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 Challenging the Big Bang: Addressing Objections to the Expanding Universe Theory

  • dm4b
  • · Replies 13 ·
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13

Graduate Redshift at 11.9 and the Hubble Constant

  • phtdegroot
  • · Replies 11 ·
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11

Graduate Is it wrong to see the bang as insertion of space?

  • negativzero
  • · Replies 8 ·
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8

Undergrad Are there any large star databases containing mass and density?

  • Xilor
  • · Replies 4 ·
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4

Graduate What is the TSS Engine and how can it enhance space-related learning?

  • Kirennian
  • · Replies 6 ·
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6

Graduate How can we say star mass affects event horizon diameter ?

  • PhyHunter
  • · Replies 5 ·
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5

Graduate Cosmological redshift, how fast can the universe expand?

  • P.Bo
  • · Replies 16 ·
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16

Graduate Given expansion, finally each particle will have only 1 neighbor

  • negativzero
  • · Replies 10 ·
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10

Graduate Why Stephen Hawking says universe can create itself from nothing?

  • big_bounce
  • · Replies 81 ·
3
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81

Graduate Singularity Paradoxes: Nothing or Something?

  • jerryboy
  • · Replies 4 ·
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4

Undergrad What Is Space in Physics?

  • tolove
  • · Replies 30 ·
2
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30

Graduate Did Quasars Play a Role in the Formation of Galaxies?

  • SpiderET
  • · Replies 17 ·
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17

Conspiratorial cosmology - the case against the Universe

  • Garth
  • · Replies 1 ·
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1

Undergrad The time it takes the Earth to go around the Sun.

  • Jimmy B
  • · Replies 49 ·
2
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49

Graduate When Will the Big Crunch Happen According to Current Models?

  • Devils
  • · Replies 37 ·
2
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37

Undergrad Why are Cosmic Rays and Hard X-rays Essential for Heating Molecular Clouds?

  • vikasagartha
  • · Replies 2 ·
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2

Redshift FAQ article development

  • Mordred
  • · Replies 142 ·
5
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142

Graduate Is Inflation the Key to Understanding a Flat Universe?

  • HowardTheDuck
  • · Replies 12 ·
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12

Undergrad How big was the Universe 13 billion years ago?

  • Endervhar
  • · Replies 41 ·
2
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41

Graduate Energy has mass & therefore gravity. Yet dark energy is repulsive ?

  • Robin
  • · Replies 5 ·
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5

High School The Earth-Sun Relationship: A Matter of Perspective

  • jackoblacko
  • · Replies 91 ·
4
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91

Graduate HR diagram: magnitude - luminosity relation

  • stargazer3
  • · Replies 3 ·
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3

High School How does the sun burn without oxygen?

  • Anna Blanksch
  • · Replies 5 ·
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5

Graduate Gravitational Acceleration Differences in a Pulsar: Calculation and Comparison

  • wcase
  • · Replies 4 ·
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4

Graduate Decent papers/articles on black holes

  • abhiroop_k
  • · Replies 4 ·
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4

Graduate Trying to understand the oscillation of electrons in the magnetic fiel

  • hb1547
  • · Replies 5 ·
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5

Graduate How did the CMB Lorentz frame get chosen?

  • Sam_Playle
  • · Replies 5 ·
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5

Graduate Does the boundary of the causal universe function as an event horizon?

  • benlittle
  • · Replies 18 ·
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18

Undergrad Cosmological constant calculation

  • ftr
  • · Replies 5 ·
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5

Graduate Higgs/vacuum stability and the universe

  • skydivephil
  • · Replies 2 ·
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2

Graduate Understanding the Nature of WIMPS: Bosons or Fermions?

  • snorkack
  • · Replies 1 ·
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1

Graduate Definiton of Schwarzschild radius clarification request

  • liometopum
  • · Replies 2 ·
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2

Undergrad How should I see the CMB picture

  • the_pulp
  • · Replies 3 ·
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3

Graduate A Gravitational Entropy proposal from Ellis, Tavakol, and Clifton

  • marcus
  • · Replies 1 ·
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1

Graduate Problems with living outside the Heliosphere?

