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 Relation to an Accelerated Expanding Universe

  • PVastro
  • · Replies 12 ·
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12

Human Limitations of understanding.

  • shifty88
  • · Replies 4 ·
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4

Graduate Does the Spin of a Supermassive Black Hole Influence Its Galaxy's Rotation?

  • TRB8985
  • · Replies 16 ·
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16

Graduate Shouldn't we have heard alien radio signals by now? Why not?

  • SeventhSigma
  • · Replies 52 ·
2
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52

Graduate Unveiling the Mystery of Magnetic Fields in Space

  • Lesnick
  • · Replies 5 ·
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5

Undergrad How Can I Predict When Venus Will Be Visible as an Evening or Morning Star?

  • Cantstandit
  • · Replies 4 ·
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4

Graduate Surface gravity as a function of luminosity?

  • Mr. Bond
  • · Replies 4 ·
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4

Graduate Why Does NGC 7603's Bridge Defy Redshift Expectations?

  • SeventhSigma
  • · Replies 4 ·
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4

Undergrad Does outer space just have two spatial dimensions.

  • Dremmer
  • · Replies 1 ·
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1

Graduate How Do Scientists Use Zircons to Date the Earth's Formation?

  • Wallis
  • · Replies 18 ·
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18

Undergrad Phenomenon of rotation of planets

  • dpa
  • · Replies 9 ·
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9

Graduate Is There Such a Thing as Dark Time?

  • geelsu
  • · Replies 30 ·
2
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30

Graduate How can I recognize H alpha line?

  • 19matthew89
  • · Replies 1 ·
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1

Undergrad Energy Density of a magnetic field

  • Macarenses
  • · Replies 1 ·
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1

Graduate How does CMB support the predictions of inflation ?

  • lalbatros
  • · Replies 15 ·
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15

Graduate Question about a torodial universe

  • Vorde
  • · Replies 5 ·
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5

High School Venus: Looking for Life Beyond Earth

  • Vinni
  • · Replies 9 ·
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9

Graduate Flatness-infiniteness logical problem

  • supermarina
  • · Replies 11 ·
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11

Graduate Critical density and observable mass

  • jimjohnson
  • · Replies 4 ·
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4

Graduate What would happen to black holes if Lambda increased?

  • marcus
  • · Replies 13 ·
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13

Undergrad Expansion and Contraction of Universe

  • vinayjain
  • · Replies 30 ·
2
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30

Undergrad Space Freighters: Can Containers Take Off & Land Themselves?

  • Kitchengoblin
  • · Replies 17 ·
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17

Graduate Recycling of gas and other materials in galaxies

  • H2Bro
  • · Replies 1 ·
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1

Graduate The Properties of Jupiter's Core that give it magnetism?

  • electron_man
  • · Replies 1 ·
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1

Graduate Can Scientists Locate the Center of the Universe?

  • nihilius
  • · Replies 3 ·
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3

Graduate Liberate all the matter from a black hole

  • ugalpha
  • · Replies 31 ·
2
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31

Graduate What is the concept of mass splitting?

  • PCSL
  • · Replies 12 ·
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12

Graduate A thought experiment regarding the nature of space expansion

  • salvestrom
  • · Replies 30 ·
2
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30

Graduate Is space-time flat or curved over time?

  • Gill tunnel
  • · Replies 7 ·
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7

Undergrad Why Are Giant Stars So Low in Density?

  • triabva2003
  • · Replies 6 ·
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6

Undergrad Goldilocks Zone: A Widened Definition

  • Nigle Amar
  • · Replies 10 ·
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10

Graduate Singularity, Infinity, Edge, Expansion

  • Flustered
  • · Replies 34 ·
2
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34

High School Do Solar Flares Increase Sunburn Risk?

  • tf22raptor
  • · Replies 1 ·
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1

High School Layman's question on Cosmic Microwave Background

  • FalkonJenova
  • · Replies 7 ·
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7

Graduate Why are spiral galaxies generally planar?

