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

Undergrad Astronomer107 and the surface gravity of a black hole

  • marcus
  • · Replies 1 ·
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1

Graduate What's your favorite brief survey of modern cosmology?

  • marcus
  • · Replies 1 ·
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1

Stargazing Check Out the Lunar Eclipse Tonight - Night Calculator

  • kyle_soule
  • · Replies 5 ·
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5

Graduate Question re GP-3 orbiting gyroscopes test of relativity

  • marcus
  • · Replies 2 ·
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2

Graduate Z/A in the Chandrasekhar formula

  • marcus
  • · Replies 1 ·
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1

Graduate Why does gravity occur?

  • Tyger
  • · Replies 3 ·
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3

Undergrad Which nearby star system should we target for interstellar missions?

  • meteor
  • · Replies 11 ·
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11

Graduate In 1998 Hubble volume meant a cube 12 billion LY on a side

  • marcus
  • · Replies 10 ·
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10

Graduate Early planetary formation thought

  • drag
  • · Replies 1 ·
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1

Graduate Is Photon Energy Lost or Conserved in Cosmological Redshift?

  • (Q)
  • · Replies 25 ·
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25

Graduate What Secrets Do Solar Rings and Shadow Matter Hold?

  • Tyger
  • · Replies 1 ·
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1
  • Poll Poll

Graduate The Hawking wattage of a black hole

  • marcus
  • · Replies 2 ·
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2

Graduate The principle of least action/time, and geodesics of spacetime

  • vshiro
  • · Replies 56 ·
2
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56
  • Poll Poll

Was the first moon landing a fake?

  • Viper
  • · Replies 13 ·
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13

Undergrad What is a Hubble volume?

  • RuroumiKenshin
  • · Replies 8 ·
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8

Graduate Radius of cosmological mass-energy symmetry?

  • Loren Booda
  • · Replies 8 ·
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8

Graduate Can the Infinite Time Theory Be Refuted in Cosmology?

  • Sauwelios
  • · Replies 25 ·
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25

Graduate What happened before the Big Bang?

  • Viper
  • · Replies 33 ·
2
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High School This seems kind of weird, but is there really no such thing as gravity in

  • New-Prototype
  • · Replies 23 ·
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23

Undergrad Photon structure - light decyphering

  • Victor
  • · Replies 8 ·
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8

Undergrad What creates the tail of a comet as it moves through space?

  • charlatan
  • · Replies 1 ·
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1

Graduate A great 16 page paper in quantum cosmology

  • marcus
  • · Replies 1 ·
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1

Graduate Nything beyond the known universe boundaries?

  • Viper
  • · Replies 4 ·
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4

Graduate Dimensionless cosmology-getting rid of units

  • marcus
  • · Replies 8 ·
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8

Undergrad Why isn't the universe shaped like a bubble with a void in the middle?

  • wyzowl
  • · Replies 11 ·
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11

Graduate What is false vacuum and can it collapse from high-energy events?

  • Parsons
  • · Replies 5 ·
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5

Undergrad How is transit time accounted for in universe age estimates?

  • wyzowl
  • · Replies 7 ·
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7

Graduate Is there an anti-space analogous to antimatter?

  • wolram
  • · Replies 6 ·
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6

Graduate Are Refinements to Newton’s Calculations Necessary?

  • Bill Gavlas
  • · Replies 3 ·
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3

Graduate What is the weight of a copy at Earth's average distance from the sun?

  • marcus
  • · Replies 6 ·
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6

Graduate Can the finite space and energy with infinite time theory be refuted?

  • Sauwelios
  • · Replies 9 ·
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9

Graduate Problems with big bang theory expansion and isotropy

  • Michael F. Dmitriyev
  • · Replies 2 ·
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2

Undergrad Is There a Reason for the Unique Shape of This Galaxy?

  • Tyger
  • · Replies 7 ·
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7

Graduate The Physics of Immortality: Fact or Fiction?

  • demiurge
  • · Replies 3 ·
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3

Graduate What does one calorie per cubic mile mean to you?

  • marcus
  • · Replies 4 ·
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4

High School Is Interstellar Travel Feasible with Current Physics?

  • Twisted Angel
  • · Replies 16 ·
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16

Respected Linde vs Far-Out Rees: Who to Follow?

  • Labguy
  • · Replies 1 ·
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1

Graduate What are your ideas about describing Planck units?

  • marcus
  • · Replies 13 ·
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13

Graduate Are black holes regions of absolute zero with no mass or fluctuations?

  • Michael F. Dmitriyev
  • · Replies 4 ·
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4

Einstein was right about the speed of gravity

  • Rashid
  • · Replies 31 ·
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Graduate What experiments confirm the big bang theory?

  • Will
  • · Replies 11 ·
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11

Could the universe be expanding inside a black hole?

  • quasi-quasar
  • · Replies 11 ·
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11

Undergrad S.A.R.S Could this be the result of inbound Particles

  • ranyart
  • · Replies 30 ·
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Graduate Alternative forms of the Friedmann equations

  • marcus
  • · Replies 8 ·
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8
  • Poll Poll

What Happens When Two Black Holes Collide?

  • chosenone
  • · Replies 19 ·
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19

High School Anybody know the name of this mission?

  • enigma
  • · Replies 4 ·
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4

Graduate Could Suicidal Black Holes Evolve Due to Their Charge and Hawking Radiation?

  • MrCaN
  • · Replies 6 ·
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6

Undergrad Does light accelerate when approaching a black hole?

  • Moogle
  • · Replies 7 ·
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7

Graduate If you go fast enough will you turn into a black hole

  • My User Name
  • · Replies 8 ·
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8

Graduate Are there more than two types of charges in spacetime?

