Astronomy, Astrophysics, Cosmology Forum

Join in expert discussion on the topics of Astronomy, astrophysics and cosmology. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.

Threads

High School What is difference between platenary core, mantle & crust?

  • swampwiz
  • · Replies 5 ·
Replies
5

Undergrad Can anyone help with this satellite question?

  • Sokos90
  • · Replies 4 ·
Replies
4

High School We have kittens in orbit around Saturn

  • Noisy Rhysling
  • · Replies 3 ·
Replies
3

High School Where Can I Find the RA and Dec of the V1 Star?

  • Curious Kid
  • · Replies 6 ·
Replies
6

High School Black holes in the centres of galaxies

  • davidge
  • · Replies 27 ·
Replies
27

Cassini's Grand Finale - Fascinating New Insight

  • Stavros Kiri
  • · Replies 49 ·
2
Replies
49

Stargazing How Does Gravitational Lensing Work?

  • Soundariya Raja
  • · Replies 13 ·
Replies
13

High School What are the mystery lights in the sky and how can you identify them?

  • jedishrfu
  • · Replies 4 ·
Replies
4

High School Does the Singularity Really Exist Beyond the Standard Model?

  • wolram
  • · Replies 6 ·
Replies
6

High School A terrestrial, temperate planet around Proxima Centauri

  • Ygggdrasil
  • · Replies 60 ·
3
Replies
60

Undergrad What spatial scales does dark matter become significant?

  • Albertgauss
  • · Replies 3 ·
Replies
3

High School Is there a way to prove that men have gone to the moon

  • Tio Barnabe
  • · Replies 23 ·
Replies
23

High School Understanding Black Body Radiation and the Sun's Color Temperature

  • riz
  • · Replies 2 ·
Replies
2

Stargazing Stunning 2017 Eclipse Photos of the Corona Chromosphere

  • Chronos
  • · Replies 68 ·
3
Replies
68

High School The Most Primitive Star-Forming Galaxy Ever Found

  • CygnusX-1
  • · Replies 2 ·
Replies
2

Undergrad Expanding universe and quantum wavefunctions

  • durant35
  • · Replies 11 ·
Replies
11

Stargazing Child-like pleasure in seeing ISS and detached Dragon capsule

  • UsableThought
  • · Replies 7 ·
Replies
7

High School Could we shade the Earth from the Sun to save Earth?

  • Bmaxwell
  • · Replies 26 ·
Replies
26

Undergrad Did Phase Transitions Drive Inflation in the Early Universe?

  • Vrbic
  • · Replies 9 ·
Replies
9

Undergrad T-symmetry and WDWE with regards to a Universe from Nothing

  • zeroace
  • · Replies 7 ·
Replies
7

High School How does the earth's magnetic field stop radiation?

  • Lunct
  • · Replies 24 ·
Replies
24

Undergrad What is the best source for COBE/WMAP/PLANCK mission data on the early universe?

  • RJLiberator
  • · Replies 2 ·
Replies
2

High School Miscellaneous Trivia: Planets and Moons

  • Shawn Landau
  • · Replies 7 ·
Replies
7

Graduate Galaxy dynamics explained without DM or MOND

  • Adrian59
  • · Replies 1 ·
Replies
1

High School Can Optical Interferometers Extend Beyond 1 Light Second in Length?

  • smartalek86
  • · Replies 1 ·
Replies
1

Graduate Press Schechter function -- the variance on mass scale

  • classy cal
  • · Replies 1 ·
Replies
1

High School Collision of Stars: How Often & How Many?

  • davidge
  • · Replies 14 ·
Replies
14

High School What do you think of the new names for features on Pluto

  • wolram
  • · Replies 2 ·
Replies
2

Stargazing Worth it to buy 2" eyepieces for Newtonian telescope?

  • lomidrevo
  • · Replies 27 ·
Replies
27

High School Pale Blue Dot Project: Img. Earth-Like Planet w/ 18" Mirror?

  • kolleamm
  • · Replies 6 ·
Replies
6

Stargazing Yet another Wall Street Journal article about space debris

  • UsableThought
  • · Replies 1 ·
Replies
1

Undergrad Questions about planetary magnetic fields

  • Hawksteinman
  • · Replies 11 ·
Replies
11

Undergrad Event Horizon and the Mass of a Black Hole

  • Arman777
  • · Replies 12 ·
Replies
12

Undergrad What causes pressure in White Dwarfs and Neutron Stars?