  • StrayCatalyst
  • · Replies 1 ·
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1

Graduate Possible reason for dark energy (?)

  • jacjac
  • · Replies 16 ·
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16

Graduate What slowed or stopped inflation?

  • abbott287
  • · Replies 15 ·
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15

Graduate Article on New Planck Satellite data

  • Naty1
  • · Replies 20 ·
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20

Graduate Composition of the Universe can be Derived from PI?

  • zeroace
  • · Replies 21 ·
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21

Undergrad Life in Universe: Is Intelligent Life Inevitable?

  • Whateverworks
  • · Replies 91 ·
4
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91

Interesting facts about the Universe

  • 42Physics
  • · Replies 1 ·
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1

Stargazing New cosmic model parameters from South Pole Telescope

  • marcus
  • · Replies 35 ·
2
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35

Undergrad Can anything truly be stationary in our constantly moving universe?

  • shinnsohai
  • · Replies 3 ·
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3

Graduate A history of the universe using the new Planck numbers

  • marcus
  • · Replies 1 ·
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1

Graduate How Does a Comet's Path Relate to Relativity and Spacetime?

  • enceladus_
  • · Replies 9 ·
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9

Undergrad What Are the Fastest Moving Objects in the Universe?

  • EskWIRED
  • · Replies 11 ·
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11

Graduate Where in the universe am I absolutely still ?

  • fivetide
  • · Replies 5 ·
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5

Graduate How Does Particle Size Influence Emissivity in Circumstellar Dust?

  • robotopia
  • · Replies 4 ·
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4

Graduate Large Scale anomaly in Planck data

  • skydivephil
  • · Replies 11 ·
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11

Graduate Is Wikipedia's Explanation of Olber's Paradox Misleading?

  • HowardTheDuck
  • · Replies 14 ·
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14

High School From where did our earth get its initial velocity ?

  • Sab95
  • · Replies 7 ·
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7

Undergrad Best tables for data of objects in our solar system?

  • Elecomputer
  • · Replies 3 ·
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3

Graduate The Higgs mechanism and the Beginning of the Universe

  • Paulibus
  • · Replies 22 ·
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22

Graduate Planck Mission Reveals Universe Features: String Theory Hits

  • Chronos
  • · Replies 5 ·
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5

Graduate Inflation of singularity at moment of evaporation?

  • jks067
  • · Replies 9 ·
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9

What Exciting Discoveries Will the Live Planck Results Reveal?

  • skydivephil
  • · Replies 10 ·
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10

Undergrad Mystery of the Pushed Away Black Hole

  • huhjinsoo
  • · Replies 7 ·
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7

Undergrad Exploring the Habitable Zone: Limits and Possibilities for Detecting Alien Life

  • willstaruss22
  • · Replies 26 ·
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26

Undergrad Evolution of a star from a nebula

  • Sab95
  • · Replies 1 ·
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1

Graduate Is the universe large and finite, or infinite?

  • Luciano Kurban
  • · Replies 2 ·
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2

Graduate How can the universe be infinite, if it has a finite age?

  • Thomas1989
  • · Replies 1 ·
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1

Graduate On the formation of larger bodies in space after dust attraction.

  • Novawatcher
  • · Replies 2 ·
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2

Graduate What is a Vacuum in General Relativity?

  • Brook
  • · Replies 8 ·
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8

Graduate Understanding Magnetars and Neutron Stars

  • serp777
  • · Replies 11 ·
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11

Graduate Neutron Stars: Quantum or Classical Objects?

  • Raghnar
  • · Replies 2 ·
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2

Graduate Questions about nuclear physics inside a star

  • aeonflux
  • · Replies 13 ·
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13

Undergrad Gravitation as answer to whether the Universe is infinite?

  • ojbway
  • · Replies 3 ·
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3

Undergrad Interpreting Gravitational Lensing Images?

