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 Loop bounce and geometric entropy (re: Bill A's question)

  • marcus
  • · Replies 6 ·
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6

Undergrad Does the Universe Have a Center of Mass and Why Is It Expanding?

  • kahwawashay1
  • · Replies 26 ·
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26

Undergrad How is the degree of vacuum in the Universe measured?

  • Yuri B.
  • · Replies 4 ·
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4

Graduate Using Black holes to view our solar system

  • elegysix
  • · Replies 1 ·
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1

Graduate Is there any way how to dispove that universe is a computer simulation?

  • No-where-man
  • · Replies 12 ·
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12

Undergrad Understanding Very Long Baseline Interferometry: Is the Formula the Same as #2?

  • s3a
  • · Replies 6 ·
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6

Graduate Is the Energy of the Universe Really Zero?

  • da_willem
  • · Replies 20 ·
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20

Graduate Increasing the mass of the moon (via pancake theory)

  • Princedragon
  • · Replies 5 ·
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5

Graduate What Causes Early Convective Instabilities in Supernova Explosions?

  • Chronos
  • · Replies 11 ·
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11

Stargazing Why are Radio Telescopes less detailed?

  • Vorde
  • · Replies 5 ·
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5

Stargazing Telescope for my astronomy class next semester

  • HeLiXe
  • · Replies 2 ·
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2

Graduate Hubble constant depend on expansion model?

  • johne1618
  • · Replies 3 ·
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3

Graduate Expanding Space: Explaining the Mystery

  • cragar
  • · Replies 4 ·
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4

Graduate Are the Outer Bands of Galaxies Moving Faster Than the Speed of Light?

  • DaddyJax
  • · Replies 10 ·
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10

Undergrad Our solar system and center of Milky way

  • ahmediukas
  • · Replies 7 ·
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7

Graduate Failure to calculate equation of time and declination of the sun

  • dwaynie
  • · Replies 4 ·
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4

Undergrad The Universe: A Mobius Strip of Possibilities?

  • infinitea
  • · Replies 2 ·
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2

Graduate No Obvious Objects Produce Gamma Rays

  • Dotini
  • · Replies 3 ·
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3

Undergrad Need a good textbook for astrophysics

  • achuthan1988
  • · Replies 1 ·
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1

Undergrad Is Hubble Constant Really Constant?

  • jayaramas
  • · Replies 5 ·
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5

Graduate Those Jets from the poles of black holes

  • Daniel Batt
  • · Replies 9 ·
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9

Undergrad Newtons of an exploding Supernova

  • Physics quest
  • · Replies 14 ·
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14

Graduate Need Help Settling a Debate About Guns in Space

  • scorpiooooooh
  • · Replies 8 ·
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8

Undergrad Could an all water planet theorhetically exist?

  • larrybud
  • · Replies 20 ·
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20

Have I seen the layers of parallel universes.

  • datacloud
  • · Replies 14 ·
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14

Graduate Could a star survive a direct hit from a gamma ray burst?

  • Astroboy123
  • · Replies 13 ·
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13

Graduate Space-time created ahead of matter - how far?

  • Saddlestone
  • · Replies 37 ·
2
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37

Graduate Why Even Talk About Gravitons Even Existing?

  • NYSportsguy
  • · Replies 43 ·
2
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43

Undergrad Converting RA & Dec into Normal Earth Surface Latitude & Longitude

  • Gannet
  • · Replies 14 ·
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14

Graduate Nature of Dark Energy and a cracker in the sand

  • Hammer76
  • · Replies 21 ·
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21

High School Queen's song '39 - the only pop song about relativity?

  • Saddlestone
  • · Replies 3 ·
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3

Graduate How do black holes radiate if nothing can escape?

  • 2sin54
  • · Replies 4 ·
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4

Graduate Need help understanding U.S. Naval Observatory's messed up algorithm

  • dwaynie
  • · Replies 7 ·
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7

Undergrad Why Does Lithium Stay on the Surface of the Sun?

