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 Black Holes May Contain Tiny Universe - Nariai Universes

  • hammertime
  • · Replies 8 ·
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8

Undergrad How do you measure black hole mass differently than planet mass?

  • Eternalmetal
  • · Replies 14 ·
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14

Graduate Complete Hill Sphere Derivation: Learn the Equation and its Derivation Process

  • Tefeari
  • · Replies 5 ·
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5

Graduate Does satellite mass affect the Hill sphere formula?

  • Fennelgiraffe
  • · Replies 7 ·
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7

High School How can I write a 5 page paper on the origin of the solar system?

  • SolarSystHelp
  • · Replies 2 ·
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2

Identifying Objects in the Solar System

  • ElizebethDylan
  • · Replies 15 ·
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15

Graduate How big can a body get (size wize) before it collapses onto itslef?

  • rubecuber
  • · Replies 11 ·
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11

Graduate Would a black hole create a wormhole in space?

  • cooldude3122
  • · Replies 5 ·
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5

Graduate Finding AGB Star Phases: Modeling S-Process in a Helium Shell Burning Region

  • malawi_glenn
  • · Replies 2 ·
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2

Graduate What Lies Beyond the Edge of the Universe?

  • ColdFusion85
  • · Replies 36 ·
2
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36

Graduate What Happened to the Energy from Matter/Anti-Matter Annihilation?

  • phetuspolice
  • · Replies 1 ·
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1

Is There Real Evidence for the Moon Landing?

  • davidschmid10
  • · Replies 3 ·
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3

High School Layperson books on space, time, dimensions and quantum gravity

  • squidley
  • · Replies 8 ·
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8

Graduate Is the Evidence for Dark Energy Secure?

  • cristo
  • · Replies 5 ·
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5

Undergrad Online planetarium site for identifying stars at your location

  • Art
  • · Replies 3 ·
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3

Undergrad Calculating Circumpolar Star Declination for Different Latitudes

  • shaheen
  • · Replies 3 ·
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3

High School Can we see stars from other galaxies with the naked eye?

  • onemind
  • · Replies 6 ·
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6

Graduate G from cosmological measurements

  • rbj
  • · Replies 1 ·
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1

High School Can Carbon Nanotubes Make Space Elevators a Reality?

  • DaveC426913
  • · Replies 33 ·
2
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33

Graduate An way to visualize dark matters effects on space-time?

  • freerangequark
  • · Replies 4 ·
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4

Graduate Thought Experiment on Dark Matter

  • notknowing
  • · Replies 2 ·
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2

High School Help with astronomy homework problems 7 and 8

  • ElizebethDylan
  • · Replies 1 ·
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1

Graduate What is the elusive origin of gravity?

  • wolram
  • · Replies 70 ·
3
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70

High School Agol, Interesting objects in Perseus.

  • Integral
  • · Replies 5 ·
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5

Undergrad Does Increasing Density Increase Gravity?

  • gaurav_shade
  • · Replies 27 ·
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27

Undergrad Sources on the search for Earth-like exoplanets

  • El Hombre Invisible
  • · Replies 2 ·
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2

Graduate What Is the Universe's Topology According to Recent Research?

  • Pavel
  • · Replies 25 ·
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25

High School Best cosmology and theoretical physics books for beginners

  • pkarnett
  • · Replies 5 ·
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5

Graduate Why doesn't initial homogeneity solve the horizon problem?

  • NumberTenOx
  • · Replies 9 ·
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9

Graduate Data on galaxies -good references ?

  • notknowing
  • · Replies 1 ·
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1

Undergrad Types of Supernovae: How to Distinguish Them

  • pixel01
  • · Replies 1 ·
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1

Graduate Singularity/Expanding Universe questions

  • swerdna
  • · Replies 25 ·
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25

High School Space Temperature: Is There a Temperature in Space?

  • marsi
  • · Replies 3 ·
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3

Graduate Can wormholes or other theories make interplanetary travel possible?

