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 Negative Acceleration in Black Holes

  • humuus
  • · Replies 4 ·
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4

Graduate The fuzzball proposal for black holes

  • wolram
  • · Replies 1 ·
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1

Graduate Visualizations without space-time or light

  • wawens
  • · Replies 35 ·
2
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35

Graduate Angular momentum of an oblate spheroid

  • stevebd1
  • · Replies 4 ·
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4

Graduate Hawking radiation & Information loss

  • spidey
  • · Replies 5 ·
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5

Graduate Beckenstein Bound: Understanding Smolin's Entropy Bounds

  • Coin
  • · Replies 4 ·
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4

High School A question about the evidence for the age of our known universe

  • jfrancis
  • · Replies 7 ·
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7

Graduate Has anyone rebutted E. Lester Smith's Intelligence Came First theory?

  • asterias
  • · Replies 3 ·
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3

Graduate At the April APS meeting: curing cosmic singularities

  • marcus
  • · Replies 1 ·
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1

Undergrad What Are the Key Insights into Dark Energy for Cosmology Students?

  • Jared37
  • · Replies 6 ·
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6

Graduate Rotational kinetic energy and gravity

  • stevebd1
  • · Replies 3 ·
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3

Graduate How Do Black Hole Masses Compare to Normal Matter in the Universe?

  • CosmiCarl
  • · Replies 5 ·
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5

Undergrad What Keeps the Galaxy Intact?

  • Peralta_Man
  • · Replies 4 ·
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4

Largest Known Star: Introducing Myself and Cosmology

  • Star-Gazer
  • · Replies 3 ·
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3

Graduate Who the top quantum cosmology researchers are

  • marcus
  • · Replies 34 ·
2
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34

Graduate Titius-Bode law, any analytical or numerical derivation?

  • Ulysees
  • · Replies 14 ·
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14

Graduate Relativity or Relativistic Theromdynamics

  • hagopbul
  • · Replies 4 ·
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4

Graduate How Does Solid Hydrogen Impact Our Understanding of Cosmology?

  • jal
  • · Replies 5 ·
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5

Undergrad Human versus robotic spaceflight

  • D H
  • · Replies 46 ·
2
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46

Graduate What Is the Orbital Period of an Asteroid with a Temperature of 200 K?

  • rodrigues
  • · Replies 4 ·
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4

Graduate Discovering the Solar Corona Luminosity Curve: Explained and Explored

  • Eleftheria
  • · Replies 2 ·
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2

Undergrad Universe burnout-What's so hard about that

  • Capernicus
  • · Replies 17 ·
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17

High School Thank you for your understanding.Dr. Gregory GreenmanPhysicist

  • sudhirking
  • · Replies 11 ·
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11

Graduate Escaping the Impending Heat Death of the Universe: A Possibility or a Fantasy?

  • hammertime
  • · Replies 3 ·
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3

Graduate Is There a Contradiction Between Entropy in Thermodynamics and Cosmology?

  • josephpalazzo
  • · Replies 8 ·
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8

Just one irrefutable datum point

  • wolram
  • · Replies 1 ·
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1

Graduate What Lies Beyond Our Universe? Physicists' Opinions

  • lionell
  • · Replies 2 ·
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2

Graduate Universe doesn't equal Time travel

  • runicle
  • · Replies 5 ·
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5

Undergrad What would happen to Earth without the moon?

  • Ulysees
  • · Replies 12 ·
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12

High School Why Don't We Feel Earth's Movement and How Do Tides Affect Well Water Levels?

  • mnhtapu
  • · Replies 13 ·
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13

Undergrad Gamma Ray burst in the Milkey Way

  • talmans
  • · Replies 12 ·
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12

High School Rockets in Space: Need for Engines to Change Direction

  • Ry122
  • · Replies 7 ·
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7

Graduate Snowplow model of a supernova remnant

  • Tuugii
  • · Replies 4 ·
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4

High School Moon without Earth: What if Earth Disappears?