  • newtonsdad
  • · Replies 10 ·
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10

Graduate Does Dark Matter Really Exist? A Look at Alternative Theories in Astrophysics

  • Swankie
  • · Replies 28 ·
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28

Graduate Fridman's Equation: Understanding Lambda, K, and the Hubble Parameter

  • supermarina
  • · Replies 6 ·
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6

Graduate How does the tilt and orbit of a planet affect its analemma shape?

  • Swankie
  • · Replies 1 ·
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1

The Universe - infinite or not ?

  • drag
  • · Replies 139 ·
5
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139

Undergrad Can Spider Silk Be Used As Space Tethers?

  • geordief
  • · Replies 4 ·
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4

Graduate 'A Universe From Nothing' by Lawrence Krauss, AAI 2009

  • Schlofster
  • · Replies 63 ·
3
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63

High School Gravity & Universe: Is Everything Falling?

  • cottonkat5
  • · Replies 5 ·
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5

Graduate Tidal lock due to rotation of displaced mass

  • Dmstifik8ion
  • · Replies 1 ·
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1

Undergrad Astrometeorology: A real science?

  • LightbulbSun
  • · Replies 20 ·
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20

Graduate Why Don't Distant Objects Fade to Black?

  • mnb96
  • · Replies 22 ·
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22

High School Pulsars: fluctuating speed of rotation?

  • likewhaaa
  • · Replies 2 ·
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2

Undergrad Expanding Universe: What We See & How We Know

  • Swimfit
  • · Replies 33 ·
2
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33

Graduate What is the basis for the theory that WIMPs could be detected by

  • sahmgeek
  • · Replies 6 ·
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6

Undergrad Are Black Holes Real Holes or Just Theoretical Constructs?

  • eirhnh
  • · Replies 23 ·
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23

Undergrad Questions concerning hypervelocity stars

  • Travito
  • · Replies 9 ·
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9

Stargazing Any tips for amateur astrophotography beginners?

  • Adyssa
  • · Replies 3 ·
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3

High School Oxygen, and space what are the effects?

  • DubaUe
  • · Replies 16 ·
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16

Graduate Dark Matter, Dark Energy, Dark Flow ohh

  • rhody
  • · Replies 12 ·
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12

High School What is the size of the universe

  • jbander
  • · Replies 5 ·
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5

Graduate Can expansion be due to large-scale curvature?

  • claycravens
  • · Replies 3 ·
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3

Graduate How Do Eclipses Affect the B-V Index of Identical Binary Stars?

  • Fernsanz
  • · Replies 1 ·
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1

High School Proxima Centauri closest star. super nova

  • budd
  • · Replies 20 ·
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20

Graduate Loss of obliquity on mars and its consequences toward life

  • Nano-Passion
  • · Replies 4 ·
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4

Undergrad Calculating the period of an orbit

  • solarblast
  • · Replies 4 ·
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4

Undergrad Discovering the Universe's Flatness: Insights from an Amateur Astronomer

  • CCosmin
  • · Replies 13 ·
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13

Stargazing Your Thoughts on a High Altitude Telescope

  • Drakkith
  • · Replies 19 ·
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19

Graduate Black hole complementarity and omnipresence

  • skydivephil
  • · Replies 1 ·
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1

Graduate Fermions in Early Universe: Why We Ignore Them?

  • Accidently
  • · Replies 3 ·
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3

Undergrad Universe radius 1,000 years ago?

  • termina
  • · Replies 4 ·
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4

Undergrad Calculating Energy of Separating Stars: Potential vs Kinetic Energy

  • zezima1
  • · Replies 3 ·
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3

Graduate Into what dimension is Spacetime Curved?

  • PhanthomJay
  • · Replies 23 ·
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23

High School Can Planets Revolve Without Rotating and What Determines Their Direction?

