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 History of the Earth's Axial Tilt

  • TheAzn
  • · Replies 2 ·
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2

Undergrad Does Higher Luminosity Mean Higher Power in Stars?

  • Mafia
  • · Replies 3 ·
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3

High School What is the actual colour of the Sun?

  • MegaDeth
  • · Replies 7 ·
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7

Graduate What proof do we have that TIME exists?

  • Homesick345
  • · Replies 149 ·
5
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149

Graduate Could Multiple Big Bangs and Dark Energy Explain the Expanding Universe?

  • Dsjodin
  • · Replies 21 ·
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21

Graduate CMB Peak Fregenucy (Planck's law vs. Wein's law)

  • redrum419_7
  • · Replies 1 ·
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1

Undergrad Infinite monkey theorem - question(s)

  • Thomas1989
  • · Replies 15 ·
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15

High School Is there any star not belonging to any galaxy?

  • wdlang
  • · Replies 5 ·
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5

Graduate Do theories of quantum gravity require that space-time is a lattice?

  • james.goetz
  • · Replies 2 ·
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2

Graduate How to calculate CBR lambda vs age of universe?

  • Fire Tech
  • · Replies 8 ·
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8

Undergrad Sun's North Magnetic Pole Begins to Flip, South Not Moving Yet

  • Dotini
  • · Replies 4 ·
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4

Graduate Was energy already quantized 10^-43 seconds after the Big Bang?

  • CarlosLara
  • · Replies 2 ·
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2

Undergrad Relationship between expanding universe and time

  • 00Svo
  • · Replies 26 ·
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26

Graduate Need help with Gravitational Constant (G)

  • eggman100
  • · Replies 6 ·
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6

Graduate Could Anti-Dark Energy and Matter Exist in the Universe?

  • Some Slacker
  • · Replies 10 ·
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10

Graduate Geometry of Inflationary Universe?

  • Octavianus
  • · Replies 1 ·
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1

High School Write a Speech: "Time Waits for No One" & Cosmology

  • AHUGEMUSHROOM
  • · Replies 2 ·
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2

Graduate Calculating the direction of the center of the universe?

  • Throstur
  • · Replies 9 ·
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9

Graduate The Role of Inflation in the Expansion of the Universe

  • N3Wparadigm
  • · Replies 20 ·
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20

Graduate Can we extend our inertial frame globally?

  • johne1618
  • · Replies 5 ·
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5

Graduate Is there a limit on the rotational speed of fast spinning pulsars?

  • tigerstef
  • · Replies 28 ·
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28

Graduate What Are the Key Theories Behind the Multiverse Concept?

  • swiss_rebel
  • · Replies 1 ·
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1

Graduate Size of the Universe just after Big Bang

  • Steely Dan
  • · Replies 19 ·
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19

Undergrad How did elements and building blocks of life arrive on Earth?

  • Aziza
  • · Replies 6 ·
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6

Graduate Will space always expand when the space has vacuum energy and zero mass?

  • james.goetz
  • · Replies 5 ·
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5

Graduate How to Determine the Mass of an AGN from Solar Luminosity?

  • tomjennings
  • · Replies 6 ·
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6

Graduate Why such strange units of measure?

  • JArnold
  • · Replies 3 ·
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3

What is your opinion on John C. Mather

  • Futuregen600
  • · Replies 7 ·
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7
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4

Graduate Cosmological redshift alternative explanation?

  • Aidyan
  • · Replies 5 ·
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5

High School Hubble's Misconception and the Discovery of Other Galaxies within Our Universe

  • hankaaron
  • · Replies 14 ·
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14

Undergrad Undergraduate research topic help?

  • C0smiicV0r3ex
  • · Replies 3 ·
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3

Graduate Neutron stars not sustained by degeneracy force?

  • dalcde
  • · Replies 1 ·
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1

Graduate Orbit Determination for Dummies Another hillbilly tutorial.