  • Timoothy
  • · Replies 14 ·
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14

High School Demonstrating Moon's Lack of Internal Rotation

  • Timoothy
  • · Replies 10 ·
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10

Graduate Universal quality of virial theorem

  • giann_tee
  • · Replies 1 ·
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1

High School Finding a Local Star Like Ours: 10-50 LY Radius

  • MDW
  • · Replies 1 ·
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1

Undergrad Cosmology getting stale with discoveries?

  • Chaos' lil bro Order
  • · Replies 8 ·
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8

High School Sun's Energy Output: How Much & What Could it Power?

  • Holocene
  • · Replies 5 ·
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5

Undergrad Why is the Earth getting closer to the sun and the moon getting farther away?

  • DM
  • · Replies 5 ·
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5

Undergrad Naked-Eye Visible GRB: Witnessing Halfway Across All Creation

  • DaveC426913
  • · Replies 5 ·
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5

Undergrad Why don’t planet hunters find black holes?

  • jimgraber
  • · Replies 2 ·
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2

High School Why do we see the near side of the moon only?

  • anonymoussome
  • · Replies 23 ·
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23

Graduate Urban legends in authoritative astronomy

  • Ken G
  • · Replies 46 ·
2
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46

High School Earth's Closest Approach to the Sun: Does the Date Change?

  • Ulysees
  • · Replies 4 ·
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4

Graduate Can Early Dark Energy Affect Standard Rulers in Cosmology?

  • wolram
  • · Replies 1 ·
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1

What are the limiting factors in this case

  • mubashirmansoor
  • · Replies 4 ·
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4

Undergrad Why Does Earth's Axis Precess Like a Spinning Top?

  • Ulysees
  • · Replies 3 ·
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3

Graduate Is the Entropy of Black Holes Measurable for Non-Exotic Black Holes?

  • RasslinGod
  • · Replies 6 ·
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6

Graduate Good textbooks on modern cosmology ?

  • smallphi
  • · Replies 6 ·
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6

Graduate How Do Interpretations of Hubble Expansion Differ Empirically?

  • my_wan
  • · Replies 5 ·
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5

Graduate Minimum value of g for blackhole

  • spidey
  • · Replies 1 ·
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1

Undergrad Light Entering Black Hole: Observed or Not?

  • spidey
  • · Replies 5 ·
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5

Have You Read Weinberg's Cosmology Yet?

  • superpoincare
  • · Replies 9 ·
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9

Undergrad How Are Black Holes Detected and Measured?

  • shaan_aragorn
  • · Replies 11 ·
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11

Alternative idea on expanding universe

  • W3pcq
  • · Replies 12 ·
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12

Undergrad Dark Matter & Universe Expansion: A Newbie Question

  • viridian
  • · Replies 7 ·
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7

Undergrad Relation between earth position in orbit and its tilt

  • pixel01
  • · Replies 5 ·
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5

Graduate Is There a Universal Point Where All Moments in Time Exist Simultaneously?

  • zengin
  • · Replies 4 ·
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4

Graduate Possible webpage title: Need Help with These Astronomy Questions?

  • SilverHammer
  • · Replies 1 ·
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1

High School Newbie question on atsrophotography

  • Holocene
  • · Replies 2 ·
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2

Graduate Is the Secret Number to the Universe 10^122?

  • SF
  • · Replies 16 ·
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16

High School A Beginner's Guide to Learning About Black Holes

  • Owen-
  • · Replies 9 ·
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9

Graduate Estim. dark energy up by 3 percentage points. Any reaction?

  • marcus
  • · Replies 3 ·
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3

Graduate Gravity for a stellar black hole

  • stevebd1
  • · Replies 26 ·
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26

Undergrad Can two stars have the same apparent but different absolute magnitudes

  • bse
  • · Replies 6 ·
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6

Graduate Superbubbles from shock waves from supernova or stellar winds?