  • revelation101
  • · Replies 14 ·
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14

Graduate Neutrinos & Gravity: Faster than Light?

  • keepitmoving
  • · Replies 10 ·
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10

High School Possible Explanation for Red Flickering of Betelgeuse Star in the Night Sky

  • Johnahh
  • · Replies 8 ·
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8

Graduate Visualizing Alfven Waves in a Spherical Galaxy

  • sparkle123
  • · Replies 2 ·
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2

Graduate Does a black hole really have mass?

  • Jimmy9
  • · Replies 13 ·
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13

Graduate Orbital Elements-Identification of method

  • solarblast
  • · Replies 3 ·
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3

Undergrad Expanding Universe-Colliding Galaxies?

  • Jimmy9
  • · Replies 4 ·
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4

Graduate Is there an absolute motionless?

  • evangoor
  • · Replies 9 ·
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9

Graduate Scanning pattern in Planck's maps

  • zonde
  • · Replies 4 ·
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4

High School Do stars actually collide in galactic collisions?

  • bostonnew
  • · Replies 16 ·
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16

Graduate Inflation and accelerated expansion of the universe

  • alvarogz
  • · Replies 1 ·
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1

Graduate Spacetime expansion effects on wavelength of travelling light

  • H2Bro
  • · Replies 1 ·
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1

Graduate How Long to Ingest an Earth-Size Planet?

  • wolram
  • · Replies 6 ·
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6

Undergrad Gravity and space curvature confusion

  • ax53
  • · Replies 10 ·
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10

Graduate Quantum entanglement and black holes

  • bled_eidol
  • · Replies 16 ·
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16

Graduate Planetary Systems within Elliptical Binary Stars?

  • MrMojo1
  • · Replies 3 ·
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3

Graduate What do the processes of first, second and third dredge-up do with a

  • eXorikos
  • · Replies 2 ·
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2

Cannot see the milky way in dublin?

  • gttjohn
  • · Replies 15 ·
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15

Graduate Difference between blast & shock wave

  • Jain_Mor
  • · Replies 5 ·
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5

High School Time Earth reached its Perihelion

  • Philosophaie
  • · Replies 5 ·
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5

Graduate Is There Experimental Proof of Dark Energy and Antigravity?

  • revelation101
  • · Replies 3 ·
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3

Graduate Supernova explosion near a black hole

  • vinayjain
  • · Replies 6 ·
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6

Stargazing New Celestron CPC 925 XLT Telescope Arrives - Dave's Story

  • davenn
  • · Replies 7 ·
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7

Graduate Ultimate fate of the universe via a Bose-Einstein condensate

  • Dale79J
  • · Replies 3 ·
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3

Stargazing Go with the Orion Skyview pro 120mm refractor

  • BreMatthews
  • · Replies 3 ·
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3

Graduate Why Is the Universe Non-Uniform Despite Uniform Physical Laws?

  • thedragonbook
  • · Replies 44 ·
2
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44

Graduate The source of cosmic background radiation

  • Lesnick
  • · Replies 5 ·
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5

Graduate If the universe is truly expanding, why aren't any stars getting dimmer?

  • dcorbett
  • · Replies 9 ·
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9

Graduate Deflection of light passing close to the sun

  • Lesnick
  • · Replies 5 ·
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5

High School Milky Way's Supermassive Black Hole to Light Up in 2013?

  • chemisttree
  • · Replies 9 ·
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9

A question with a purpose for other thoughts.

  • DubaUe
  • · Replies 1 ·
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1

Where Did the Mysterious Metal Balls Falling from Space Come From?

  • surajt88
  • · Replies 8 ·
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8

Graduate Stephen Hawking says there is no God. But,

  • William Tu
  • · Replies 33 ·
2
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33

Graduate What time of year observations of crab pulsar were made

  • SUDOnym
  • · Replies 3 ·
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3