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

Graduate Is dark energy actually zero-point energy?

  • jimjohnson
  • · Replies 4 ·
Replies
4

Graduate Testing Relativity: Spinning in Space - Feasible?

  • jreelawg
  • · Replies 6 ·
Replies
6

High School Does the earth translate around the sun?

  • nonequilibrium
  • · Replies 7 ·
Replies
7

Graduate Why Do Disk Galaxies Appear to Spin Despite Irregular Redshift Patterns?

  • TrickyDicky
  • · Replies 8 ·
Replies
8

Undergrad What Are the Competing Theories in Astrophysics: Dark Matter vs MOND?

  • Ironside
  • · Replies 1 ·
Replies
1

Graduate Galaxy at redshift z=8.6 (the actual paper)

  • marcus
  • · Replies 1 ·
Replies
1

Graduate How Is the Distance to the CMB Measured and How Does It Relate to Its Structure?

  • AutoToAlek
  • · Replies 2 ·
Replies
2

Graduate Does the universe need an escape velocity?

  • jhe1984
  • · Replies 12 ·
Replies
12

Graduate How Do Critical Density and CMB Irregularities Explain the Universe's Shape?

  • leatherneckpa
  • · Replies 2 ·
Replies
2

CERN scientists eye parallel universe breakthrough

  • Gaius Baltar
  • · Replies 2 ·
Replies
2

Stargazing Increasing the resolving power of a telescope

  • Idoubt
  • · Replies 1 ·
Replies
1

High School Could Gliese 581 Be Our Next Habitable Planet?

  • AfRoMaNn
  • · Replies 2 ·
Replies
2

Undergrad How is measuring Redshift possible?

  • timbreman
  • · Replies 8 ·
Replies
8

High School Ideas for High School Astrophysics Course Syllabus

  • kungfuscious
  • · Replies 8 ·
Replies
8

Undergrad New to astrophysics, don't have a good physics foundation, need some help

  • Aurealis
  • · Replies 7 ·
Replies
7

Graduate What are the limits of interstellar travel?

  • skippy1729
  • · Replies 44 ·
2
Replies
44

Undergrad *Quick moon question - (about orbit)

  • nukeman
  • · Replies 6 ·
Replies
6

Undergrad Formation of Stars: How Gas Spins to Fuel Birth

  • Sniperman724
  • · Replies 2 ·
Replies
2

Undergrad Is this angular size calculation correct?

  • nukeman
  • · Replies 1 ·
Replies
1

Undergrad Universe Origin: How Could Galaxy be 13B Light Years Away?

  • Trimike
  • · Replies 1 ·
Replies
1

Graduate How Does Gravity Work and What Causes Time to Slow Down Near a Black Hole?

  • temoisio
  • · Replies 10 ·
Replies
10

Graduate Superstring Cosmology: Compactifying 7 Dimensions

  • Kevin_Axion
  • · Replies 5 ·
Replies
5

Undergrad How do I normalize the likelihood distribution?

  • aymer
  • · Replies 8 ·
Replies
8

Undergrad Is the Big Bang Theory Debunked?

  • phoenixthoth
  • · Replies 55 ·
2
Replies
55

Stargazing Pictures I took at a 2.5m telescope in the Canary Islands

  • kungfuscious
  • · Replies 1 ·
Replies
1

Undergrad Are Wormholes the Key to Unlocking the Universe's Secrets?

  • 2rashmi1993
  • · Replies 6 ·
Replies
6

Graduate Could Dark Energy be Caused by a Slow Shift in the Base State?

  • Upisoft
  • · Replies 3 ·
Replies
3

Undergrad Calculating the Earth-Sun distance during perihelion

  • nukeman
  • · Replies 9 ·
Replies
9

Graduate Inflation and initial conditions

  • skydivephil
  • · Replies 2 ·
Replies
2

Graduate The Collision of Elliptical Galaxies: A Surprising and Promising Event

  • TrickyDicky
  • · Replies 2 ·
Replies
2

Stargazing What is the Best Catadioptric Telescope for Portability and Versatility?

  • procq
  • · Replies 4 ·
Replies
4

Undergrad Greenwich Mean Timt, GMT and Universal Coodinated Time, UT

  • Philosophaie
  • · Replies 2 ·
Replies
2

Question about having a Theory in astronomy. ?