  • Ethan Singer
  • · Replies 4 ·
Replies
4

Graduate Is the Parenago Discontinuity a real thing?

  • DrBwts
  • · Replies 7 ·
Replies
7

Undergrad Safe distance from a neutron star

  • Blue Shift 2112
  • · Replies 4 ·
Replies
4

Undergrad Meaning of permeability in free space

  • TheCanadian
  • · Replies 10 ·
Replies
10

Undergrad Dark matter/energy, why must it be there?

  • Pedro Batista
  • · Replies 30 ·
2
Replies
30

Undergrad Is the speed of gravitational waves non- dispersive?

  • shadishacker
  • · Replies 1 ·
Replies
1

Undergrad Why are the planets revolving around their own axis?

  • Neolight
  • · Replies 21 ·
Replies
21

High School Does gravity self interact with itself

  • wolram
  • · Replies 7 ·
Replies
7

Undergrad Rainbows on Tatooine: A Binary Star System Mystery

  • stefan r
  • · Replies 1 ·
Replies
1

High School Does this paper disprove the possibility of a new universe creation?

  • Yid
  • · Replies 3 ·
Replies
3

Stargazing Aurora Alert for 6th and 7th Sept

  • davenn
  • · Replies 6 ·
Replies
6

High School Does the Expansion of the Universe Affect Gravity?

  • Chris Miller
  • · Replies 87 ·
3
Replies
87

High School Expansion Propagation: Finite Seed vs Everywhere?

  • Grinkle
  • · Replies 9 ·
Replies
9

Undergrad Virial Theorem and the Ergodic hypothesis

  • JMatt7
  • · Replies 2 ·
Replies
2

High School How can the Big Bang model apply to the entire universe?

  • icantevenn
  • · Replies 21 ·
Replies
21

Undergrad Comparison of tidal forces acting on the Moon vs Enceladus

  • Vrbic
  • · Replies 56 ·
2
Replies
56

High School Uranus's Moon Cressida is Doomed

  • CygnusX-1
  • · Replies 5 ·
Replies
5

Stargazing Sunspots visible for 2 Sept 2017

  • davenn
  • · Replies 13 ·
Replies
13

High School Why does the Moon sometimes seem red?

  • Eleni_
  • · Replies 9 ·
Replies
9

High School What Theories Explain the Nature and Changes of Space?

  • sanpokhrel
  • · Replies 1 ·
Replies
1

High School See Asteroid Florence Tonight in Frankfurt Germany

  • lifeonmercury
  • · Replies 2 ·
Replies
2

Undergrad Understanding the Role of a(t)*dr in Calculating Actual Distance

  • Apashanka Das
  • · Replies 2 ·
Replies
2

Undergrad Ammonia in icy moons of gas giants

  • smartalek86
  • · Replies 2 ·
Replies
2

High School Big Bang theory and the known universe

  • icantevenn
  • · Replies 29 ·
Replies
29

Undergrad Models of accretion disc emissions contradicted by experiment

  • Buzz Bloom
  • · Replies 5 ·
Replies
5

High School What is the age of the universe relative to?

  • Salvador Sosa
  • · Replies 8 ·
Replies
8

High School A Hypothesis To Observe The Formation Of Earth

  • asesena
  • · Replies 12 ·
Replies
12

High School Did the big bang create something from nothing?

  • Lunct
  • · Replies 26 ·
Replies
26

High School Is Our Observable Universe the Actual Size of Our Universe?

  • Lunct
  • · Replies 18 ·
Replies
18

High School Most detailed picture of Antares

  • mfb
  • · Replies 8 ·
Replies
8

High School What factors determine the timing of a solar eclipse?

  • arabianights
  • · Replies 3 ·
Replies
3

High School Asteroid Florence will soon pass Earth

  • tony873004
  • · Replies 1 ·
Replies
1

Stargazing The Sun today - 9 July 2017 - nice spot group

  • davenn
  • · Replies 37 ·
2
Replies
37

High School Why Didn't the Earth Go Dark During Today's Solar Eclipse?

