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 Why is Mars so easily visible to the naked eye?

  • Solon
  • · Replies 8 ·
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8

Undergrad What Form Does Matter Take When a Star 'Explodes'?

  • wawatson
  • · Replies 11 ·
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11

Undergrad See far away objects in space in real time?

  • robertito
  • · Replies 4 ·
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4

When Will We Know If Planck Discovered B Mode Polarisation?

  • skydivephil
  • · Replies 9 ·
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9

Graduate Coincidence of asteroid and Russian meteor at same time.

  • RGregoryClark
  • · Replies 10 ·
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10

Graduate Largest structure in the universe discovered so far

  • PhysicsDad
  • · Replies 7 ·
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7

Graduate Original location of the Big Bang

  • Jack Bauer
  • · Replies 42 ·
2
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42

Undergrad Is the Moon's Orbit Influenced by Earth's Warped Space and Tidal Friction?

  • a.alexandra
  • · Replies 16 ·
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16

Graduate What Are the Key Experiments for Investigating Redshift Anomalies?

  • codex34
  • · Replies 14 ·
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14

Graduate Why Isn't the Entire Universe a Black Hole Despite the Big Bang Singularity?

  • gregtomko
  • · Replies 28 ·
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28

Undergrad Calculate the equatorial rotation velocity

  • Vetmora
  • · Replies 8 ·
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8

Undergrad Kepler's 3rd law - which object in numerator?

  • aphysicsmanduh
  • · Replies 2 ·
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2

Graduate Is the Expansion of the Universe Accelerating Beyond the Speed of Light?

  • MostlyHarmless
  • · Replies 2 ·
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2

Undergrad Do planets wave in their orbits?

  • Kev2013
  • · Replies 2 ·
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2

Graduate Would a Universe be considered part of the standard model?

  • NWH
  • · Replies 4 ·
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4

Graduate Is Gravitational Energy Truly Negative in a Zero-Energy Universe?

  • InvalidID
  • · Replies 5 ·
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5

Graduate Inflation, as a tool for supersymmetry breaking

  • pleasehelpmeno
  • · Replies 3 ·
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3

Undergrad Astronomy paper help - professor doesn't understand my wording

  • Lyrassia
  • · Replies 15 ·
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15

High School Solar system is bigger than previously thought

  • PhilDSP
  • · Replies 1 ·
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1

Graduate Could You Have Spotted the TanDEM-X Satellites Near Saturn?

  • PhilDSP
  • · Replies 5 ·
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5

High School Can you recommend any resources for Astronomy?

  • athena810
  • · Replies 4 ·
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4

Graduate Questions on observational cosmology

  • pleasehelpmeno
  • · Replies 3 ·
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3

High School Why doesn't the moon eventually drift into space?

  • pheadden
  • · Replies 9 ·
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9

Graduate Earliest Rocky Planets: Timeframe & Info

  • andygee
  • · Replies 10 ·
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10

Graduate Travel to another moon/planet/gravitational body

  • season89
  • · Replies 4 ·
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4

Graduate What is the source of dark energy?

  • DiracPool
  • · Replies 6 ·
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6

High School Can We See If A Planet Is Inhabited 1 Million Lightyears away?

  • DIYMobileAudio
  • · Replies 12 ·
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12

Graduate How do Trojan Asteroids effect a planets' orbits

  • Eric M. Jones
  • · Replies 10 ·
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10

Experience the Incredible Descent onto Titan: How Did They Do It?

  • Garth
  • · Replies 7 ·
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7

Graduate What is the fabric of the universe?

  • petm1
  • · Replies 45 ·
2
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45

Graduate Auroral Mechanism: Questions Answered

  • Thunderclap
  • · Replies 2 ·
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2

Undergrad Looking for a good analogy of the shape of the expanding universe

  • Andrew Bone
  • · Replies 3 ·
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3

Third Van Allen Belt Discovered - NASA Probes

  • Mordred
  • · Replies 3 ·
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3

Graduate Gravitino production in the early universe.

