    By geordief, November 21, 2021
    • 8 replies
    • 1.1k views
    • 
    • geordief
    • November 22, 2021

22. Oumuamua - mathematical question

    By DeckerdSmeckerd, November 14, 2021
    • 22 replies
    • 2k views
    • 
    • DeckerdSmeckerd
    • November 16, 2021

23. Some (Interested Layman's) "What if?"-Questions Regarding Neutron Stars

    By Godot, November 10, 2021
    • 10 replies
    • 1.2k views
    • 
    • beecee
    • November 13, 2021

24. What is correct calculation for Moon's brightness?

    By Jurassic Park, August 23, 2021
    • 5 replies
    • 2.9k views
    • 
    • Solon
    • November 12, 2021

25. Augmented Solar Sail. Would this work?

    By mistermack, October 31, 2021
    • 12 replies
    • 1.7k views
    • 
    • mistermack
    • November 8, 2021