  • sawtooth500
  • · Replies 4 ·
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4

Graduate Understanding the Universe: Explaining Light Speed and Expansion

  • Ut-Napishtim
  • · Replies 10 ·
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10

Graduate Average value of sin(i) in radial velocities (exoplanets)

  • cahill8
  • · Replies 1 ·
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1

Undergrad Force that the Earth exerts on the Moon

  • Poppinkrey
  • · Replies 7 ·
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7

Graduate What are Cosmic Rays and How Can They Help Us Understand the Universe?

  • Cluelessluke
  • · Replies 1 ·
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1

Graduate Reevaluating the Big Bang Theory: Challenging the 13.7 Billion Light Year Limit

  • shashankac655
  • · Replies 26 ·
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26

I'm writing a novel involving worm holes and asteroids/meteors

  • Haendelrsz
  • · Replies 3 ·
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3

Graduate How realistic is a time compression vacation destination with a high rate?

  • nemorosa
  • · Replies 11 ·
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11

Graduate Conflict between reionization and the most distant object

  • thenewmans
  • · Replies 6 ·
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6

Graduate Can Laser-Pushed Solar Sails Achieve Near Light Speed by Circling Back?

  • udtsith
  • · Replies 9 ·
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9

High School What is a parallel universe and how does it relate to physics?

  • VaibhavP
  • · Replies 5 ·
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5

Graduate Acceleration of two bodies in circular orbit provided by own gravity

  • Ry122
  • · Replies 2 ·
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2

Graduate Why the early universe didn't collapse into a black hole?

  • shazdeh
  • · Replies 18 ·
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18

Graduate State Space Analyis - the 'B' matrix

  • phiby
  • · Replies 2 ·
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2

Undergrad Could Protons and Electrons Explain the Big Bang's Origins?

  • aherrera
  • · Replies 7 ·
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7

Graduate Calculation of a planet's mass via wavelengths

  • Poppinkrey
  • · Replies 2 ·
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2

Undergrad Effects of dark energy on our solar system

  • VaibhavP
  • · Replies 6 ·
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6

Graduate Unveiling the Mystery of Antimatter Galaxies: Modern Cosmology's Perspective"

  • Delta2
  • · Replies 5 ·
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5

Graduate Universe's full cycle: explosion - implosion

  • Yuri B.
  • · Replies 1 ·
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1

Stargazing Spectra Optics telescope 1400X150 questions

  • Gliese123
  • · Replies 23 ·
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23

Graduate Comparing Sidereal & Synodic Reference Frames

  • Ry122
  • · Replies 1 ·
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1

Graduate Proof of Red Shift that indicates Expansion

  • Buckeye
  • · Replies 26 ·
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26

Graduate Electro-Gravity ideas, Dark Energy

  • happienumber
  • · Replies 7 ·
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7

Graduate Surprising Gamma Rays From Crab Nebula

  • Dotini
  • · Replies 4 ·
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4

Graduate Do all pulsars have a Pulsar wind nebula?

  • StephanJ
  • · Replies 1 ·
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1

Graduate What percentage of solar energy is converted to solar neutrinos?

  • jayaramas
  • · Replies 2 ·
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2

Graduate Cyclic Universe - Fixed in Size but Divided into 8 Sections

  • Buckeye
  • · Replies 7 ·
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7

Undergrad How do neutrinos behave near a black hole?

  • jayaramas
  • · Replies 5 ·
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5

Graduate How many dimensions compose reality?

  • Duhoc
  • · Replies 15 ·
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15

Graduate Dark matter or variable gravity?

  • slooper2112
  • · Replies 13 ·
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13

Graduate Arp 220 (UGC 9913, IC 4553) and Supernovae

  • Astronuc
  • · Replies 1 ·
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1

Graduate General relativity: a poor description of spacetime

  • skylark53
  • · Replies 10 ·
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10

Graduate Converting spectrum into velocity space

  • Piano man
  • · Replies 5 ·
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5

Graduate Explanation for gravity and mass?