  • rasp
  • · Replies 21 ·
Replies
21

Stargazing 'losing light' 1.25" DSLR coupling vs 2"?

  • mishima
  • · Replies 5 ·
Replies
5

Graduate Definition of [itex]\sigma_8[/itex]

  • Einj
  • · Replies 5 ·
Replies
5

Undergrad Why not detect dark matter in our own galaxy?

  • alejandromeira
  • · Replies 12 ·
Replies
12

Stargazing 2 significant spot groups currently visible

  • davenn
  • · Replies 10 ·
Replies
10

High School Are Gravitational Waves accepted?

  • nmsurobert
  • · Replies 3 ·
Replies
3

High School Is it possible to see sunspots with the unaided eye?

  • BenAS
  • · Replies 15 ·
Replies
15

High School If spacetime can be bent can it be broken?

  • Wallsy
  • · Replies 14 ·
Replies
14

Undergrad Galaxy Rotation Curves: Newton's Shell Theorem Impact

  • redtree
  • · Replies 19 ·
Replies
19

Undergrad Observable Universe Size in Different Perspectives

  • Arman777
  • · Replies 42 ·
2
Replies
42

Stargazing Cloud of Moving Stars: Astronomy Phenomenon I Just Saw

  • tonyxon22
  • · Replies 32 ·
2
Replies
32

Stargazing Solar Con? Eclipse road trip to Makanda Illinois

  • Blank_Stare
  • · Replies 40 ·
2
Replies
40

Undergrad Eclipse Path Explained: Earth's Axis & Moon's Incline

  • TheWonderer1
  • · Replies 7 ·
Replies
7

High School Age of the universe: observable or entire universe?

  • Oink Honey
  • · Replies 56 ·
2
Replies
56

Stargazing Protecting Optics (not eyes) During Solar Observing

  • mishima
  • · Replies 20 ·
Replies
20

Undergrad Hawking radiation from de Sitter horizon

  • durant35
  • · Replies 8 ·
Replies
8

High School What if we weren't the only Big Bang

  • clockwork_fox12
  • · Replies 3 ·
Replies
3

High School Capture in a 2-body system (not)

  • DaveC426913
  • · Replies 2 ·
Replies
2

Stargazing Welding glasses safe to view eclipse with?

  • dotancohen
  • · Replies 13 ·
Replies
13

Undergrad How to model Solar System formation accurately and realistically

  • Joshua Benabou
  • · Replies 6 ·
Replies
6

High School Question about the shape of the Universe

  • Pgottsha84
  • · Replies 8 ·
Replies
8

Graduate GADGET2 Simulations: Fixing N-GenIC Error

  • Plaetean
  • · Replies 3 ·
Replies
3

High School Goldilocks zones of other parameters

  • Suppaman
  • · Replies 13 ·
Replies
13

Undergrad Influence of Dark Energy and curvature in photon-baryon fluid?

  • DoobleD
  • · Replies 4 ·
Replies
4

High School A thought on the expansion of the Universe

  • Igottaknow
  • · Replies 2 ·
Replies
2

Undergrad How fast is the Universe expanding?

  • hugostrange
  • · Replies 16 ·
Replies
16

Stargazing Different Simultaneity for telescopes in space and earth?

  • ofirg
  • · Replies 2 ·
Replies
2

Undergrad Mysterious Agent Blows Up Moon: Can Earth Survive?

  • Sherwood Botsford
  • · Replies 9 ·
Replies
9

Undergrad Why isn't the Planck-scale limit taken as a postulate?

  • Gerinski
  • · Replies 8 ·
Replies
8

Stargazing M8 Lagoon and M20 Trifid nebulae

  • davenn
  • · Replies 1 ·
Replies
1

High School Our galaxy hosts millions of Black Holes

  • wolram
  • · Replies 12 ·
Replies
12

High School Can gravitational waves interfere with each other?

  • KBon
  • · Replies 30 ·
2
Replies
30

Undergrad Why centrifuges on Earth and in space would be the same?

  • Cyber
  • · Replies 8 ·
Replies
8

Undergrad Is the Planck length a proper length?

  • jcap
  • · Replies 6 ·
Replies
6