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 FRW pertubations in overdense and underdense regions

  • center o bass
  • · Replies 1 ·
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1

Undergrad Would the sky be red if the atmosphere was thicker?

  • willstaruss22
  • · Replies 9 ·
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9

Graduate Non equilibrium boson distribution function

  • center o bass
  • · Replies 1 ·
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1

Graduate If the sun becomes a black hole will its schwarzschild radius change?

  • avito009
  • · Replies 2 ·
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2

Undergrad What is the significance of the foci in gravitational orbits?

  • MattWakes
  • · Replies 2 ·
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2

Undergrad Which Has A Stronger Gravitational Pull - A Black Hole or Neutron Star?

  • Uberhulk
  • · Replies 5 ·
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5

High School I saw the 23 Oct 2014 N America partial solar eclipse

  • lpetrich
  • · Replies 2 ·
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2

Graduate Why two terms "Dark Energy" and "Dark Matter"

  • atuldpatil
  • · Replies 2 ·
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2

"Churning galaxy boasts a fiery halo of baby stars"

  • Spinnor
  • · Replies 1 ·
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1

Graduate Photon's History: Quantum Expression for Energy Loss with Scale Factor Increase

  • anorlunda
  • · Replies 9 ·
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9

High School Trying to understand the universe .possible at 13 years old?

  • canutej
  • · Replies 12 ·
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12

Graduate White dwarf mass-radius relationship

  • MattWakes
  • · Replies 7 ·
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7

High School Boundaries between the Constellations

  • Philosophaie
  • · Replies 2 ·
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2

Graduate Can black holes hold the key to the origin of our universe?

  • wolram
  • · Replies 1 ·
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Graduate Origin of our universe 4D black hole

  • StonedPhysicist
  • · Replies 33 ·
2
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33

Undergrad Were all galaxies quasars when they were young?

  • Robin
  • · Replies 2 ·
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2

Graduate Dark matter possibly explained by axions?

  • Tanelorn
  • · Replies 19 ·
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19

High School Moon Phases: Rise & Set Timings & Direction Explained

  • ajay.05
  • · Replies 3 ·
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3

Undergrad I require help with understanding beginner astronomy questions.

  • SigmaOctans
  • · Replies 4 ·
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4

Graduate How is the Rotational Velocity of Galaxies Measured?

  • ChrisVer
  • · Replies 3 ·
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3

Graduate Why do large elliptical galaxies not collapse due to their gravity?

  • Tanelorn
  • · Replies 8 ·
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8

Undergrad Is Infinite Space the Key to Understanding the Big Bang?

  • DHooley
  • · Replies 16 ·
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16

Graduate Does cosmic time (or comoving clock) run at the same pace at all times?

  • Vincentius
  • · Replies 23 ·
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23

Undergrad How Stars Ignite - The Fusion Reaction

  • avito009
  • · Replies 13 ·
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13

Graduate Are High Z SNe Brighter than LCMD Predicts?

  • RCopernicus
  • · Replies 1 ·
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1

Graduate Current Research on Communication Between Universes?

  • Mandy mae
  • · Replies 8 ·
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8

Undergrad Determine the least value of declination of stars so that stars can be seen?

  • nicolauslamsiu
  • · Replies 3 ·
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3

Graduate Can a Balloon Float Inside a Hollow, Air-Filled Space Elevator?

  • udtsith
  • · Replies 4 ·
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4

Graduate Why do black holes vanish over time?

  • NTW
  • · Replies 16 ·
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16

Undergrad What's the scale on Mars rover "Microscopic Imager" images ?

  • B0b-A
  • · Replies 2 ·
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2

Graduate Measuring Cosmic Rays: There's an App for that

  • TumblingDice
  • · Replies 1 ·
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1

High School Uranus' closest approach to earth and its interval

  • BOAS
  • · Replies 4 ·
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4

Graduate What exactly is the Hubble parameter?

