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

Would you book online a travel to outer space?

  • maxmaxus
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Graduate Can a universe exist with no matter?

  • Dremmer
  • · Replies 9 ·
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9

Graduate Does the zero-energy universe contradict energy conservation?

  • Naty1
  • · Replies 9 ·
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9

Graduate How can the distance duality relation be derived in a model-independent way?

  • aymer
  • · Replies 1 ·
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1

Undergrad Finding apparent and absolute magnitude from a Cepheid's period

  • Ivan91
  • · Replies 3 ·
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3

Graduate Is Dark Matter Only Present on a Galactic Scale?

  • alvarogz
  • · Replies 7 ·
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7

Can we see the image of earth coming back to us after space travel

  • asimations
  • · Replies 2 ·
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2

Undergrad Why do Planets have elliptical orbits ,AND

  • gttjohn
  • · Replies 10 ·
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10

Undergrad Difference between black holes and wormholes

  • Jadaav
  • · Replies 6 ·
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6

Graduate Why aren't human biological processes gravity-dependent?

  • asimations
  • · Replies 2 ·
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2

Graduate Does modern physics support external causation for the universe's origin?

  • NihilNominis
  • · Replies 9 ·
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9

Graduate Laws of Physics may change across the Universe

  • AdkinsJr
  • · Replies 1 ·
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1

Undergrad Dark Energy & Expanding Universe: Newtonian Perspective

  • darkside00
  • · Replies 11 ·
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11

High School Does the Earth get bigger from the sun?

  • leonstavros
  • · Replies 5 ·
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5

Graduate Expansion and Conservation of Energy

  • mrspeedybob
  • · Replies 10 ·
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10

Undergrad What are the best RSS feeds for the latest astrophysics research?

  • Simfish
  • · Replies 1 ·
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1

Graduate If the big crunch occurred, would time go backwards?

  • Dremmer
  • · Replies 8 ·
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8

Undergrad Finding Earth's orbital period with Kepler's third law

  • DB
  • · Replies 12 ·
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12

Graduate What are the Names of the Points on a Space Elevator's Path?

  • Eagle9
  • · Replies 5 ·
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5

Stargazing How does atmospheric turbulence affect lunar eclipse photography?

  • Dembadon
  • · Replies 16 ·
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16

High School Some very basic Astronomy questions

  • yalgaar
  • · Replies 7 ·
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7

Graduate What Is the Mechanism Behind Dark Flow?

  • filegraphy
  • · Replies 7 ·
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7

Graduate Does gravitational dilution affect timescales in the early universe?

  • TungstenX
  • · Replies 10 ·
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10

High School What Did the Universe Look Like from the Big Bang to Now?

  • SeventhSigma
  • · Replies 9 ·
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9

Graduate Empirical measurement of the expansion of the universe

  • BernieM
  • · Replies 8 ·
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8

Graduate Is Quantum Astrophysics a Subfield of Astrophysics?

  • Fysics
  • · Replies 1 ·
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1

Undergrad Is Time Affected by Space in the Universe?

  • lay-man
  • · Replies 7 ·
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7

High School I think Eddington cooked the books .

  • DAANEL
  • · Replies 3 ·
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3

Stargazing Rare Total Lunar Eclipse on Winter Solstice - Dec 21 @12:29AM EST

  • Philosophaie
  • · Replies 2 ·
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2

Graduate Maximum redshift - can it move light off the scale?

  • misterkel
  • · Replies 4 ·
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4

Graduate Universal fractal structure and the infinite universe

  • Iam.HG
  • · Replies 3 ·
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3

Graduate Detecting Dark Matter with Germanium Atoms

  • nlsherrill
  • · Replies 16 ·
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16

Undergrad Number of intelligent civilizations over the history of the galaxy

  • madman143
  • · Replies 2 ·
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2

Undergrad Inflatable plastic domes for Martian settlements instead of glass

  • Protonic
  • · Replies 7 ·
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7

Graduate Is the popular understanding of C.M.B.R. too simplistic?

