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 From time to timescape – Einstein’s unfinished revolution?

  • Garth
  • · Replies 74 ·
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74

Graduate How Does Accelerating Expansion Affect Space Density and Interjection?

  • keepit
  • · Replies 14 ·
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14

Graduate The universe's size : always infinite?

  • pedersean
  • · Replies 47 ·
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47

Graduate Why can't we see anything fall into the black hole?

  • Sarcastic14
  • · Replies 1 ·
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1

Discussing the Big Rip Theory: Have You Heard About It?

  • Joe L. Ogan
  • · Replies 10 ·
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10

Graduate More on faster than light neutinos

  • wolram
  • · Replies 1 ·
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1

Graduate How Should We Visualize Dark Matter Around Spiral Galaxies?

  • ryan albery
  • · Replies 2 ·
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2

What is the longest lasting non-living thing in the universe?

  • apathyinlife
  • · Replies 5 ·
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5

Graduate Existance of time before big bang

  • dhruv mishra
  • · Replies 31 ·
2
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31

Undergrad Earth's Gravity if the Earth rotated the opposite direction

  • rogersjc
  • · Replies 4 ·
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4

Graduate Big Bang or Multiverse: Which Theory Explains Our Universe Better?

  • Nervous
  • · Replies 10 ·
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Undergrad Black Hole Gravity at a Distance

  • Sothh
  • · Replies 1 ·
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1

Graduate Something is broken about black hole theory

  • x_engineer
  • · Replies 15 ·
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15

Undergrad Would a Hot star have more mass than a cooler one?

  • ArmoSkater87
  • · Replies 13 ·
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Graduate How to calculate mass of fuel needed to escape Earth gravity vs. Mars gravity

  • jhochstein
  • · Replies 2 ·
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2

Graduate Position of Ascending and Descending Nodes

  • TheHarvesteR
  • · Replies 3 ·
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3

Undergrad Calculating energy from flux and max wavelength

  • ShalinNayak
  • · Replies 1 ·
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1

Stargazing Why is magnification defined as the ratio of eye and objective lens resolution?

  • Marketo
  • · Replies 4 ·
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4

Undergrad Astronomy - Measure distance to other galaxies

  • tosv
  • · Replies 9 ·
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9

High School Why is the solar system, & galaxies seemingly rotate on a 2-D plane?

  • Techno-Raver
  • · Replies 10 ·
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10

Graduate Can cosmologist mathematicians compute all the way to absolute nothingness?

  • yrreg
  • · Replies 40 ·
2
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40

Undergrad Gravitational Effects: How Jupiter Impacts Mars' Orbit

  • Frannas
  • · Replies 3 ·
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3

Graduate Understanding Acoustic Peaks Beyond Last Scattering

  • superg33k
  • · Replies 5 ·
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5

Graduate Propagating a Hyperbolic Trajectory

  • TheHarvesteR
  • · Replies 4 ·
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4

Undergrad Could gravity be a convergence of waves?

  • cookertron
  • · Replies 3 ·
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3

Graduate How Does the Empire State Building Help Us Understand the Big Bang?

  • mak_phy
  • · Replies 7 ·
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7

Graduate Physical Difference in a Cepheid Variable

  • Vorde
  • · Replies 3 ·
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3

Graduate Chandrasekhar limit & Tolman–Oppenheimer–Volkoff limit

  • Astro.padma
  • · Replies 11 ·
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11

Graduate How close does a supernova has to be to be lethal?

  • SubTachyon
  • · Replies 5 ·
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5

High School Will the red giant sun destroy the Earth?

  • Dremmer
  • · Replies 11 ·
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11

Stargazing Spatial and Angular Resolution of a Earth observing Telescope

  • CJSGrailKnigh
  • · Replies 5 ·
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5

High School How Long Does VY Canis Majoris Have Left?