  • 21joanna12
  • · Replies 7 ·
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7

Undergrad Kepler's 3rd Law: Solving Questions & Math

  • mh8780
  • · Replies 3 ·
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3

Graduate Dark Matter does not exist, what do you think?

  • wolram
  • · Replies 59 ·
2
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59

Graduate Lagrange Point and orbital velocity

  • _Stew_
  • · Replies 2 ·
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2

What would you do if you were in space

  • Mitxigan
  • · Replies 1 ·
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1

Undergrad What Are the Mysteries of the Universe We Still Need to Understand?

  • CKaiser1985
  • · Replies 9 ·
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Graduate Is the universe NOT accelerating ?

  • fencewalker
  • · Replies 5 ·
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5

Graduate Proof that black holes do not destroy information

  • Ipquarx
  • · Replies 2 ·
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2

High School Solar Cycle: Current State & Update

  • !Jon Snow!
  • · Replies 5 ·
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5

Undergrad How can I determine right ascension and declination of a star in the sky?

  • r m williams
  • · Replies 4 ·
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4

Total Lunar Eclipse 8th Oct 2014

  • davenn
  • · Replies 23 ·
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23

Graduate What is the true purpose of inflation in the early universe?

  • CKH
  • · Replies 41 ·
2
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41

Stargazing Is a Geo Stationary Satellite the Key to Building the World's Biggest Telescope?

  • gaurav0751
  • · Replies 10 ·
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10

Graduate What is the Visible Mass of the Milky Way?

  • RCopernicus
  • · Replies 4 ·
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4

Graduate Galaxy Formation: Searching for Primordial Origins

  • wolram
  • · Replies 29 ·
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29

Graduate Inertia in Space: Opening a Hatch

  • Prof Null
  • · Replies 13 ·
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13

Graduate ULXs & Black Holes: Unveiling Secrets of Escape Velocity

  • Dryson
  • · Replies 6 ·
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6

Graduate Is Dark Matter Only Interacting Through Gravity or Are There Other Theories?

  • Ciro Spaciari
  • · Replies 19 ·
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19

Graduate Can There Be Time Without Space? A Question for Discussion

  • iDimension
  • · Replies 3 ·
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3

Graduate Calculating Exoplanet Habitability using Stefan-Boltzmann Law | Habitable Zones

  • |Glitch|
  • · Replies 15 ·
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15

Graduate Why does light travel radially in the FRW universe?

  • center o bass
  • · Replies 5 ·
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5

Graduate Is there an unseen part of the universe older than the known universe?

  • cjackson
  • · Replies 3 ·
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3

Graduate Big Bang, big rip, lQc, has anyone ever run a computer simulation?

  • yoda-morpheus
  • · Replies 5 ·
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5

Undergrad Introdutions to mathematical astronomy?

  • moriheru
  • · Replies 1 ·
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1

Undergrad Reynolds Number and Turbulence in Atmospheric Boundary Layers

  • Martina835
  • · Replies 4 ·
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4

Graduate Could the Big Bang be related to the flow of current in vacuum tubes?

  • Dryson
  • · Replies 7 ·
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7

Graduate Why does inflation generate gravity waves?

  • thecommexokid
  • · Replies 5 ·
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5

Graduate Was the CMB Radiation Predicted or Post-Dicted by Big Bang Cosmology?

  • AdkinsJr
  • · Replies 28 ·
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28

Undergrad Does the observable universe support the idea of circular math?

  • Physics_Kid
  • · Replies 7 ·
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7

Graduate Is a Connection Between Black Holes and Time Machines Possible?

  • Sandhani Boruah
  • · Replies 4 ·
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4

Graduate Dark Matter: Why doesnt dark matter coalesce 'into' Ordinary Matter - Repost

  • curiouschris
  • · Replies 9 ·
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9

Undergrad Black Holes Colliding: Evidence & Expectations

  • Johan0001
  • · Replies 3 ·
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3

Graduate Mass Profile in Elliptical Galaxies

  • RCopernicus
  • · Replies 1 ·
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1

Graduate Where Is Dark Matter in the Universe?