  • blike
  • · Replies 20 ·
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Graduate (Not folding space) Instant Travel Form A-B? But Not Time (theory)

  • Stormy
  • · Replies 1 ·
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Graduate Can Inflation Theory Explain the Curious Behavior of Gravity?

  • wimms
  • · Replies 1 ·
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1

Undergrad Where does galactic kinetic energy come from?

  • Saint
  • · Replies 12 ·
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12

Explore the Local Space in 3D: Download Celestia for Free!

  • Mr. Robin Parsons
  • · Replies 2 ·
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2

High School How wide is the Milky Way and how can we see it from inside?

  • Saint
  • · Replies 14 ·
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14

Graduate How quantized space affects graviton transmission in collapsing matter

  • demiurge
  • · Replies 1 ·
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1

Undergrad Why do we skip leap year every 100 years instead of every 25?

  • The_oMeGa
  • · Replies 1 ·
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1

High School How far does the earth travel in one year?

  • wolram
  • · Replies 8 ·
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8

Graduate Why do galaxy clusters form sheets?

  • drag
  • · Replies 5 ·
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5

Graduate Is the Level I Multiverse the Most Popular Cosmological Model Today?

  • MegaFishTank
  • · Replies 8 ·
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8

Graduate Why 1 dimensional discrete space?

  • Eh
  • · Replies 4 ·
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4

Graduate It's Official-The Universe is Absurd

  • wuliheron
  • · Replies 19 ·
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19

Graduate What is the importance of hadronic matter in physics?

  • chaplaintappman22
  • · Replies 2 ·
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2

Undergrad Why does Einstein's Cross show four images instead of a distorted ring?

  • Hydr0matic
  • · Replies 4 ·
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4

Undergrad Finding individual masses of visual binary stars from orbital period

  • pi-70679
  • · Replies 3 ·
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3

Why worry about untestable cosmological speculation

  • MrCaN
  • · Replies 8 ·
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8

Graduate Electrons in intergalactic space.

  • ranyart
  • · Replies 3 ·
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3
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5

Graduate Philosophy of Nature. Time and Space

  • heusdens
  • · Replies 29 ·
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High School Physics of colliding stars for a school project

  • sen_almighty
  • · Replies 3 ·
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3

Graduate IN the Future Blackholes or Wormholes

  • Rashid
  • · Replies 5 ·
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5

Graduate So, Is the gravity of a light emmitting star really decreasing as 1/r?

  • ObsessiveMathsFreak
  • · Replies 20 ·
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20

Graduate Speed of Gravity = c: Does Traveling at C Affect Gravity?

  • wolram
  • · Replies 4 ·
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4

Graduate Do Black Holes and Wormholes Affect Time and Space Similarly?

  • Radiatedtheory18
  • · Replies 3 ·
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3

Is SETI@home worth joining now?

  • KLscilevothma
  • · Replies 18 ·
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18

Graduate Is there a prediction for the frequency of a gravity wave?

  • wolram
  • · Replies 7 ·
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7

Graduate Challenge - A problem in astronomy

  • Messiah
  • · Replies 4 ·
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4

Have you watch the movie the core?

  • Saint
  • · Replies 4 ·
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4

Moving mass good or indifferent?

  • Nowbodylaterenergy
  • · Replies 4 ·
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4

Graduate Is Everything a Form of Positive and Negative Space in Matter?

  • Lifegazer
  • · Replies 13 ·
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13

High School Which Voyager spacecraft traveled further: 1 or 2?

  • Radiatedtheory18
  • · Replies 3 ·
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3

Graduate Skinny galaxy harbors massive black hole at core

  • (Q)
  • · Replies 2 ·
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2

How does light pollution impact birds and other wildlife?

  • Phobos
  • · Replies 16 ·
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16

Graduate A universe with no beginning or end

  • Eh
  • · Replies 114 ·
4
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114

Graduate Black hole event horizon as surface of spacetime symmetry

  • Loren Booda
  • · Replies 2 ·
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2

High School Is There a Giant Black Hole at the Centre of the Universe?

  • Viper
  • · Replies 58 ·
2
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58

Graduate Do rivers and whirlpools of spacetime exist with superluminal flow?

  • Loren Booda
  • · Replies 4 ·
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4

Jupiter is up to 58 moons (more likely)

  • Phobos
  • · Replies 14 ·
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14

Graduate Why does matter in solar systems settle into a flat plane?

  • Njorl
  • · Replies 9 ·
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9

High School 200,000 years for 1mg of antimatter?

  • galoku
  • · Replies 4 ·
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4

High School Europa and the possibilty of habitibility

  • Rashid
  • · Replies 11 ·
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11

Graduate Does dark energy acceleration lead to a cyclic universe?

  • GENIERE
  • · Replies 19 ·
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19

Graduate Why does light change wavelength without an ether to carry it?

  • O Great One
  • · Replies 8 ·
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8

Graduate Is There Hope for Safe Passage Through Cauchy Horizon Singularities?

  • Brad_Ad23
  • · Replies 2 ·
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2

Midwesterners take a meteorite shower

  • Phobos
  • · Replies 4 ·
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4
  • Poll Poll

High School When will we have a Mars Landing?

  • Jack
  • · Replies 10 ·
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10

Graduate Magnetic Fields of Neutron Stars

  • Nebula
  • · Replies 6 ·
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6

Graduate Was the formation of our galaxy inevitable

  • wolram
  • · Replies 24 ·
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24

Graduate What exactly will happen if the big rip occurs

  • Jack
  • · Replies 1 ·
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1

Graduate New Hubble Measurements Challenge Physicists: Space May be Smooth

  • Chagur
  • · Replies 3 ·
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3