  • Newtons Apple
  • · Replies 3 ·
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3

Graduate Link between Universe mass density and Cosmic Microwave Background energy

  • johne1618
  • · Replies 3 ·
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3

High School Parallax and Perspective Explained

  • peter.ell
  • · Replies 2 ·
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2

Graduate How do massive stars like VY Canis not turn into black holes

  • blarznik
  • · Replies 6 ·
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6

Graduate Question for Astronomers about the Equinoxes

  • brocks
  • · Replies 4 ·
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4

Is There a Smaller 2-Body System Than an Asteroid and Its Moon?

  • wolram
  • · Replies 2 ·
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2

Mysterious Red Areas in M33 Triangulum Galaxy

  • Drakkith
  • · Replies 13 ·
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13

Undergrad New Results From LHC/ light speed project

  • brother time
  • · Replies 2 ·
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High School According to our weather person, Fall starts on 9/23/11, How?

  • Gannet
  • · Replies 4 ·
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4

High School Why Does the Moon's Position in the Sky Change Throughout the Month?

  • Jim Ross
  • · Replies 7 ·
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7

Graduate Could a Splatnik be the solution to space debris?

  • Tandem78
  • · Replies 4 ·
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4

Graduate Why should radiation lead to loss in mass @ Black holes?

  • Astro.padma
  • · Replies 5 ·
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5

Graduate Can We Achieve .99c for Interstellar Travel?

  • cjackson
  • · Replies 47 ·
2
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Graduate Hard evidence for quasar lensing

  • deSitter
  • · Replies 2 ·
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Graduate What Happens to Matter in a Black Hole?

  • Laywoman
  • · Replies 75 ·
3
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Graduate Does spacelike separation have anything to do with non-locality?

  • dst
  • · Replies 1 ·
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Undergrad How Do You Convert Pixel Number to Wavelength in a CCD Spectrum Analysis?

  • jaykob_hxc
  • · Replies 3 ·
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3

Undergrad How to describe position of our solar system to some ETI in other galaxy?

  • samnathan
  • · Replies 7 ·
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7

Stargazing House Appropriations Committee Kills James Webb Telescope

  • signerror
  • · Replies 38 ·
2
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38

Graduate Singularity or just a very small, massive shell?

  • em370
  • · Replies 31 ·
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31

Graduate Quantum Fluctuations and the Origin of the Cosmic Microwave Background Radiation

  • Orion1
  • · Replies 2 ·
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2

Time-lapse fly over planet Earth

  • Orion1
  • · Replies 1 ·
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1

Graduate Does Acceleration of Matter Lead to Gravitational Dilation?

  • tvscientist
  • · Replies 21 ·
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21

Graduate Gigantic Black Holes vs White Holes: How Can We Know?

  • profgemelli
  • · Replies 5 ·
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5

M101 Supernova Magnitude: Current & Future

  • DaveC426913
  • · Replies 19 ·
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19

Graduate What *would* the night sky look like if we could see the entire EM spectrum?

  • SeventhSigma
  • · Replies 11 ·
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11

Undergrad Size of planet with 1/50 gravity of earth

  • YummyFur
  • · Replies 28 ·
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28

Graduate Is the Expanding Universe Theory Reversed? A Scientist's Perspective

  • razorheno
  • · Replies 19 ·
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19

Undergrad How do they know what happened in the first second

  • bobsmith76
  • · Replies 8 ·
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8

Dwarf galaxies suggest dark matter theories may be wrong

  • phinds
  • · Replies 5 ·
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5

High School What can gravitational waves teach us about the universe?

  • sankaDM
  • · Replies 3 ·
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3

Undergrad Astronomy - Main sequence and red giants

  • tosv
  • · Replies 3 ·
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3

Graduate Habitable zone planet discovered

  • Orion1
  • · Replies 18 ·
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18

Graduate Difference between thermal and non-thermal Bremsstrahlung

  • kop442000
  • · Replies 3 ·
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3

Graduate Messier 101 (The Pinwheel Galaxy) and SN 2011 fe (PTF 11kly)

  • IonicOne
  • · Replies 2 ·
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2

Undergrad What is the Area in Kepler's 2nd Law?