  • nukeman
  • · Replies 16 ·
Replies
16

Undergrad Question about Objects in Ultra Deep Field

  • AdkinsJr
  • · Replies 3 ·
Replies
3

Stargazing Heyy, i've had a telescope before and know how to use them.Has

  • nickthrop101
  • · Replies 3 ·
Replies
3

High School Is Earth’s orbit far from circular?

  • nukeman
  • · Replies 1 ·
Replies
1

Stargazing What Are the Best Telescope Models Within the £100-£250 Range?

  • nickthrop101
  • · Replies 1 ·
Replies
1

Graduate Faster than Light Travel Side Effects

  • Ultrastar 1
  • · Replies 17 ·
Replies
17

Undergrad Black holes giving birth to stars?

  • discord73
  • · Replies 1 ·
Replies
1

Graduate How Do Stars Achieve Their Massive Sizes?

  • discord73
  • · Replies 1 ·
Replies
1

Graduate What are the Current Main Research Topics in Astrophysics?

  • ahmadfadl92
  • · Replies 1 ·
Replies
1

High School Question about Phases of the Moon. Thanks

  • nukeman
  • · Replies 13 ·
Replies
13

High School Is the Waning Crescent Visible Near the Horizon?

  • nukeman
  • · Replies 4 ·
Replies
4

High School What would happen if you fell into a black hole?

  • wangdang
  • · Replies 5 ·
Replies
5

Undergrad Tides & Moon Distance: Seeking Answers

  • kay89
  • · Replies 11 ·
Replies
11

Stargazing Aug 21st, 2017, a total solar eclipse will cross the US

  • Ivan Seeking
  • · Replies 29 ·
Replies
29

Graduate Dark matter and keplerian revolution

  • TrickyDicky
  • · Replies 19 ·
Replies
19

High School The Grand Design - Stephen Hawking and Leonard Mlodinow

  • yarixen
  • · Replies 5 ·
Replies
5

Graduate What Causes Hypervelocity Stars to Eject from Black Holes?

  • shnazzybox
  • · Replies 1 ·
Replies
1

Graduate Calculating Motion in a Three-Body Gravity System: Challenges and Solutions

  • Sakriya
  • · Replies 12 ·
Replies
12

Undergrad Calculating Gravities for Math to the Moon

  • nution
  • · Replies 2 ·
Replies
2

Undergrad From physics how can we figure out how old the earth and the universe is?

  • dcderek24
  • · Replies 7 ·
Replies
7

Graduate Can a "Dead Universe" be Revived?

  • geordief
  • · Replies 8 ·
Replies
8

Undergrad Astrometry and Elliptical orbits

  • Mu naught
  • · Replies 4 ·
Replies
4

Graduate How is the Final Velocity of Star Movements Calculated?

  • lenfromkits
  • · Replies 1 ·
Replies
1

Undergrad Can We Reach the Moon with a Slow, Steady Launch?

  • nution
  • · Replies 9 ·
Replies
9

Undergrad How Can We Determine the Size of a Black Hole?

  • fillipeano
  • · Replies 4 ·
Replies
4

Undergrad Could Heat Exchange Be the Reason Behind Earth's Spin?

  • JamiePocock
  • · Replies 3 ·
Replies
3

Undergrad Strange wikipedia entry about the sun's core

  • Fanaval
  • · Replies 3 ·
Replies
3

Graduate The infinite possobilities presented by the infinite amount of probabilities

  • dr.probable
  • · Replies 14 ·
Replies
14

High School Why are solar eclipses so short compared to lunar eclipses?

  • nukeman
  • · Replies 3 ·
Replies
3

Graduate Negative pressure and dark energy

  • relativityfan
  • · Replies 10 ·
Replies
10

Graduate Why smaller particles come together

  • A Dhingra
  • · Replies 6 ·
Replies
6

Graduate Colliding Black Holes: Will the Smaller Get Pulled In?

  • Worzel
  • · Replies 4 ·
Replies
4

Undergrad Define/explain this gravity calculation (picture)

  • nukeman
  • · Replies 4 ·
Replies
4

John Huchra Dies at 61; Maps Altered Ideas on Universe

  • diogenesNY
  • · Replies 1 ·
Replies
1

Graduate Can FLRW metric be taken to describe stretching in time rather than space?