  • IvorGeorge
  • · Replies 1 ·
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1

Graduate How Does Earth's Helical Trajectory Affect Its Calculated Speed Through Space?

  • TrickyDicky
  • · Replies 6 ·
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6

Undergrad Any difference between type 1a supernovae and a novae

  • srikar97
  • · Replies 8 ·
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8

Undergrad Should space exploration be only the developed world’s adventure?

  • shashankac655
  • · Replies 113 ·
4
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113

Undergrad What are the requirements for interstellar travel at different speeds?

  • Jon0815
  • · Replies 4 ·
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4

Graduate What Are the Flaws in Stenger's Argument on the Origins of Order?

  • bobsmith76
  • · Replies 3 ·
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3

Graduate Can Regular Matter and Dark Matter Be the Same Thing in Higher Dimensions?

  • raid1000
  • · Replies 1 ·
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1

Graduate How do I measure the distance of a galaxy using conventional terms?

  • Skolon
  • · Replies 8 ·
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8

High School Sun Angle: Differences by Season

  • DaveC426913
  • · Replies 14 ·
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14

Graduate Greatest cosmic energy detected by Veritas

  • TrickyDicky
  • · Replies 1 ·
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1

Graduate What is the Geometry of Spacetime Near the Big Bang?

  • Imax
  • · Replies 17 ·
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17

Graduate How Can I Use the Two-Point Correlation Function to Compare Image Structures?

  • mikeph
  • · Replies 6 ·
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6

Graduate What Causes the Sinusoidal Waviness in UARS Orbital Altitudes?

  • jna
  • · Replies 15 ·
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15

Undergrad Planet Hunters: First Two Planet Candidates Identified

  • Drakkith
  • · Replies 2 ·
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2

Graduate Unraveling the Mystery of Total Energy in the Universe

  • Curious6
  • · Replies 28 ·
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28

Undergrad What is the relationship between dark matter and gravity?

  • confused????
  • · Replies 25 ·
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25

Graduate Black Hole Radiation: Types, Perfect Blackbody & Collapsing Bodies

  • khil_phys
  • · Replies 26 ·
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26

Undergrad How Does Mass Affect Stellar Luminosity and Simulations?

  • jdlawlis
  • · Replies 17 ·
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17

Graduate Found Another (Astrophysical) Error in Science Television

  • BadBrain
  • · Replies 13 ·
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13

Undergrad If center of galaxy is supermassive blackhole

  • Chitose
  • · Replies 28 ·
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28

Undergrad Is gravity a weak force compared to other forces in the universe?

  • GRAViL59
  • · Replies 17 ·
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17

Graduate Wasn't the universe more disordered in the past?

  • zeromodz
  • · Replies 4 ·
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4

Graduate Info on the supernova accelerating space Nobel prize.

  • Agerhell
  • · Replies 2 ·
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2

Graduate What are the limits of redshift?

  • Lost in Space
  • · Replies 9 ·
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9

Graduate Photons vs neutrinos energy ratio

  • Calimero
  • · Replies 4 ·
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4

High School How do measure and know about the vast scale of the Universe?

  • kyler.e
  • · Replies 6 ·
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6

Undergrad Help me to get the names of all stars with their declination?

  • purnendu.007
  • · Replies 3 ·
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3

Graduate Creating a Sci-Fi World - Thea (Questions & Answers)

  • MattRob
  • · Replies 11 ·
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11

Undergrad What is the centroid of the earth-moon system and how is it calculated?

  • Ry122
  • · Replies 4 ·
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4

Graduate Is it practically possible to look back in time?

  • Sobadzhiev
  • · Replies 11 ·
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11

Graduate How does a very long object in space act with time

  • d3nd3
  • · Replies 7 ·
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7

Graduate There is more meaning in the universe than there is matter

  • treehouse
  • · Replies 1 ·
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1

Graduate Questions on Neutrinos: Mass, OPERA & More

  • AlfreCabo
  • · Replies 5 ·
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5

Graduate Accurate distance gauge out to z ~ 4 alleged (AGN)

  • marcus
  • · Replies 3 ·
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3