  • TomMac321
  • · Replies 13 ·
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13

Stargazing Looking for advice on telescope

  • Art
  • · Replies 8 ·
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8

Undergrad Solar Wind Flux: Electron/Proton Count Reaching Earth

  • spideyinspace
  • · Replies 2 ·
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2

Undergrad Weight dependent on planet size and rotation speed?

  • NHsolarguy
  • · Replies 1 ·
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1

Undergrad How much physics do I need to start learning cosmology?

  • quantumfireball
  • · Replies 7 ·
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7

Stargazing Is there a DSLR with programmable frame rate for sequential shots?

  • Telmerk
  • · Replies 3 ·
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3

Graduate Miniprobes for interstellar exploration

  • OSalcido
  • · Replies 8 ·
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8

High School Why Does the Aurora Only Occur in the North Pole?

  • spideyinspace
  • · Replies 2 ·
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2

High School Is the Milky Way Really a Spiral Galaxy?

  • pixel01
  • · Replies 2 ·
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2

High School Can Dark Matter and Dark Energy Be Used to Explain Superhero Powers?

  • Benicus
  • · Replies 4 ·
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4

Is the Rocket Equation Holding Back Space Shuttle Safety?

  • ScienceGurl
  • · Replies 26 ·
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26

Undergrad Do hydrogen fusion reactions in the sun produce neutrons or neutrinos?

  • spideyinspace
  • · Replies 6 ·
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6

Undergrad Does the Sun's fusion reaction produce neutrons or neutrinos?

  • spideyinspace
  • · Replies 4 ·
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4

Graduate Can Andromeda Detect Earth's Past with a Giant Telescope?

  • Holocene
  • · Replies 20 ·
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20

Graduate Highest Energy Cosmic Rays Linked to Violent Black Holes

  • ZapperZ
  • · Replies 8 ·
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8

Graduate What Happens When a Black Hole Evaporates Below its Schwarzschild Radius?

  • Ascending One
  • · Replies 32 ·
2
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32

Graduate Do wormholes actually exist or just mathematical artifacts?

  • bassplayer142
  • · Replies 1 ·
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1

Graduate Is metallicity a mass or number fraction?

  • malawi_glenn
  • · Replies 2 ·
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2

Graduate Evidence for Arp's cosmology and the quasar redshift hypothesis

  • pervect
  • · Replies 4 ·
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4

High School What happens to space when matter moves through it?

  • a Buddhist
  • · Replies 4 ·
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4

High School Is the Universe Actually Spiky Instead of Smooth?

  • poet
  • · Replies 2 ·
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2

Graduate Criticism of imaginary time in the Hartle-Hawking model

  • pbethala
  • · Replies 5 ·
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5

Where did the universe come from?

  • Joza
  • · Replies 13 ·
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13

Stargazing Neutrino Telescopes may have nothing to see

  • BDOA
  • · Replies 9 ·
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9

What is the Naked Eye Comet in Perseus?

  • wildman
  • · Replies 11 ·
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11

Graduate What is the Estimated Local Star Formation Rate and How Accurate is it?

  • randa177
  • · Replies 5 ·
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5

Graduate Upper limit on the rest mass of neutrinos if. .

  • UMich1344
  • · Replies 1 ·
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1

Undergrad How was Earth's 23-degree axial tilt determined?

  • plutoisacomet
  • · Replies 4 ·
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4

Undergrad Questioning the big bang theory.

  • James_Egan
  • · Replies 8 ·
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8

Graduate Is the Universe Actually a Cosmic Computer?

  • martix
  • · Replies 3 ·
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3

Undergrad What Happens in Black and White Holes?

  • DR OF DEATH
  • · Replies 26 ·
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26

Graduate Photon Energy vs. Red Shift, Inflation Theory, Acceleration

  • gtw
  • · Replies 18 ·
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18

Graduate Meaning of cosmological constant ?

