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 Can an Observer Safely Enter and Observe the Singularity Inside a Black Hole?

  • davidschmid10
  • · Replies 6 ·
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6

Graduate Is Light in a Perfectly Reflecting Box Redshifted Over Billions of Years?

  • Yoo
  • · Replies 18 ·
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18

Does the Universe Operate on Mathematical Logic?

  • th3plan
  • · Replies 18 ·
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18

Graduate Effects of Tensor + Scaler gravity

  • captn
  • · Replies 5 ·
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5

Graduate How Does Space-Time Influence the Fall of an Apple?

  • thinker93
  • · Replies 5 ·
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5

High School Water on Enceladus - Cassini's Revealing Findings

  • wolram
  • · Replies 5 ·
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5

Graduate Space Expansion and Light question

  • hagendaz
  • · Replies 5 ·
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5

Graduate Questions About Black Holes & Event Horizons

  • Charlie G
  • · Replies 6 ·
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6

Graduate Is Dark Energy Usable for Energy Extraction?

  • Coin
  • · Replies 25 ·
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25

Graduate Why include -xi*H in the equation of state?

  • odd-socks
  • · Replies 2 ·
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2

Graduate Could Our Universe Be Inside a Black Hole?

  • Nel
  • · Replies 1 ·
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1

Undergrad Explaining Expanding Universe: Galaxies Moving Away

  • electerr
  • · Replies 7 ·
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7

Graduate Super hubble and subhorizon fluctuations

  • aristurtle
  • · Replies 2 ·
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2

High School Direction of the gravtional force on the earth

  • tnutty
  • · Replies 3 ·
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3

Undergrad Equation to find the speed of a distant star

  • DeepSeeded
  • · Replies 11 ·
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11

Unusual Redness of Betelgeuse: A Mystery in the Night Sky?

  • scupydog
  • · Replies 11 ·
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11

Graduate Can Inter-Universe Energy Transfer Create New Realities?

  • CozmicScott
  • · Replies 2 ·
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2

Graduate What happens to a Black hole when they die?

  • Rashid
  • · Replies 17 ·
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17

Graduate Studying the formation of the very first stars

  • marcus
  • · Replies 0 ·
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0

Undergrad Is the Sun's Gravity Enough to Propel Objects to the Corona?

  • lubuntu
  • · Replies 11 ·
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11

Graduate Black Holes have no gravity below the event horizon? - How can that be?

  • Dusty_Matter
  • · Replies 19 ·
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19

The Next Naked Eye Comet: What to Expect & When

  • Stratosphere
  • · Replies 12 ·
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12

Undergrad Could the Universe Be Collapsing Without Our Knowledge?

  • ONON
  • · Replies 3 ·
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3

Undergrad Sir Author Eddington and Einstein's GTR

  • plutoisacomet
  • · Replies 3 ·
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3

Graduate Can Black Holes Decay and How Does This Affect Their Event Horizon?

  • Haibara Ai
  • · Replies 4 ·
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4

Fantastic astrophotograpy book now out

  • turbo
  • · Replies 1 ·
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1

Undergrad Why Is a Single Wavelength Used to Calculate Hubble's Diffraction Limit?

  • TheMan112
  • · Replies 8 ·
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8

Asteroid 2009 DD45: Close Approach to Earth March 2nd

  • Waveform
  • · Replies 2 ·
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2

Graduate The True Age of the Universe: Can We Ever Know It?

  • christian_dude_27
  • · Replies 15 ·
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15

Graduate How Do We Know Time, Space, and Matter Were Created in the Universe?

  • redhedkangaro
  • · Replies 4 ·
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4

Undergrad What would happen to Earth's orbit if it increased in mass or lost velocity?

  • GordonDengyo
  • · Replies 2 ·
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2

Graduate What will happen to Earth when hit by a Neutron Star at the Speed of Light?

  • Zdenka
  • · Replies 41 ·
2
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41

Undergrad Black Holes: Is the Hubble Image Real?

  • dtmmfam
  • · Replies 9 ·
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9
  • Poll Poll

Are Visitors from Outerspace Likely To Be Friendly?

