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 Using stars random distribution to determine presence of gravity

  • tmh556
  • · Replies 3 ·
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3

Graduate Are Spiral Galaxies Truly Spirals or Just an Optical Illusion?

  • abitdim
  • · Replies 9 ·
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9

Undergrad Questions about Black Holes: Can Objects Survive? Can Light Go Through?

  • RustyBullet
  • · Replies 12 ·
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12

Graduate Does the Big Bang Model Support Instantaneous Inflation in an Infinite Universe?

  • SW VandeCarr
  • · Replies 16 ·
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16

Graduate Orbital period decay and gravitational waves

  • Ranku
  • · Replies 15 ·
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15

Graduate Space Elevator: Carbon Nanotubes, Lasers & Beamed Energy

  • danlgarmstron
  • · Replies 9 ·
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9

Undergrad Converting Intensity into magnitudes

  • lavenderblue
  • · Replies 1 ·
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1

Graduate What is the relationship between information and consciousness in the universe?

  • WaveJumper
  • · Replies 1 ·
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1

Graduate Neutron Star Collisions: Effects & Stages

  • josh_c7
  • · Replies 9 ·
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9

Graduate Revisiting the Big Bang: Galaxy HUDF-JD2

  • roland
  • · Replies 10 ·
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10

Graduate Hartle-Hawking Model (How the Universe Can Appear From Nothing)

  • TimBowe
  • · Replies 15 ·
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15

High School One question [size of the universe]

  • mtasquared
  • · Replies 22 ·
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22

Stargazing What is the bottom limit of telescopes and why can't they detect visible light?

  • aster79
  • · Replies 2 ·
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2

Undergrad Can Black Holes Consume the Entire Universe?

  • Aeronaut
  • · Replies 2 ·
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2

Graduate Does the Universe's Expansion Affect Time Travel?

  • anvesh111
  • · Replies 9 ·
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9

Graduate Hubble Ultra Deep Field baby galaxy examination

  • aib
  • · Replies 7 ·
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7

Graduate Nearby supernova risk discussed by Sigurdsson

  • marcus
  • · Replies 9 ·
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9

Graduate T Pyxidis Supernova: Energy Release Compared to SN1054

  • mheslep
  • · Replies 2 ·
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2

Graduate Why is the dark matter: baryonic matter ratio about 5:1?

  • BillSaltLake
  • · Replies 8 ·
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8

Graduate Orbital period decay and gravitational waves

  • Ranku
  • · Replies 5 ·
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5

Graduate Understanding the Limits of the Universe

  • RemoteSensor
  • · Replies 2 ·
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2

High School Is the Universe Expanding Without Boundaries?

  • ssope
  • · Replies 9 ·
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9

Graduate Current CMB photon number density?

  • denseguy
  • · Replies 1 ·
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1

High School Does the moon cause the flux and reflux of the tides?

  • BogMonkey
  • · Replies 6 ·
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6

Undergrad How Do We Measure the Size of the Universe?

  • paweld
  • · Replies 6 ·
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6

Graduate Effects of Magnetic fiedon the Dark Energy and Cosmic String

  • pieas
  • · Replies 1 ·
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1

Graduate Gravity on the surface of Gliese 581 d

  • horseshoe7
  • · Replies 19 ·
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19

High School How did universe start to expand

  • crazco
  • · Replies 9 ·
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9

Fermi Telescope Spots Giant Explosion in Space

  • Saturni
  • · Replies 21 ·
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21

Graduate How to calculate r.m.s radius of a N-body system?

  • luxiaolei
  • · Replies 1 ·
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1

High School If the universe is infinite, does it mean that everything exists?

  • Richard87
  • · Replies 24 ·
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24

Graduate Are Hubble's Sphere and the Universe's Age Coincidentally Similar?

  • zeromodz
  • · Replies 21 ·
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21

Graduate Do black holes evaporate or go bang ?

  • jimw
  • · Replies 31 ·
2
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31

High School See the Diffraction of Moon Light at Night

  • pmehnati
  • · Replies 3 ·
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3

Undergrad Inflation - can someone please explain it?