  • Jenab
  • · Replies 20 ·
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20

Graduate Big Bang vs Big Crunch: Universe w/No End

  • robert nies
  • · Replies 2 ·
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2

Graduate Cherenkov detector on a venus orbiter (Venera 9)

  • hangainlover
  • · Replies 2 ·
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2

Undergrad Radio doppler experiment (astro)

  • hangainlover
  • · Replies 3 ·
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3

Undergrad Understanding Local Standard of Rest for Astronomy Exam

  • mikerodeman
  • · Replies 8 ·
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8

Graduate What Insights Does the Fourth Dimension Offer About Our Universe?

  • timel0rd
  • · Replies 1 ·
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1

Graduate Density profile of Wolf Rayet stars

  • ajit.phys
  • · Replies 2 ·
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2

Graduate Why does the expansion of space in a uniform universe only push outward?

  • Farahday
  • · Replies 1 ·
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1

Graduate What's the precise relationship between Mass and Charge

  • sheshank
  • · Replies 9 ·
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9

Undergrad Limiting Magnitude of CCD Imaging

  • Drakkith
  • · Replies 14 ·
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14

Graduate Issues regarding the expansion of the Universe at the subatomic level

  • habarnam
  • · Replies 15 ·
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15

Graduate Origins of Scale Factor of FRW Metric and Misc Questions of GR Equations

  • ServusSomni
  • · Replies 16 ·
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16

Undergrad Elements on Earth: Supernova & Planets

  • yardtick
  • · Replies 6 ·
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6

Graduate Luneburg Lenses: Understanding Diffraction, Spill-over and Focusing

  • Jean Bickle
  • · Replies 5 ·
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5

Graduate How Can I Start Learning Numerical Simulations for Modeling Gamma-Ray Bursts?

  • ajit.phys
  • · Replies 4 ·
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4

Graduate Is gravity 'weak' because it leaks into higher dimensions?

  • B.Spinoza
  • · Replies 32 ·
2
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32

Undergrad Is There a Center to the Expanding Universe? And How Does Light Factor In?

  • allo4
  • · Replies 8 ·
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8

What is the mass of dark matter?

  • quantum12345
  • · Replies 3 ·
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3

Graduate Shouldn't we see faster expansion without dark energy

  • KeplerJunior
  • · Replies 6 ·
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6

Graduate What's Behind Dark Matter/Energy? What We're Missing

  • RK7
  • · Replies 11 ·
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11

High School What is the opposite of a supernova

  • cre8flow
  • · Replies 24 ·
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24

Graduate Understanding Black Holes: Perspectives and Questions

  • Thunderclap
  • · Replies 1 ·
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1

High School How do I find the age of a star?

  • ageorge95
  • · Replies 49 ·
2
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49

Graduate Question about the formation of a massive star

  • ldc3
  • · Replies 6 ·
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6

Graduate Slightly Modified Olbers Paradox Question

  • SHawking
  • · Replies 2 ·
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2

Undergrad Why Doesn't the Universe Explode Because of an Antimatter Reaction?

  • AntiPhysics
  • · Replies 14 ·
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14

Graduate Varying Fine Structure Constant and Vacuum Energy Density

  • asimov42
  • · Replies 8 ·
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8

Undergrad Is it possible to find our Sun's siblings?

  • saros
  • · Replies 12 ·
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12

Undergrad Massive Stars Spin Faster: The Reason Explained

  • Sean Pan
  • · Replies 5 ·
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5

Undergrad Visibility of Venus during the march equinox

  • kaleidoscope
  • · Replies 3 ·
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3

Graduate Metallicity and Stellar Formation

  • Drakkith
  • · Replies 3 ·
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3

Graduate Alternative theories being tested by Gravity probe B

  • Garth
  • · Replies 371 ·
13
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371

Graduate Did quantum degeneracy pressure drive inflation?

  • johne1618
  • · Replies 2 ·
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2

Undergrad Sending a rocket into space 75% less fuel.