  • themos
  • · Replies 2 ·
Replies
2

Graduate Quasar Alignment to Cosmic Strings

  • Kevin_Axion
  • · Replies 5 ·
Replies
5

Graduate Expanding Present Time Universe at Omega 0 = 1: Help Needed

  • knightq
  • · Replies 8 ·
Replies
8

Graduate Can a QM/GR overlap provide a breakthrough in understanding gravity?

  • Ran out of sp
  • · Replies 3 ·
Replies
3

Undergrad Galaxies on the Edge: Understanding the Expansion of the Universe

  • jimjohnson
  • · Replies 5 ·
Replies
5

Graduate What caused the expansion of the universe for the 1st 7 billion years?

  • mysearch
  • · Replies 10 ·
Replies
10

Graduate What is the relationship between mathematical structures and real existence?

  • PhanthomJay
  • · Replies 8 ·
Replies
8

Graduate Is the Expansion of the Universe Driven by Mass?

  • wolram
  • · Replies 22 ·
Replies
22

Graduate What is the energy of the galactic magnetic field? (E/c^2)

  • MTd2
  • · Replies 1 ·
Replies
1

Graduate Plotting Intensity in Airy Pattern of Telescope - 1D

  • theneedtoknow
  • · Replies 1 ·
Replies
1

Graduate Cosmological Constant: Dark Energy vs Gravity Ratio

  • Ikoro
  • · Replies 18 ·
Replies
18

Graduate Are Distant Globular Clusters the Key to Testing Newtonian Gravity?

  • inflector
  • · Replies 19 ·
Replies
19

Graduate If Big Crunch = True, then Reincarnation = True?

  • SeventhSigma
  • · Replies 18 ·
Replies
18

Graduate Subatomic particle and space curvature

  • richerrich
  • · Replies 10 ·
Replies
10

Graduate Origin of Dark Energy: Before the Big Bang

  • richerrich
  • · Replies 7 ·
Replies
7

Graduate How many methods for dating a galaxy

  • lenfromkits
  • · Replies 1 ·
Replies
1

Graduate Was the Universe Really Chaotic Right After the Big Bang?

  • Descartz2000
  • · Replies 15 ·
Replies
15

High School Super black holes and stars orbiting them

  • littlebanger
  • · Replies 16 ·
Replies
16

Graduate Super-black holes and the universe

  • gta-maloy]
  • · Replies 11 ·
Replies
11

Graduate Explore the Possibility of Other Universes with Hawking's "The Grand Design

  • PhanthomJay
  • · Replies 11 ·
Replies
11

Undergrad Was the Moon Ever Touching Earth Billions of Years Ago?

  • dcderek24
  • · Replies 10 ·
Replies
10

Graduate State of matter before a black hole is formed.

  • conan
  • · Replies 16 ·
Replies
16

Graduate Pressure in stars from photons vs. electron/positron pairs

  • PAllen
  • · Replies 5 ·
Replies
5

Undergrad Degeneracy pressure and interactions

  • relativityfan
  • · Replies 7 ·
Replies
7

High School What Are Some Math-Based Topics for an Astrophysics Project?

  • Fragment
  • · Replies 1 ·
Replies
1

Graduate Dark Energy, Light, the Universe, and Black Holes

  • bredmond812
  • · Replies 4 ·
Replies
4

Undergrad Angular size of Venus: Is my math correct?

  • nukeman
  • · Replies 9 ·
Replies
9

Graduate Some questions about energy conservation

  • Upisoft
  • · Replies 2 ·
Replies
2

High School *Quick question: When is VENUS visable in the sky in this period ?

  • nukeman
  • · Replies 14 ·
Replies
14

Graduate Why Doesn't Light from the Big Bang Get Stretched Out?

  • leonstavros
  • · Replies 10 ·
Replies
10

Undergrad Coordinates of Planets: An Astronomer's Guide

  • t_n_p
  • · Replies 6 ·
Replies
6

Graduate Will the Planck Satellite Illuminate Loop Quantum Cosmology Insights?

  • skydivephil
  • · Replies 7 ·
Replies
7

High School Tele Vue / Meade laser test: question

  • cyber3d
  • · Replies 5 ·
Replies
5

Undergrad Using Sloan Digital Sky Survey to find Planets

  • daveed
  • · Replies 2 ·
Replies
2