  • uppaladhadium
  • · Replies 1 ·
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1

Undergrad Detecting Cosmic Dust: The Challenges and Solutions

  • tosv
  • · Replies 6 ·
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6

Undergrad Intelligent life in the universe

  • AdamMc85
  • · Replies 1 ·
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1

Undergrad Orbits, ellipitical, circular, or ?

  • flyingpig
  • · Replies 2 ·
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2

Graduate Sunspots, areas of intense magnetic fields.

  • chemisttree
  • · Replies 9 ·
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9

Undergrad Will the earth and sun ever be tidally locked?

  • ARAVIND113122
  • · Replies 16 ·
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16

Where can I find captivating videos for my Big Bang presentation?

  • rohlrogge
  • · Replies 1 ·
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1

Graduate The Mystery of CMB Polar Anisotropy and its Implications on Cosmology

  • profgemelli
  • · Replies 20 ·
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20

High School How do we know everything in the universe is made of atoms?

  • TehEpicness
  • · Replies 13 ·
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13

NASA Discovers Planet With 2 Suns

  • Imax
  • · Replies 3 ·
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3

Graduate Supermassive BH feeding on Dark matter

  • Dmitry67
  • · Replies 8 ·
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8

Graduate What is the significance of Eq. 15 in the expansion of HII regions?

  • matteo86bo
  • · Replies 4 ·
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4

Graduate Space Elevator: Magnitized Cable for Supersonic Travel

  • Vinni
  • · Replies 14 ·
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14

Graduate Gravitational Waves: Interfering, Diffracting & More

  • Drakkith
  • · Replies 20 ·
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20
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1

What Makes an Effective Astrophysics Blog?

  • Astro.padma
  • · Replies 2 ·
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2

Undergrad Example of a mass orbiting more massive, less luminous body?

  • Deadstar
  • · Replies 4 ·
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4

High School Can a Planet Explode Like a Star?

  • flyingpig
  • · Replies 31 ·
2
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31

Graduate Gravity: How Does Spacetime Bend?

  • cueball B
  • · Replies 7 ·
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7

Graduate Vega. Are Sol and Vega destined to collide?

  • twistedspark
  • · Replies 4 ·
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4

High School Kepler 16-b: first circumbinary planet?

  • arjose
  • · Replies 6 ·
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6

Graduate Unify Fields in Big Bang: Quest for Origin

  • easyrider
  • · Replies 11 ·
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11

Undergrad Can a sun rise and set on the same horizon?

  • Razorback-PT
  • · Replies 15 ·
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15

New 3D model of solar system and night sky

  • Mito111
  • · Replies 9 ·
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9

Undergrad Has anyone tried Victor Stenger's MonkeyGod toy universe program?

  • marcus
  • · Replies 3 ·
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3

Graduate Can infinity fit in the palm of your hand

  • YummyFur
  • · Replies 34 ·
2
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34

Graduate Effect of lunar/solar gravity on shape of earth

  • daniel6874
  • · Replies 86 ·
3
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86

Colourful moon dog observed, or what?

  • arildno
  • · Replies 2 ·
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2

Graduate Why Do Scalar Fields in Hybrid Inflation Model Diverge with Large Mixing Term?

  • Accidently
  • · Replies 5 ·
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5

Graduate I would like to know more about the beginning of time in terms of

  • nard
  • · Replies 1 ·
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1

Undergrad An impractical but difficult problem I stumbled upon

  • bigmoneyhat
  • · Replies 2 ·
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2

Undergrad Mass of the core of the sun > mass of the sun?

  • h1a8
  • · Replies 3 ·
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3

Graduate What would happen if two Earth size planets very slowly collided?

  • blarznik
  • · Replies 19 ·
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19

Graduate Gravitational Variances in Space

  • Maximilan
  • · Replies 6 ·
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6