  • edpell
  • · Replies 28 ·
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28

High School Paper on the physics of big bang: what should be included

  • crazco
  • · Replies 5 ·
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5

Graduate Shouldn't All Black Holes Have EM Wave Halos?

  • jobyts
  • · Replies 1 ·
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1

Possible misenterpretations of the known universe

  • MrModesty
  • · Replies 3 ·
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3

Graduate A giganitc wavefuntion of the universe = determinism?

  • roberto85
  • · Replies 15 ·
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15

Graduate What Are the Biggest Mysteries of the Universe and How Can We Understand Them?

  • Sententia
  • · Replies 2 ·
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2

Graduate Cellular phones and reverse SETI

  • Robot B9
  • · Replies 9 ·
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9

Graduate Is a flat universe better imagined as an expanding sphere or a cube?

  • Holocene
  • · Replies 20 ·
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20

Graduate What Is the Physics Behind the Expansion of Space?

  • edpell
  • · Replies 17 ·
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17

What Are the Different Theories on the Creation of Our Universe?

  • jessicadambra
  • · Replies 1 ·
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1

Graduate Understanding Magnitude Systems in Extragalactic Imaging

  • ian2012
  • · Replies 1 ·
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1

Graduate Producing a CCD Image: Corrections, Calibration, Subexposures

  • ian2012
  • · Replies 2 ·
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2

High School What is the Direction of Orbiting Planets around the Sun?

  • albert1993
  • · Replies 1 ·
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1

Graduate Distinguishing between flatness

  • Ranku
  • · Replies 12 ·
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12

Graduate De Sitter universe, is it compatible with darkenergy?

  • hurk4
  • · Replies 7 ·
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7

Graduate If Hubbles constant is decreasing?

  • iidartzii
  • · Replies 10 ·
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10

Graduate Does any model predict the mass (or total energy) of the observable Universe?

  • BillSaltLake
  • · Replies 13 ·
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13

Graduate Variation of Density Parameters with Redshift

  • cepheid
  • · Replies 4 ·
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4

Graduate Accelerating Expansion: Is there a Positive Feedback Loop?

  • edpell
  • · Replies 1 ·
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1

Graduate Universe expanding or time speeding up?

  • CosmologyHobbyist
  • · Replies 18 ·
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18

Graduate Potential Vacuum Energy: Does it Double Every 11B Years?

  • Rubix
  • · Replies 7 ·
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7

Graduate Cosmological constant or dark energy or vaccum denisty/energy/energy density

  • edpell
  • · Replies 9 ·
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9

Graduate Confused about the event horizon

  • Paul_Bartosik
  • · Replies 7 ·
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7

Graduate Is Space-Time Really a Woven Fabric?

  • Darkroman
  • · Replies 6 ·
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6

Graduate Thermodynamics in Friedman World Models

  • cepheid
  • · Replies 2 ·
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2

Graduate Expansion of space and looking back in time

  • DARKSYDE
  • · Replies 7 ·
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7

Graduate Could dark energy have existed before the Big Bang?

  • hurk4
  • · Replies 17 ·
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17

Graduate Big Bang Expansion: White Hole Theory

  • DaneBramage
  • · Replies 8 ·
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8

Undergrad How to calculate the orbit of a minor planet?

  • neptunecs
  • · Replies 2 ·
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2

Undergrad Why Do Some Galaxies Have Warped Structures?

  • Astronuc
  • · Replies 5 ·
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5

Undergrad Why has no one seen Neptune with the naked eye?

  • Count Iblis
  • · Replies 5 ·
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5

Undergrad Is dark matter hiding in plain sight?

  • mintparasol
  • · Replies 38 ·
2
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38

Graduate Is the Inertial Frame Defined by the Universe's Center of Mass Unique?

  • edpell
  • · Replies 5 ·
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5

Fat Guy vs Skinny Guy: Universe Size Dependent?

