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

Undergrad Why is there no "mid-Atlantic ridge" on other planets?

  • Edward Barrow
  • · Replies 15 ·
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15

High School Can Dark Matter Explain Black Holes and the Mysterious Planet-Nine?

  • Physics_Kid
  • · Replies 73 ·
3
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73

High School How Difficult Will It Be to Remove Mars from the Planetary Protection Treaty?

  • lifeonmercury
  • · Replies 1 ·
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1

Stargazing Exposures & Stacking for DSLR Sky Photos

  • sophiecentaur
  • · Replies 26 ·
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26

Undergrad When Does the Radiation Epoch Begin with a Scale Factor of ~t1/2?

  • PeteSampras
  • · Replies 1 ·
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1

Undergrad Time & Cosmology: Observing Past Quantities & Effects on Equations

  • Arman777
  • · Replies 15 ·
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15

High School Background Radiation: Is It From Beyond Our Galaxy?

  • david graham
  • · Replies 10 ·
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10

Graduate Question About Moving Observers and Observable Universes

  • MassNerd
  • · Replies 2 ·
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2

High School Why does Sirius A blink in many colors?

  • parshyaa
  • · Replies 31 ·
2
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31

High School Everything is in motion, what is not?

  • starseeker
  • · Replies 12 ·
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12

High School Can Planets Thrive in Binary Star Systems?

  • lifeonmercury
  • · Replies 6 ·
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6

Graduate What keeps Rhea stable? Simulation shows Titan-assist escape

  • D O
  • · Replies 6 ·
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6

High School Formation of Stars: Questions on Range & Equilibrium

  • Brunolem33
  • · Replies 8 ·
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8

Stargazing The Sun from Pluto: Visibility & Brightness

  • grandpa2390
  • · Replies 4 ·
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4

Undergrad Friedmann Equation Analysis, expansion of the universe?

  • SmcWill
  • · Replies 3 ·
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3

Undergrad How is entropy defined for cosmological phenomena?

  • Stephen Tashi
  • · Replies 7 ·
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7

High School Is expansion the same Throughout the Universe

  • wolram
  • · Replies 8 ·
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8

Graduate Another detection of the 3.5 KeV line

  • phyzguy
  • · Replies 1 ·
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1

High School Is this Saturn photo real or an artist's rendition?

  • larry909
  • · Replies 9 ·
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9

Undergrad Evolution of the Energy Density Parameters

  • Jorrie
  • · Replies 19 ·
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19

Undergrad Discover the Latest Cosmological Parameters for the CDM Lambda Concordance Model

  • resurgance2001
  • · Replies 3 ·
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3

Undergrad Chaotic Inflation: Does it Involve Phase Transition?

  • Ranku
  • · Replies 6 ·
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6

Undergrad Integrating the Friedmann Equations

  • Trixie Mattel
  • · Replies 1 ·
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1

High School Is The Holographic Universe Theory Gaining Popularity And Why?

  • wolram
  • · Replies 23 ·
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23

Undergrad What is the Dipole Repeller and How Does it Affect Our Galaxy's Motion?

  • Shellsunde
  • · Replies 6 ·
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6

Undergrad Is momentum conserved in the entire observable universe?

  • Arman777
  • · Replies 22 ·
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22

Undergrad How can I have an image in space that I cannot reach out and feel with my hand?

  • barryj
  • · Replies 7 ·
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7

High School Could Jet Engines Be Used for Space Travel?

  • Borrah Campbell
  • · Replies 37 ·
2
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37

Undergrad Einstein & Lambda: 1917 Static Model Review

  • Chronos
  • · Replies 2 ·
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2

High School Where Can I Find a Barycentric Solar System Ephemeris?

  • Dale
  • · Replies 4 ·
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4

High School Visibility of Ceres, Uranus, and Neptune with $60 binoculars

  • lifeonmercury
  • · Replies 3 ·
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3

High School What Color Are Asteroids? Classification and Composition Explained

  • Albertgauss
  • · Replies 1 ·
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1

Undergrad Level of unseen elastic scatterings

  • snorkack
  • · Replies 6 ·
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6

Stargazing Formulas for camera obscura (correct sub forum?)

  • Ravensong
  • · Replies 3 ·
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3

Undergrad Is proton decay considered in neutron star models (and LHC)?

  • jarekduda
  • · Replies 16 ·
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16

High School On the post-main-sequence evolution

  • Singlau
  • · Replies 9 ·
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9

High School Is the universe expanding faster than expected

  • wolram
  • · Replies 4 ·
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4

High School Types of Supernovae: Explanations & Differences

  • SethUzumaki
  • · Replies 2 ·
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2

Graduate Energy scale of Hubble constant for dark energy scalar field

  • victorvmotti
  • · Replies 8 ·
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8

High School Calculating Distance: What Am I Doing Wrong?

