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

Calculate the Gravity of a Black Hole

  • ZavraD
  • · Replies 6 ·
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6

Graduate Orbit Dynamics in an Expanding Universe

  • Buzz Bloom
  • · Replies 17 ·
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17

High School Can Black Holes Really Die and What Are Their Secrets?

  • Kenneth Korsmo
  • · Replies 76 ·
3
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76

Undergrad How was Galileo able to observe Venus's phases?

  • TheExibo
  • · Replies 6 ·
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6

High School How Are Black Holes Formed and What Are Their Key Facts?

  • haileyparikh
  • · Replies 34 ·
2
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34

High School Where Do Wormholes Take Us in Space and Time?

  • astrophysicskid
  • · Replies 1 ·
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1

Graduate Can a See Saw Extend from Earth to Another Galaxy?

  • PhysicsFan11
  • · Replies 25 ·
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25

What Would a Trip from Earth to Orion Look Like?

  • tony873004
  • · Replies 1 ·
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1

Graduate Origins of the Fundamental Interactions/Forces

  • HeavyWater
  • · Replies 3 ·
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3

Nice ongoing planetary alignment

  • Bandersnatch
  • · Replies 1 ·
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1

Undergrad Juno Flyby Anomaly - Searching for Answers

  • nearc
  • · Replies 8 ·
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8

Undergrad Infinite Universe: Can It Ever End?

  • Einstein's Cat
  • · Replies 6 ·
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6

Graduate How can light have momentum if it has zero mass?

  • bcrowell
  • · Replies 6 ·
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6

Graduate Is a Magnetic Levitation Space Launcher Possible?

  • msinclairinork
  • · Replies 11 ·
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11

Graduate Is Multiverse proven by Plank data?

  • Alexis1304
  • · Replies 4 ·
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4

Graduate Metric expansion misunderstanding

  • Lanniakea
  • · Replies 13 ·
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13

High School Is this a photograph of water on Mars?

  • newjerseyrunner
  • · Replies 1 ·
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1

Graduate Is the Universe's Expansion Actually Slowing Down?

  • jssamp
  • · Replies 6 ·
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6

Graduate MOND and the missing baryons problem

  • wolram
  • · Replies 41 ·
2
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41

High School What are the ways we can search for alien life?

  • @PK nd
  • · Replies 62 ·
3
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62

Graduate No Dark Matter or gravity modification for flat rot

  • wolram
  • · Replies 5 ·
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5

High School Explore the Solar System with a Dynamic Simulator for Teaching - Free Download

  • AHashemi
  • · Replies 2 ·
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2

Proper motion of Ursa Major (Big Dipper)

  • tony873004
  • · Replies 2 ·
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2

Graduate Gravitational lensing as a way of observing Milky Way?

  • SheriffPeabody
  • · Replies 6 ·
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6

Graduate The Inflaton Field And Repulsive Gravity

  • BOAS
  • · Replies 13 ·
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13

High School Move Mass in Space: How Much Pull?

  • marmstrong941
  • · Replies 26 ·
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26

Graduate Expansion then Contraction....an infinite Elastic Collision?

  • halpmaine
  • · Replies 9 ·
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9

Graduate Saturn: Helium Rain, or non-indigenous planet?

  • JDoolin
  • · Replies 6 ·
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6

High School What Are the Physical Limitations of a Dyson Sphere?

  • Justice Hunter
  • · Replies 5 ·
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5

Graduate Time, Mass & Space: Does Time Stay Consistent?