  • notknowing
  • · Replies 4 ·
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4

Graduate What causes the thin vertical wind from quasar accretion disks?

  • Jorrie
  • · Replies 7 ·
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7

Graduate Does the Big Bang Theory Break Down at the Planck Time?

  • Moridin
  • · Replies 12 ·
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12

High School Does a Black hole emit anything?

  • n4nova
  • · Replies 1 ·
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1

Graduate Hubble's Redshift: Conclusions and Vacuum Solutions

  • OOO
  • · Replies 3 ·
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3

Undergrad How Much difference b2in theoritical and experimental astrophysics?

  • SuperStringboy
  • · Replies 1 ·
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1

High School Why do planets revolve in elliptical orbits?

  • spideyinspace
  • · Replies 2 ·
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2

Undergrad Can lunar surface albedo produce enough light to wash out stars for astronauts?

  • Billahertz
  • · Replies 8 ·
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8

Graduate How can we see the early universe's material if it later became our star?

  • rogerp
  • · Replies 10 ·
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10

Graduate Does the Confusing Supernova Challenge the Big Bang Theory?

  • pbethala
  • · Replies 4 ·
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4

Graduate Is the Big Bang Theory a Foolhardy Extrapolation?

  • OOO
  • · Replies 58 ·
2
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58

Graduate Big Bang and the Second Law of Thermodynamics

  • pbethala
  • · Replies 3 ·
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3

High School What Pulls the Sun? Understanding Gravitational Pull and Mass Effect

  • michelrochette
  • · Replies 7 ·
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7

Graduate Can civilizations use the entropy gap in an expanding universe for energy?

  • hammertime
  • · Replies 3 ·
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3

Graduate Will the expanding universe keep accelerating forever?

  • hammertime
  • · Replies 2 ·
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2

High School Does a planets orbit ever go chaotic?

  • Hamish Cruickshank
  • · Replies 5 ·
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5

Stargazing How to cancel out magnification in a telescope with additional lenses

  • mufan
  • · Replies 8 ·
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8

Graduate Friedmann Cosmology at T < 1 second

  • Jorrie
  • · Replies 10 ·
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10

Is Earth at Risk from Rogue Black Holes?

  • hammertime
  • · Replies 5 ·
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5

High School What Does Expanding Universe Mean?

  • Dan Tee
  • · Replies 7 ·
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7

Undergrad Universe expansion -> t = - inifinite

  • JPC
  • · Replies 5 ·
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5

Graduate Question on gravitational lensing

  • notknowing
  • · Replies 8 ·
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8
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1

High School How could the Big Bang escape its own gravitational pull?

  • kalle437
  • · Replies 3 ·
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3

Graduate Can a Photon's Energy Approach Zero?

  • jonmtkisco
  • · Replies 4 ·
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4

Undergrad Could a planet on the opposite side of the sun remain undetected?

  • Blackwing
  • · Replies 20 ·
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20

Graduate Friiedman Fun Facts to know and tell

  • jonmtkisco
  • · Replies 54 ·
2
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54

High School Will the sun orbit bodies with greater gravity than itself?

  • Destrio
  • · Replies 10 ·
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10

Graduate What are the unexpected aspects of cosmology?

  • wolram
  • · Replies 2 ·
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2

High School Finding an asteroid database by position and date

  • big man
  • · Replies 5 ·
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5

Graduate Are Wormholes at the End of Black Holes a Possible Theory?

  • riverkee
  • · Replies 3 ·
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3

Graduate Can Energy Compression Create a Black Hole?

  • randa177
  • · Replies 6 ·
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6

High School Edwin Hubble's Redshift and the Hubble Space Telescope

  • Holocene
  • · Replies 11 ·
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11

Is the Space Station Being Decommissioned?

  • ScienceGurl
  • · Replies 13 ·
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13

Graduate Could Big Rip expansion create new universes from particles?

  • CuriousGreg
  • · Replies 6 ·
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6