  • curiouschris
  • · Replies 15 ·
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15

Graduate I don't believe in singularities

  • omegabeta
  • · Replies 10 ·
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10

Graduate Relationship between Ultracold neutrons and neutron stars

  • skujesco2014
  • · Replies 6 ·
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6

Graduate A Question Concerning Solar Flares

  • |Glitch|
  • · Replies 8 ·
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8

Graduate Are neutrons in a neutron star relativistic?

  • skujesco2014
  • · Replies 15 ·
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15

Graduate Is the Universe Actually Collapsing Instead of Expanding?

  • stefanow
  • · Replies 8 ·
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8

Graduate Making basic astro/cosmo calculations easy with google calculator--examples

  • marcus
  • · Replies 2 ·
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2

Can Microorganisms Help Us Understand Aging Rates on Other Planets?

  • ozzlight
  • · Replies 4 ·
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4

Graduate Can You Orbit the Photon Sphere Without Being Pulled into the Event Horizon?

  • avito009
  • · Replies 2 ·
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2

Undergrad Is it accurate to say 99% of the universe is pure black with no sound?

  • zeromodz
  • · Replies 4 ·
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4

Graduate When Was the Universe's Expansion Rate Zero?

  • SteveK2
  • · Replies 53 ·
2
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53

Graduate Dark Energy an effect of inhomogeneity?

  • CKH
  • · Replies 5 ·
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5

Graduate Beginning of accelerating expansion

  • hendoS
  • · Replies 3 ·
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3

Graduate Missing low-metalicity Red Dwarves

  • RCopernicus
  • · Replies 1 ·
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1

Graduate Why is temperature inversely proportional to the horizon's area?

  • David Carroll
  • · Replies 7 ·
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7

Graduate How did massive black holes form and grow in the early universe?

  • wolram
  • · Replies 16 ·
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16

Undergrad Could Super-Bacteria from Space Pose a Threat to Earth?

  • Dryson
  • · Replies 1 ·
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1

Undergrad Gravitational Lens with home scope?

  • mishima
  • · Replies 2 ·
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2

Graduate Unraveling the Mysteries of Dark Energy and Dark Matter in the Universe

  • gianeshwar
  • · Replies 6 ·
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6

Graduate Where can I find an updated Milky Way density profile for my simulation?

  • RCopernicus
  • · Replies 4 ·
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4

Graduate Who should we give credit for considering the possibility of Black Hole?

  • avito009
  • · Replies 6 ·
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6

Graduate Infinite Regress | Why is everyone telling me I am wrong?

  • iDimension
  • · Replies 40 ·
2
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40

Graduate How far from Event horizon are you safe?

  • avito009
  • · Replies 7 ·
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7

Graduate Is hyperbolic space consistent with homogeneity?

  • center o bass
  • · Replies 4 ·
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4

Graduate Why is stellar ash found in the core of a White Dwarf so dense?

  • avito009
  • · Replies 2 ·
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2

Graduate The fabric of the cosmos - Universe or Multiverse

  • benlahbib
  • · Replies 2 ·
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2

Graduate How can black holes coexist with the expanding universe?

  • Grajek
  • · Replies 22 ·
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22

Graduate Gravity and Gas Pressure on an Accelerating Object

  • Dryson
  • · Replies 2 ·
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2

Graduate Can another blackhole pull you out of the event horizon of a blackhole

  • maa105
  • · Replies 34 ·
2
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34

Graduate Horizon distance at last scattering surface

  • Orodruin
  • · Replies 6 ·
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6

Graduate Spiral Galaxies as Gravity Lense

  • RCopernicus
  • · Replies 3 ·
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3

Graduate Explore Laniakea: The Supercluster Earth is in

  • Astronuc
  • · Replies 1 ·
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1

Undergrad How does solar wind effects Geomagnetic Field?

  • space0
  • · Replies 5 ·
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5

Stargazing UY Scuti, the biggest known star, viewed through a telescope

  • Haktarfone
  • · Replies 6 ·
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6