  • pnorris2000
  • · Replies 2 ·
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2

Graduate Heliocentric polar orbit crossing the Earth's orbit twice

  • xpell
  • · Replies 8 ·
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8

Graduate Is the universe fine tuned for life

  • wolram
  • · Replies 21 ·
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21

Graduate Collision of massive star with black hole

  • Johninch
  • · Replies 13 ·
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13

Undergrad Kepler's 2nd across a system of planets

  • tfr000
  • · Replies 4 ·
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4

High School Suggest a Quantum Physics Book for a 16 Year Old

  • ayush solanki
  • · Replies 6 ·
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6

Graduate Question re Galaxy Rotation Curve

  • Buzz Bloom
  • · Replies 3 ·
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3

Graduate Mass of a Black Hole: Answers & Questions

  • Nemika
  • · Replies 8 ·
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8

Graduate Likelihood of confirming past life on Mars

  • dilletante
  • · Replies 6 ·
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6

Undergrad Cosmology looks beyond the standard model

  • wolram
  • · Replies 3 ·
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3

High School Venus Info: Is It Hot & How to Cool It Down?

  • marmstrong941
  • · Replies 3 ·
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3

Graduate Consequences of Overlapping Event Horizons in Supermassive Black Hole Mergers

  • FredrikJ
  • · Replies 4 ·
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4

Graduate What happens to matter when it enters a black hole?

  • RealTwistedTwin
  • · Replies 12 ·
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12

Is the Celestron Omni XLT 120 Refractor Telescope worth the investment?

  • DaveC426913
  • · Replies 7 ·
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7

Undergrad Calculating Universe Density: Cosmology Equations

  • AleksanderPhy
  • · Replies 7 ·
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7

Graduate Can Neutrons Emit Light Without Electrons to Swoosh Them Away?

  • Low-Q
  • · Replies 22 ·
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22

Graduate The Universe Never Expands Faster than the Speed of Light

  • Chalnoth
  • · Replies 11 ·
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11

Undergrad At what speed is our universe expanding?

  • Shafat Hasan
  • · Replies 18 ·
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18

Undergrad Does an Expanding Universe Alter How Quickly Light Travels Through Space?

  • Gal
  • · Replies 2 ·
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2

Graduate Will a bouncing cosmology lose information

  • wolram
  • · Replies 12 ·
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12

Graduate Why Does Increased Baryon Loading Shift Power Spectrum to Higher Multipoles?

  • gluon
  • · Replies 1 ·
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1

Graduate What Happens to Electrons in Synchrotron Radiation?

  • shirin
  • · Replies 2 ·
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2

Graduate Are Atoms Just Empty Space If Fundamental Particles Are Zero-Dimensional?

  • Nav
  • · Replies 12 ·
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12

Graduate Alternative Theories: Ghirardi-Rimini-Weber and the Many Worlds Interpretation

  • slatts
  • · Replies 7 ·
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7

Graduate What Is the Impact of Shape on Escape Velocity in an Expanding Universe?

  • Buzz Bloom
  • · Replies 8 ·
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8

Graduate Why should the Bullet Cluster focus light?

  • Earnest Guest
  • · Replies 35 ·
2
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35

Undergrad Understanding Observing Frequency and Its Significance in Radio Astronomy

  • shirin
  • · Replies 5 ·
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5

Stargazing What are the upper physical resolution limits on telescopes?

  • BWV
  • · Replies 7 ·
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7

Graduate Comparing Radio and X-Ray Galaxies: Redshift vs. Emission Mechanism

  • shirin
  • · Replies 6 ·
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6

Graduate First detection of direct collapse black holes?

  • Chronos
  • · Replies 2 ·
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2

Graduate Possible to derive an approximation of G from a Saros ?

  • Isaacsname
  • · Replies 2 ·
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2

High School Could Life Exist on Mars with the Discovery of Flowing Water?

  • @PK nd
  • · Replies 6 ·
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6

Undergrad Does the black matter has weight?

  • Nemika
  • · Replies 1 ·
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1

Graduate Solving Freidmann Equation: Understand Calculations & Cosmology

  • AleksanderPhy
  • · Replies 4 ·
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4

Graduate What can the Anthropic Principal predict?

  • Buzz Bloom
  • · Replies 2 ·
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2

Graduate Event Horizons = Cosmological Horizons?

  • Salamon
  • · Replies 19 ·
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19

Graduate Confusion re Laniakea Super Cluster

  • Buzz Bloom
  • · Replies 1 ·
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1

Undergrad Dependence of rotational angular velocity of planets

  • Abhirikshma
  • · Replies 2 ·
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2

Graduate What is the purpose of the Einstein stress-energy tensor?