  • beeresearch
  • · Replies 1 ·
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1

Undergrad Does Gravity Affect Nuclear Reactions in Space?

  • comsat
  • · Replies 5 ·
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5

Graduate The Conundrum of the Speed of Light and the Expanding Universe

  • Emu
  • · Replies 4 ·
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4

Undergrad Edge of Universe: What's Beyond the Limit?

  • um0123
  • · Replies 27 ·
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27

Undergrad Question about expanding universe VS gravity pull.

  • Cloengaa
  • · Replies 3 ·
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3

Undergrad Are LMC, SMC approaching the Milky Way ?

  • Widdekind
  • · Replies 2 ·
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2

Undergrad Qualifying Radiation Detectors for Space: Homework Help Needed

  • parazit
  • · Replies 2 ·
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2

Graduate Why does gravity cause lower orbit speed at smaller radii?

  • Bjarne
  • · Replies 18 ·
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18

Graduate Evidence for pre Big Bang physical universe?

  • Tiapan
  • · Replies 31 ·
2
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31

Undergrad Death of Mars: How a Volcano Could Trigger Planetary Extinction

  • MarsWTF
  • · Replies 2 ·
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2

Undergrad Calculating Kinetic Energy for Rotating Planets

  • Bjarne
  • · Replies 5 ·
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5

Stargazing My New Telescope - Review and EP Advice

  • Codester09
  • · Replies 1 ·
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1

High School Is a Used Telescope a Good Choice for a Beginner Astronomer?

  • bassplayer142
  • · Replies 5 ·
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5

Graduate Why are blue-shifted galaxies concentrated in specific sky directions?

  • Paulanddiw
  • · Replies 19 ·
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19

Undergrad What is the true scope of our universe?

  • nates
  • · Replies 5 ·
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5

Graduate The metric expansion of the Universe

  • espen180
  • · Replies 1 ·
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1

Graduate Mercury's Orbital Precession Anomaly

  • Bjarne
  • · Replies 1 ·
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1

High School WR104 Gamma Ray Burst: Fact or Fiction?

  • DR13
  • · Replies 1 ·
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1

Undergrad Astronomers use earth-based spectroscopy

  • AdkinsJr
  • · Replies 4 ·
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4

Is Nibiru Really Going to Collide with Earth in 2012?

  • The_Absolute
  • · Replies 5 ·
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5

High School Will the Moon escape Earth's orbit in billions of years?

  • Richard87
  • · Replies 8 ·
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8

Graduate What is the true essence of the universe beyond human perception?

  • Tommahawk
  • · Replies 3 ·
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3

Graduate Why is the term 'Big Bang' a misnomer?

  • Richard87
  • · Replies 4 ·
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4

Graduate How to Calculate the Scale of Venus's Atmosphere Using the Barometer Equation

  • Unto
  • · Replies 3 ·
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3

Undergrad Calculate Aphelion Distance & Velocity of Comet at Perihelion

  • Unto
  • · Replies 8 ·
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8

Graduate What Is the Temperature Differential of Hawking Radiation?

  • Ranku
  • · Replies 8 ·
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8

Undergrad Is There a Massive Time-Image Gap in Observing Distant Galaxies?

  • Eden27
  • · Replies 2 ·
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2

Undergrad What Causes Pluto's Elliptical Orbit Around the Sun?

  • jadunne
  • · Replies 3 ·
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3

High School Was there more than one Big Bang?

  • Krasimir
  • · Replies 9 ·
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9

High School Are Quasars Still Present in Our Universe?

  • Richard87
  • · Replies 3 ·
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3

Graduate How Does the Integrated Sachs-Wolfe Effect Support the Concept of Dark Energy?

  • cbd1
  • · Replies 4 ·
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4

Graduate Cephid Variables: Finding Distance from Parallax & Magnitude

  • Unto
  • · Replies 4 ·
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4

Graduate What Would an Infinite Universe Look Like at the Time of the Big Bang?

  • Backwoods
  • · Replies 6 ·
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6