  • solarblast
  • · Replies 2 ·
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2

Undergrad Time Space Matter Characteristics

  • grendizer1
  • · Replies 3 ·
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3

Graduate What would happen if a black hole sucked in a cloud of hydrogen gas?

  • Crazymechanic
  • · Replies 15 ·
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15

Undergrad Can Planetary Gravity Flatten an Egg-Shaped Planet?

  • jaydnul
  • · Replies 9 ·
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9

Graduate Is Dark Matter Absorbing Photons and Emitting Undetectable Radiation?

  • rp1220
  • · Replies 3 ·
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3

Graduate Differences between polarisations and temperature anisotropies in the

  • pleasehelpmeno
  • · Replies 1 ·
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1

Graduate History of speed of the expansion of the universe?

  • SpaceBear
  • · Replies 4 ·
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4

High School Looking for some good websites for Physics and Cosmology

  • 42Physics
  • · Replies 3 ·
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3

Graduate What speed do quasars eject matter out the galaxy?

  • Teslanumber1
  • · Replies 8 ·
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8

Photo of Jupiter's moons with cellphone

  • Gliese123
  • · Replies 39 ·
2
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39

Graduate Do Black Holes *actually* exist?

  • Zelyucha
  • · Replies 43 ·
2
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43

Graduate Could the LHC potentially form a black hole?

  • PhysicsWanabe
  • · Replies 2 ·
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2

Undergrad Near earth Asteroids and a space elevator

  • Paintjunkie
  • · Replies 2 ·
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2

Graduate Normal&good question about redshift

  • marcus
  • · Replies 8 ·
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8

Graduate Could the universe just be a piece of something bigger?

  • marshallmeyer1
  • · Replies 13 ·
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13

Graduate Is dark energy or dark matter created to keep the Cosmological constant

  • arunshanker
  • · Replies 3 ·
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3

Graduate Evidence of Dark Matter within the Solar System?

  • greswd
  • · Replies 30 ·
2
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30

Graduate Questions about Nuclear Fusion in the Sun

  • enceladus_
  • · Replies 9 ·
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9

Graduate Gravitational Waves: Cosmic Inflation Equation

  • pleasehelpmeno
  • · Replies 11 ·
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11

Graduate How to calculate orbitals of celestial bodies using calculus?

  • eNathan
  • · Replies 1 ·
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1

Compiling Common Star Names for FK5 - Help Needed!

  • Scott S
  • · Replies 1 ·
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1

Graduate Can We Really Understand Black Holes If Nothing Can Escape Them?

  • E=mc4
  • · Replies 14 ·
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14

Stargazing Telescopes 101: Intro Guide For Beginners Under $500

  • NATURE.M
  • · Replies 15 ·
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15

Graduate Is the big bang singularity really a rapid expansion of spacetime?

  • Apophenia
  • · Replies 11 ·
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11

Graduate Can we expect stars to become visible only in infrared after a while?

  • SpaceBear
  • · Replies 3 ·
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3

Graduate Does Matter Truly Occupy Space or is it Merely Energy in a Certain State?

  • big_bounce
  • · Replies 2 ·
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2

Graduate For how long the Cosmic Microwave Background was emitted?

  • SpaceBear
  • · Replies 1 ·
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1

Graduate Can Gravity Act Faster Than Light?

  • arunshanker
  • · Replies 2 ·
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2

Graduate Rethinking Cosmology (Steinhardt)

  • marcus
  • · Replies 27 ·
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27

High School Why are we crashing with Andromeda?

  • McCartney
  • · Replies 20 ·
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20

Graduate Dark Energy Confusion - Unraveling the Mystery

  • HowardTheDuck
  • · Replies 12 ·
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12

Graduate Poincaré recurrence and maximum entropy

  • cryptist
  • · Replies 4 ·
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4

Graduate Why is Mars so easily visible to the naked eye?

  • Solon
  • · Replies 8 ·
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8