  • AleksanderPhy
  • · Replies 1 ·
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1

Undergrad Why are photons affected by gravity?

  • ayush solanki
  • · Replies 8 ·
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8

Undergrad About doubling the mass of the planets and the sun of our solar system

  • ayush solanki
  • · Replies 10 ·
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10

Graduate How Does Synchrotron Radiation Influence Observations in Radio Astronomy?

  • shirin
  • · Replies 2 ·
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2

Graduate Radiation from the surface of a star

  • jorgeavg
  • · Replies 6 ·
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6

Graduate Gas Mass Calcuation in Galaxy Cluster

  • Earnest Guest
  • · Replies 3 ·
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3

Stargazing Why Aren't There Telescopes on the Moon?

  • Gerinski
  • · Replies 115 ·
4
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115

Graduate Spaghettification and gravity in theory of relativity?

  • Pejeu
  • · Replies 1 ·
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1

Graduate Are Interstellar Extinction Variations Misleading Cosmological Measurements?

  • wolram
  • · Replies 1 ·
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1

Graduate Time at the big bang and in very early time after that

  • Prins
  • · Replies 2 ·
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2

Graduate Population 1 vs Population 2 Stars: Metal Rich vs Metal Poor

  • Shivansh Mathur
  • · Replies 1 ·
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1

Graduate Is the X-Ray Mass of the Coma Cluster Accurately Measured?

  • Earnest Guest
  • · Replies 2 ·
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2

George Will endorses space research

  • gleem
  • · Replies 1 ·
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1

Graduate Random Walk Question re Inflation

  • Buzz Bloom
  • · Replies 8 ·
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8

Graduate Does the Bullet Cluster Disprove MOND and Challenge ΛCDM?

  • Earnest Guest
  • · Replies 41 ·
2
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41

Graduate Origin of Quantum Perturbations?

  • slatts
  • · Replies 15 ·
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15

Graduate Good 1st year grad level texts in galaxies and cosmology

  • CosmicDestiny
  • · Replies 1 ·
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1

Graduate How Does the CMB Frame Differ from Other Frames in Relativity?

  • palmer eldtrich
  • · Replies 8 ·
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8

High School I've heard gravity can "fling" stuff, how does this work?

  • Coolamebe
  • · Replies 6 ·
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6

Graduate Computing osculating orbital elements

  • cptolemy
  • · Replies 4 ·
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4

Graduate How many hypothetical particles do we need

  • wolram
  • · Replies 5 ·
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5

Undergrad Why can dark matter make our planets move in same velocity?

  • Space Dragon
  • · Replies 11 ·
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11

Graduate Fine tuning, muitverse and a double standard

  • palmer eldtrich
  • · Replies 10 ·
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10

Graduate How does gravity get out of a black hole?

  • nburns
  • · Replies 4 ·
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4

Graduate Destruction of Solar System by passing Star

  • Hornbein
  • · Replies 14 ·
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14

Graduate What is the evidence for dark matter in the solar neighborhood?

  • wolram
  • · Replies 7 ·
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7

Graduate How Do Scientists Determine the Composition of a Star's Core?

  • Jimmy87
  • · Replies 3 ·
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3

Graduate Do Galaxy Clusters follow De Vaucouleurs' Law?

  • Earnest Guest
  • · Replies 3 ·
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3

Graduate Why don't all neutron stars collapse into black holes?

  • dect117
  • · Replies 23 ·
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23

Graduate Distinction between special and general relativity

  • bcrowell
  • · Replies 51 ·
2
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51

High School Sun & Horizon: Why Does it Look Different?

  • avito009
  • · Replies 1 ·
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1

Graduate Re Dark Matter and the Horizon Problem

  • Buzz Bloom
  • · Replies 3 ·
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3

Graduate What Causes the Higher Peaks and Damping Tail in the CMB Power Spectrum?

  • gluon
  • · Replies 4 ·
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4