  • Mammo
  • · Replies 22 ·
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22

Graduate HII regions, on-the-spot approximations

  • sarahrose
  • · Replies 2 ·
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2

High School Why Aren't Meteors Heated by Friction?

  • pixel01
  • · Replies 2 ·
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2

High School How gravity make planet to rotate?

  • freeman1879
  • · Replies 8 ·
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8

High School Beginner Astronomy: Telescope Advice & Tips

  • Charlie G
  • · Replies 6 ·
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6

Undergrad Space in an Atom: What is the Nature of this Space?

  • vibjwb
  • · Replies 3 ·
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3

Graduate Constant k in Friedman Equation Explained

  • wolfram
  • · Replies 5 ·
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5

Graduate Is Discrete Scale Relativity the Missing Piece of Einstein's Part III?

  • Knecht
  • · Replies 2 ·
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2

Stargazing in Georgia: Left or Right?

  • kimhen1
  • · Replies 3 ·
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3

Graduate The Structure of the Cosmos: A Map Revealing the Intricacies of Our Universe

  • discord73
  • · Replies 5 ·
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5

Undergrad Can someone explain curved space time?

  • Djrob99
  • · Replies 7 ·
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7

Graduate Gravity has to have an effect on time,when gravity can curve space ,it

  • monty37
  • · Replies 8 ·
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8

High School Are There Stars Made of Something Other Than Hydrogen?

  • discord73
  • · Replies 11 ·
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11

Astrophysicist Jobs: What's Available?

  • wiiyogi
  • · Replies 2 ·
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2

Undergrad Calculating Orbital Velocity for a Satellite Orbiting Earth

  • .:Endeavour:.
  • · Replies 2 ·
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2

Graduate How much does dust affect light from high redshift quasars?

  • oldman
  • · Replies 3 ·
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3

Graduate Accelerating Universe Expansion: Big Bang or Repulsive Force?

  • Chalk
  • · Replies 2 ·
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2

Graduate Big bang, little bangs, or sontaneous creation?

  • Peter Watkins
  • · Replies 14 ·
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14

Graduate Is the Cosmic Microwave Background a Picture of the Universe's Past?

  • electerr
  • · Replies 5 ·
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5

High School Is 2009 Really the Year of Astronomy?

  • mjsd
  • · Replies 5 ·
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5

Graduate Sun's Corona Paradox: Temperature Defying Laws of Thermodynamics

  • Je m'appelle
  • · Replies 3 ·
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3

Graduate Can We Detect Moons Around Earth-Sized Exoplanets?

  • 888eddy
  • · Replies 5 ·
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5

Graduate A Structure Larger than the Sloan Great Wall?

  • Petradog
  • · Replies 5 ·
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5

Graduate Can Balloons and Foam Revolutionize Our Understanding of Cosmology?

  • Ich
  • · Replies 1 ·
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1

Graduate Could a Moon Be Transformed into a Mini Sun?

  • bcohen1
  • · Replies 3 ·
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3

High School Is the Sun Anchored? | Experiments & Feedback

  • Oscar Wilde
  • · Replies 8 ·
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8

Undergrad What is singularity? [Black Hole ]

  • jasmine
  • · Replies 15 ·
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15

Undergrad Is this the approximate gravity of Mars?

  • .:Endeavour:.
  • · Replies 3 ·
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3

Graduate Big Bang Predictions - Exploring Energy Density & Expansion Rate

  • electerr
  • · Replies 3 ·
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3

Graduate Singularity - Black Hole or Naked

  • mathman
  • · Replies 19 ·
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19

Graduate Confused about monochromatic flux

  • constellation
  • · Replies 1 ·
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1

Graduate Friction in space as approaching light speed

  • Jackslap
  • · Replies 25 ·
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25

Graduate Observing antiquark annihilation

  • gtring
  • · Replies 1 ·
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1

Graduate Possible website title: The Origin of the Universe: A Scientific Inquiry

  • hadeka
  • · Replies 19 ·
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19

Undergrad Is the Red-Shift of Galaxy Spectra Evidence for the Expanding Universe?