  • Peter Watkins
  • · Replies 43 ·
2
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43

High School Is the Universe Like the Inside Of A Spherical Mirror

  • Godswitch
  • · Replies 4 ·
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4

High School What is a Morton Wave on the Sun?

  • davenn
  • · Replies 2 ·
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2

Graduate What would happen if two black holes collided?

  • Sniperman724
  • · Replies 2 ·
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2

Undergrad What happens if you cool and slow down solar particles?

  • TungstenX
  • · Replies 6 ·
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6

Undergrad Is space an insulator? Why do satellites stay warm?

  • dotancohen
  • · Replies 14 ·
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14

Undergrad Blocks of empty space within the known universe

  • eksxxx
  • · Replies 3 ·
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3

Graduate Is the Cosmic Expansion Merely a Result of Heisenberg's Uncertainty Principle?

  • Inductor
  • · Replies 2 ·
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2

Undergrad Does interstellar dust or stars contribute more to non-dark matter?

  • ClamShell
  • · Replies 7 ·
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7

Graduate Life and the size of the universe

  • Mazuz
  • · Replies 11 ·
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11

Undergrad Trajectory of object around the moon as function of time

  • Henriklm
  • · Replies 7 ·
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7

Graduate Pulsar Timing Accuracy: Fractional Instability to 10^-15

  • mersecske
  • · Replies 1 ·
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1

High School How to determine moon phase from positions of sun and moon

  • chod
  • · Replies 3 ·
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3

Graduate How much will the planck mission resolve about the universe.

  • wolram
  • · Replies 1 ·
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1

What is the Purpose of Black Holes?

  • Willowz
  • · Replies 12 ·
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12

Graduate Are Proto-Photons the Only Matter at the Outer Limits of the Universe?

  • foolosophy
  • · Replies 18 ·
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18

Graduate Initial state based on current state?

  • PhysDrew
  • · Replies 18 ·
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18

Stargazing Best compromise for portable telescope?

  • jnorman
  • · Replies 12 ·
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12

Graduate Is There a Universe Beyond Our Own?

  • RandyDisher
  • · Replies 4 ·
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4

Graduate Does the Big Crunch involve space contracting or just galaxies collapsing?

  • ericksvensson
  • · Replies 36 ·
2
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36

Graduate Force on a Swinging Rod (space elevator)

  • msion
  • · Replies 1 ·
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1

Graduate Could the inflation epoch carry information faster than c

  • ensabah6
  • · Replies 3 ·
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3

Undergrad How to test a parabolic mirror?

  • sergeant_pv
  • · Replies 4 ·
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4

Graduate Can Hawking Radiation explain the immortality of neutron stars?

  • Dremmer
  • · Replies 24 ·
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24

Graduate Faster than light and way smaller than electrons

  • asimations
  • · Replies 4 ·
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4

Graduate Do planets follow the curvature of spacetime as they orbit?

  • Dusty_Matter
  • · Replies 10 ·
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10

Graduate Movement of Galaxies in relation to each other

  • GiZeHy
  • · Replies 4 ·
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4

Graduate Bumping bubbles from our pre-bang past ( test of eternal infl.)

  • marcus
  • · Replies 9 ·
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9

Undergrad Is Time Travel Possible Through Black Holes?

  • philophysics3
  • · Replies 8 ·
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8

Graduate Is Time Really a Fourth Dimension Similar to Spatial Dimensions?

  • MattRob
  • · Replies 3 ·
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3

Graduate Frame dragging around a rotating black hole.

  • Imax
  • · Replies 18 ·
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18

Undergrad Will every possibility occur infinitely in an endless expanding universe?

  • Brasse94
  • · Replies 1 ·
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1

Graduate How can matter change the geometry of spacetime?

  • Brasse94
  • · Replies 1 ·
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1

Undergrad How did Kepler know the sun was at one focus of ellipses?