  • sarahrose
  • · Replies 2 ·
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2

Undergrad Earth/solar position vs spiral arms

  • ray b
  • · Replies 3 ·
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3

Graduate Meaning of setting the scale factor equal to 1 at present epoch

  • kdv
  • · Replies 3 ·
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3

High School Moon Preservation: What if a Spaceshuttle or Missile Hit It?

  • h.g.Whiz
  • · Replies 5 ·
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5

In the Beginning: How Many Object to Creation-Like Events?

  • Chronos
  • · Replies 9 ·
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9

Undergrad What Material Makes Up Black Holes?

  • pixel01
  • · Replies 6 ·
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6

Astronomy Videos: Collection by NGC6822 on YouTube

  • drosser
  • · Replies 1 ·
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1

Anybody know anything about parallelogram mounts

  • Saladsamurai
  • · Replies 6 ·
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6

Undergrad . Radio Spectroscopy -> Finding the doppler shift in a graph

  • PhysicsHelp12
  • · Replies 1 ·
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1

Graduate Question from a fool about the big bang

  • zengin
  • · Replies 13 ·
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13

Undergrad Just a simple explanation please

  • hedkrash
  • · Replies 5 ·
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5

Graduate Tired light vs. expanding universe

  • ntdg634
  • · Replies 2 ·
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2

Undergrad Equatorial Bulge: Causes & Explanation

  • Sheneron
  • · Replies 10 ·
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10

Graduate Is Cosmological Inflation the reason for the uniformity of the universe?

  • Dav333
  • · Replies 8 ·
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8

Graduate Massless Universe: Examining the Behaviour & Mass of Our Universe

  • Xbehave
  • · Replies 8 ·
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8

Graduate A question regarding the orbit of material in a galaxy such as ours

  • shalayka
  • · Replies 2 ·
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2

Undergrad Can two planets inhabit the same orbit?

  • astro1000000
  • · Replies 4 ·
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4

An astrophysicist (+blogger) to be aware of

  • marcus
  • · Replies 0 ·
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0

Undergrad Just Checking - Calculating Angular Diameter of Moon

  • TFM
  • · Replies 2 ·
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2

Graduate Can there be anything outside of our Existance?

  • Blahness
  • · Replies 15 ·
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15

Graduate Measuring the temperature of quasars

  • Frank Lampard
  • · Replies 2 ·
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2

Undergrad Calculating Absolute Magnitude of a Star - Red's Help

  • redbaldyhead
  • · Replies 1 ·
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1

Graduate Could Dark Matter be mass in EM fields?

  • warwickphys
  • · Replies 7 ·
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7

Solve Your HR Diagram Problem with Expert Help - Tuugii

  • Tuugii
  • · Replies 3 ·
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3

Graduate Dark Energy and the Accelerating Universe (survey)

  • marcus
  • · Replies 2 ·
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2

Undergrad Advantage of measuring stellar parallaxes from Mars rather than Earth?

  • bse
  • · Replies 2 ·
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2

Graduate Dark Matter Pooling: Gravitational Effects Explained

  • nesp
  • · Replies 11 ·
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11

Graduate Acceptable cosmological discussions

  • CBC
  • · Replies 4 ·
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4

Support Space Exploration: Agree or Not?

  • wolram
  • · Replies 1 ·
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1

Graduate If blackholes, then antiblackholes?

  • pseudo
  • · Replies 2 ·
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2

How do i find a Astronomy club close to me ?

  • mouse23432
  • · Replies 2 ·
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2

Undergrad Is the Universe Spinning After the Big Bang?

  • Hool
  • · Replies 1 ·
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1

Undergrad Satellite Right Acension and Declination Calculations

  • isi
  • · Replies 4 ·
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4

Undergrad Are matter and energy equally represented

  • crazylum
  • · Replies 2 ·
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2