  • uperkurk
  • · Replies 1 ·
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1

Graduate Is time just a perception of potential possibilities?

  • jaysteve
  • · Replies 3 ·
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3

Graduate Do Planck Units Remain Relevant Inside Black Holes?

  • BernieM
  • · Replies 9 ·
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9

How would you describe a black hole

  • cre8flow
  • · Replies 6 ·
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6

Undergrad Supernova in 2241 BC: Astronomer Views

  • cre8flow
  • · Replies 4 ·
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4

Undergrad Why does velocity not vary with distance within 10 Mpc?

  • em370
  • · Replies 4 ·
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4

Undergrad What Are Wormholes and How Do They Work?

  • Henzo
  • · Replies 16 ·
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16

Graduate How does the Big Bang Theory explain the creation of matter from energy?

  • John15
  • · Replies 51 ·
2
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51

Graduate Can the Moon sustain an atmosphere after terraforming?

  • Qshadow
  • · Replies 5 ·
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5

Graduate Are the Three Dimensions of Our Universe Independent?

  • jd12345
  • · Replies 1 ·
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1

High School Can Star Positions Be Accurately Predicted?

  • bignevermo
  • · Replies 6 ·
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6

Undergrad Is a Utah Petroglyph Evidence of the 1054 Supernova Observation?

  • ImaLooser
  • · Replies 3 ·
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3

Graduate Role of triatomic H ion (H3+) in early star formation

  • marcus
  • · Replies 1 ·
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1

Graduate Which fraction of the observed CMBR signal is due to some foreground contaminant

  • Tanelorn
  • · Replies 20 ·
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20

Graduate Spatial and temporal variation of alpha?

  • asimov42
  • · Replies 1 ·
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1

How do astrophysicists balance truth and creativity

  • cre8flow
  • · Replies 2 ·
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2

High School Does Light Really Stop and Turn Back When Reflected?

  • StevenJParkes
  • · Replies 2 ·
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2

Undergrad How is the big bang related to the general theory of relativity?

  • JJHK
  • · Replies 3 ·
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3

Graduate Can We Adjust Natural Constants to Obtain Stable Atoms in Other 'Multiverses'?

  • Aidyan
  • · Replies 13 ·
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13

Graduate Can Baryon Acoustic Oscillation Accurately Measure the Universe's Expansion?

  • bill alsept
  • · Replies 8 ·
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8

Graduate The 'nothingness' of the vacuum.

  • Naty1
  • · Replies 1 ·
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1

Graduate Does iron really kill fusion in stars?

  • ldc3
  • · Replies 5 ·
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5

Undergrad Follow-up and pipeline: definitions

  • RHK
  • · Replies 4 ·
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4

Graduate Hawking radiation and cosmic microwave background radiation

  • Orion1
  • · Replies 5 ·
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5

Graduate Obstacles to observing the cosmic neutrino background

  • bobsmith76
  • · Replies 1 ·
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1

Graduate Physical space properties questions

  • neginf
  • · Replies 8 ·
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8

High School Naked eye view from intergalactic space

  • Frankiewicz
  • · Replies 4 ·
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4

Graduate Does not receeding of galaxies decrease entropy

  • dpa
  • · Replies 1 ·
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1

High School Why Can We See Venus from Michigan?

  • dmayers94
  • · Replies 38 ·
2
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38

Graduate Is our universe a geodesically complete manifold?

  • TrickyDicky
  • · Replies 20 ·
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20

Graduate What is the issue with the concept of a center in the expanding universe?

  • Quinzio
  • · Replies 16 ·
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16

Undergrad Universe Expansion: Why Isn't Space Between Atoms Expanding?

  • Skeetss
  • · Replies 28 ·
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28

Undergrad Why do orbits become more eccentric when changing speed?

  • nothingbetter
  • · Replies 1 ·
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1

Graduate What can spectroscopy of this distant galaxy reveal about the universe at z~10?

  • Chronos
  • · Replies 5 ·
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5