  • pleasehelpmeno
  • · Replies 1 ·
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1

Graduate What Are the Processes for Manufacturing Elements Heavier Than Iron in Stars?

  • shounakbhatta
  • · Replies 14 ·
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14

Undergrad C/2013 A1: Weight Estimation & Final Trajectory

  • Ottlite
  • · Replies 2 ·
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2

Graduate Universe older than thought? Or big bang theory wrong?

  • Vierstein
  • · Replies 26 ·
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26

High School How is one black hole is larger than another?

  • htapps
  • · Replies 2 ·
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2

High School Comets in the Northern Hemisphere vs the Southern?

  • Vorde
  • · Replies 1 ·
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1

Graduate What are e-foldings and how are they used in various fields of study?

  • Mordred
  • · Replies 3 ·
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3

Time Magazine: Dark Matter May Not Exist At All

  • d3mm
  • · Replies 3 ·
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3

Graduate What happens when a black hole devours another black hole?

  • Chemist@
  • · Replies 19 ·
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19

Undergrad Why are MACHOs in the Halo not the disk

  • Daniel_G
  • · Replies 8 ·
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8

Graduate Opinion: Double Degeneracy Model for SN Ia Progenitors

  • Chronos
  • · Replies 1 ·
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1

Graduate What is the significance of the Jeans length in cloud collapse?

  • AbsoluteZer0
  • · Replies 2 ·
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2

Undergrad When did nuclear fusion in the sun really start ?

  • dsr52
  • · Replies 8 ·
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8

Undergrad Help Solve Supernova Assignment | Astro Community

  • Froddo
  • · Replies 3 ·
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3

Graduate Life in Vastly Different Universes

  • Krunchyman
  • · Replies 2 ·
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2

High School ~12mm EP and a barlow or just one good ~6mm EP

  • QuantumPion
  • · Replies 1 ·
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1

Undergrad Which Celestial Body in the Solar System Allows a Probe to Orbit Fastest?

  • Numeriprimi
  • · Replies 2 ·
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2

High School What are the best eyepieces for my new Orion XT8 telescope?

  • QuantumPion
  • · Replies 14 ·
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14

Undergrad Discovering Exoplanets: The Benefits of Studying White Dwarfs

  • skydivephil
  • · Replies 16 ·
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16

High School How close does a spacecraft get to Tethys during a mission?

  • Numeriprimi
  • · Replies 1 ·
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1

High School Why doesn't light travel infinitely fast ?

  • sikkemike
  • · Replies 37 ·
2
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37

Undergrad Accelerating Universe: Stephen Hawking, Carl Sagan, Arthur C. Clarke

  • Baltic
  • · Replies 13 ·
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13

Graduate Probability of stars in a multiverse

  • jimjohnson
  • · Replies 61 ·
3
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61

Graduate Is There Evidence for the Universe's Expansion and a Constant Speed of Light?

  • Drmarshall
  • · Replies 3 ·
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3

High School Is Andromeda Really the Nearest Galaxy to the Milky Way?

  • shounakbhatta
  • · Replies 1 ·
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1

Graduate Rotation speed of a neutron star

  • shounakbhatta
  • · Replies 9 ·
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9

Undergrad Does the Universe have a Frame Rate ?

  • Braders790
  • · Replies 11 ·
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11

Graduate Can We See Our Own Solar System Through Gravity's Mirror?

  • Slait
  • · Replies 4 ·
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4

Stargazing Is it possible to clean a telescope mirror?

  • jim hardy
  • · Replies 3 ·
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3

High School What Determines Planetary Speeds?

  • fouad89
  • · Replies 6 ·
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6

Graduate Will water or lava freeze in space, or would it be a gas?

  • Albertgauss
  • · Replies 4 ·
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4

Undergrad Why does air rush in from colder to hotter space and not vice versa?

  • jamesb100
  • · Replies 7 ·
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7

Graduate Is there a limit to the universe's expansion?