  • stonecoldgen
  • · Replies 1 ·
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1

Graduate Is the Entropy of Black Holes Proportional to Their Size?

  • brcooke
  • · Replies 20 ·
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20

Graduate Without Dark Matter and Dark Energy

  • cbd1
  • · Replies 15 ·
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15

Undergrad How can we see stars past 13.5 billion light years away?

  • dcderek24
  • · Replies 6 ·
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6

Undergrad What exactly are Magnetars? I've heard the term used before, and all I

  • fillipeano
  • · Replies 4 ·
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4

Graduate Existence of super-massive black holes

  • sri sharan
  • · Replies 11 ·
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11

Undergrad Can light be accelerated by a black hole's gravity?

  • Andrejck
  • · Replies 10 ·
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10

Undergrad Nobody has yet seen an extraterrestrial, but scientists have found

  • University
  • · Replies 3 ·
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3

Undergrad Why is Saturn's atmosphere less stormy than Jupiter's?

  • nukeman
  • · Replies 4 ·
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4

12.5 billion years ago what did

  • rrw4rusty
  • · Replies 1 ·
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1

Graduate Penrose and Gurzadyan respond to CMB low variance circle criticism

  • marcus
  • · Replies 19 ·
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19

Graduate Trying to understand the Shape of the universe.

  • dubsed
  • · Replies 10 ·
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10

Graduate Does metric expansion of space mean matter also expands?

  • Landrew
  • · Replies 30 ·
2
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30

High School Why don't galaxies form giant solar systems?

  • harp AP 2010
  • · Replies 10 ·
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10

High School Does Earth's mass of 5.97×10^24 kg include people and buildings?

  • kk727
  • · Replies 11 ·
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11

Undergrad What factors make landing on Mars easier than on the Earth? Harder?

  • nukeman
  • · Replies 7 ·
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7

Graduate Solving N-Body Simulation Problems with Gravitational Equations

  • Lijnk
  • · Replies 8 ·
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8

Undergrad Galaxies - spiral arms split, why?

  • precisionart
  • · Replies 6 ·
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6

Undergrad Can you detect black holes through their radiation?

  • RebelRiver
  • · Replies 6 ·
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6

Undergrad Stars: Creation, destruction and impact on the universe

  • moonkey
  • · Replies 1 ·
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1

Graduate Where does space come from in an expanding universe?

  • 36grit
  • · Replies 12 ·
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12

How can we define the universe as having a shape ?

  • AshsZ
  • · Replies 7 ·
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7

Undergrad Solving Sun-Earth-Moon Orbit Problem with Solar System Simulator

  • Smoove
  • · Replies 28 ·
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28

Graduate Photon Red Shift Energy losses in expanding universe theories

  • alexjbuck
  • · Replies 11 ·
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11

High School Questions regarding Earth life came from Mars - ? - Thanks

  • nukeman
  • · Replies 5 ·
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5

High School Is 1 AU measured from Earth's center or surface?

  • wg1337
  • · Replies 17 ·
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17

Graduate Dark disc constraints from missing Milky Way dark matter

  • Grep
  • · Replies 7 ·
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7

Undergrad Were red dwarfs once as luminous as the Sun?

  • MathematicalPhysicist
  • · Replies 11 ·
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11

Graduate No evidence for circles in the CMB; contrary to claims by Penrose and Gurzadyan

  • nicksauce
  • · Replies 4 ·
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4

Graduate Is Space More Fundamental Than Time in Our Universe?

  • Dremmer
  • · Replies 1 ·
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1

Graduate Penrose claims WMAP evidence of pre-Big Bang activity

  • Grep
  • · Replies 43 ·
2
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43

Undergrad Is Time the Movement of Matter Through Space?

  • erausch
  • · Replies 16 ·
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16

Graduate What Determines the Order of Stars Hitting a Black Hole's Event Horizon?

  • thedeester1
  • · Replies 2 ·
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2