  • Peter Watkins
  • · Replies 6 ·
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6

Undergrad Is the Big Crunch Inevitable in the Fate of Our Universe?

  • Ollie_G
  • · Replies 3 ·
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3

Graduate Perpetuum mobile: tying galaxies together?

  • AxelBoldt
  • · Replies 19 ·
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19

Undergrad Can Aliens Observe Plato Lecturing in Academia?

  • grasp
  • · Replies 12 ·
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12

Stargazing Kepler Telescope is so productive?

  • pixel01
  • · Replies 9 ·
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9

Undergrad Does Physics Predict How the Universe Will End?

  • JeffNYC
  • · Replies 4 ·
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4

Graduate Understanding the 4-Dimensional Universe Expansion: A Philosopher's Perspective

  • ronald_dai
  • · Replies 1 ·
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1

Graduate How Do Large Galaxy Fluctuations Challenge Standard Cosmological Models?

  • wolram
  • · Replies 12 ·
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12

Undergrad Why Do Orbits Take an Elliptical Shape?

  • koolraj
  • · Replies 2 ·
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2

Graduate Friction necessary for planet formation?

  • AxelBoldt
  • · Replies 3 ·
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3

Graduate Does Gravity from Other Universes Affect Our Universe?

  • Chirios
  • · Replies 3 ·
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3

Graduate Dark Energy, Distance to Galaxies and Distance in time.

  • discord73
  • · Replies 3 ·
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3

Stargazing Saturn with new DMK, grayscale camera

  • russ_watters
  • · Replies 10 ·
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10

Undergrad What is the magnitude of the magnetic field in solar wind?

  • Philosophaie
  • · Replies 1 ·
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1

Undergrad How do we tell how far away a gamma burst was?

  • pellman
  • · Replies 10 ·
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10

Graduate Are black holes and quantum entanglement interconnected in cosmological studies?

  • sirchasm
  • · Replies 3 ·
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3

Graduate The Computational Universe: Debunking the Myth or Proving the Possibility?

  • sirchasm
  • · Replies 50 ·
2
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50

Undergrad Why Are Planetary Orbits in Our Solar System Mostly Coplanar?

  • Archosaur
  • · Replies 3 ·
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3

Undergrad Question about orbit determination with find_orb

  • vacan
  • · Replies 1 ·
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1

Graduate Is the Universe Really Expanding or Just an Optical Illusion?

  • Peter Watkins
  • · Replies 9 ·
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9

Graduate Ages of Stars from CMD: The Accuracy of CMD vs. Photometry Explained

  • randa177
  • · Replies 7 ·
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7

Graduate Are Gamma Ray Bursts a Threat to Life on Earth?

  • Paolo 2008
  • · Replies 8 ·
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8

Graduate Inconsistency in Concordance Model?

  • JuanCasado
  • · Replies 12 ·
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12

Graduate Big Bang - Gravitational field of antimatter + matter before annihilation

  • Keijo
  • · Replies 9 ·
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9

Stargazing Has an astronaut ever captured a photo of a solar eclipse from space?

  • natski
  • · Replies 2 ·
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2

Graduate Why does a universe with a spherical geometry have to be finite?

  • Jack_O
  • · Replies 13 ·
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13

Graduate Mathematical principle for decomposing metric fluctuation

  • aristurtle
  • · Replies 6 ·
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6

Graduate Precession betrays Nemesis position?

  • Andre
  • · Replies 7 ·
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7

Graduate Dark Matter: An Unexplained Mystery

  • wolram
  • · Replies 1 ·
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1

Graduate Can dark energy be converted into dark mass?

  • pentazoid
  • · Replies 3 ·
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3

Graduate How many exoplanets with an atmospheric oxygen signature would be necessary?

  • zankaon
  • · Replies 13 ·
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13

High School Creating oxygen(co2) out Of hydrogen

  • athrax
  • · Replies 5 ·
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5

Graduate Is the universe truly isotropic at its boundary?

  • slipknotFor
  • · Replies 12 ·
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12