  • lmoh
  • · Replies 17 ·
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17

Graduate Before Inflation: Elementary Particles Q&A

  • big_bounce
  • · Replies 17 ·
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17

Graduate Thermal velocity of particles in the solar corona

  • Cerdocyon
  • · Replies 2 ·
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2

Undergrad Earth as Moon of Gas Giant: Effects on Sunlight?

  • willstaruss22
  • · Replies 7 ·
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7

Undergrad Easy steps to groom TabCosmo output for PF post format

  • marcus
  • · Replies 2 ·
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2

Graduate Higgs Boson Particle: Doom for the Universe?

  • DiracPool
  • · Replies 3 ·
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3

Graduate Orbiting the Sun beyond the Hill sphere

  • xpell
  • · Replies 6 ·
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6

Graduate Age versus Size of the Universe

  • Johninch
  • · Replies 40 ·
2
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40

Graduate Inflaton after chaotic inflation

  • pleasehelpmeno
  • · Replies 4 ·
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4

What Are the Largest Structures in Our Universe?

  • Naty1
  • · Replies 1 ·
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1

Unlock the Mystery: Dark Matter Discovery

  • DiracPool
  • · Replies 7 ·
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7

Graduate How precise can Doppler shift be measured in detecting exo-planets?

  • Daaavde
  • · Replies 1 ·
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1

Graduate Big Bang & Entropy: Proof & Theories Explained

  • Cantor
  • · Replies 8 ·
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8

Graduate Combining estimated errors (galaxy properties, observational)

  • Jean Tate
  • · Replies 5 ·
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5

Stargazing Help is needed in understanding my telescope

  • grobertsx
  • · Replies 5 ·
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5

High School Percentage of stars that become black holes

  • revo74
  • · Replies 10 ·
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10

Graduate Can matter focus neutrinos in a supernova event?

  • Spinnor
  • · Replies 4 ·
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4

Undergrad Creating a Equation to Destroy the Sun

  • hgivens07
  • · Replies 5 ·
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5

Graduate A way to ripple the fabric of space?

  • dilsfunspot
  • · Replies 1 ·
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1

High School Geminid meteor goes the wrong way.

  • Darwin123
  • · Replies 12 ·
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12

Graduate Thoughts and questions about the CMBR.

  • Endervhar
  • · Replies 25 ·
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25

Graduate The farthest matter we will ever hear from

  • marcus
  • · Replies 3 ·
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3

Undergrad Question about Expansion Speed exceeding Ligth Speed

  • Noaly
  • · Replies 3 ·
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3

Undergrad Chelyabinsk Meteor Shockwave 2/15/2013

  • TravelinTom
  • · Replies 21 ·
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21

Graduate Curious about Black hole information paradox

  • Akshay_Anti
  • · Replies 8 ·
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8

Undergrad Why did the Chelyabinsk Meteor Explode?

  • Zorwell
  • · Replies 9 ·
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9

Undergrad Star collapse to form directly a black hole

  • shounakbhatta
  • · Replies 3 ·
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3

Graduate Supernova remnants & neutron star

  • shounakbhatta
  • · Replies 6 ·
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6

Graduate Solution to the cosmological constant problem

  • Chronos
  • · Replies 6 ·
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6

Graduate What do we know about Baryogenesis?

  • pdyxs
  • · Replies 3 ·
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3

Undergrad Does Jupiters moon Io exhibit plate tectonics?

  • willstaruss22
  • · Replies 1 ·
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1

High School Is Russian meteor related to a asteroid known as 2012 DA14?

  • M@2
  • · Replies 10 ·
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10

Graduate Expanding Space-time and the active vaccuum.

  • geordief
  • · Replies 4 ·
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4

Graduate Nodal Precession Rates of Solar System Planets

  • Kev2013
  • · Replies 1 ·
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1

Graduate Inflation & Quasars energy and 'fast-forward effect' ?

  • pibara
  • · Replies 4 ·
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4