  • Discman
  • · Replies 4 ·
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4

Undergrad Electroweak symmetry breaking and quantum tunneling.

  • Ranku
  • · Replies 12 ·
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12

High School Does the 2LOT rule out an eternal universe?

  • orion1977
  • · Replies 19 ·
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19

High School Mass and free fall speed under gravity

  • Orrin
  • · Replies 2 ·
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2

Graduate Lyman-alpha forest: why not Lyman-beta?

  • astrolollo
  • · Replies 5 ·
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5

Graduate Understanding the Relationship Between Inflation and Quantum Fluctuations

  • Quds Akbar
  • · Replies 1 ·
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1

High School Transit of newly discovered exoplanet of Proxima centuri

  • jordankonisky
  • · Replies 5 ·
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5

Undergrad What would it take to hear the Sun's sound from Earth?

  • Gerinski
  • · Replies 12 ·
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12

Undergrad Inflation and Gaussian CBR pertubations

  • Buzz Bloom
  • · Replies 4 ·
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4

High School What is the heaviest element that a star will fuse?

  • Aizen
  • · Replies 11 ·
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11

High School What would happen if the Moon wasn't there?

  • Adamchiv
  • · Replies 21 ·
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21

Graduate Q: Black hole event horizon vs distortion effects

  • Chris G
  • · Replies 8 ·
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8

High School How does Ram pressure kill galaxies

  • wolram
  • · Replies 6 ·
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6

Graduate Is linear polarization not expected from an astrophysical maser

  • TheCanadian
  • · Replies 6 ·
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6

Undergrad Different forms of energy density in inflation

  • shinobi20
  • · Replies 29 ·
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29

Undergrad Rescaling the equation of motion of inflation

  • shinobi20
  • · Replies 3 ·
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3

High School Redshift of distant galaxies....

  • Alistair Bingham
  • · Replies 4 ·
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4

High School Speed of light within a black hole

  • nettleton
  • · Replies 25 ·
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25

Graduate Throwing gravity and dark energy in the same basket

  • #Thomas#
  • · Replies 1 ·
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1

High School Venus -- a more attractive target than Mars for human colonization?

  • lifeonmercury
  • · Replies 10 ·
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10

High School Are There Constellations with Stars Close to Each Other?

  • lifeonmercury
  • · Replies 16 ·
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16

Undergrad Particle distribution as a function of radius in astrophysics

  • MMS
  • · Replies 3 ·
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3

Undergrad Are Finite Universe Models Plausible Despite Flat Curvature?

  • durant35
  • · Replies 2 ·
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2

Stargazing What sort of camera would you use?

  • BL4CKB0X97
  • · Replies 10 ·
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10

Undergrad Constraints on Dark Matter in the Solar System

  • Buzz Bloom
  • · Replies 14 ·
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14

Undergrad Can Spacetime be a Reference Frame?

  • Arman777
  • · Replies 23 ·
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23

Undergrad Why is the DM density near the sun so small?

  • Buzz Bloom
  • · Replies 2 ·
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2

Undergrad How Does the Lyman Break Drop-Out Technique Identify High Redshift Galaxies?

  • resurgance2001
  • · Replies 2 ·
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2

Undergrad How to know what proposal to write for observation?

  • Phys12
  • · Replies 1 ·
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1

High School Is the Universe Inside a Black Hole?

  • Will K
  • · Replies 28 ·
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28

High School Is the Big Bang Just an Event in an Existing Space/Time Fabric?

  • Physics_Kid
  • · Replies 1 ·
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1

Undergrad Growing food in space - a 3rd concept

  • Al_
  • · Replies 1 ·
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1

Undergrad Estimate the number of CMB photons in 0.25-litre

  • rano jojo
  • · Replies 6 ·
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6

High School Relating Gravitational Field Strength and Mass

  • taetae
  • · Replies 5 ·
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5

High School How would I calculate how much light is being bent in a certain area?

  • Verideth
  • · Replies 1 ·
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1

High School Top 3 candidates in our solar system to host microbial life from Earth

  • lifeonmercury
  • · Replies 6 ·
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6

Undergrad Which is better to colonize: Mars, the Moon, or Deimos?

  • Al_
  • · Replies 1 ·
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1

High School Why do black holes have infinite density, mass, and gravity?

  • science_rules
  • · Replies 9 ·
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9

Undergrad How Can Gravitational Lensing Help Detect Dark Energy?

  • Chronos
  • · Replies 3 ·
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3

Graduate Human Implications of Space Travel: A Psychological Exploration

  • houlahound
  • · Replies 8 ·
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8

Graduate Chandrasekhar Mass - White Dwarf

  • Leonardo Machado
  • · Replies 2 ·
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2

High School Keeping Time on Mars: A New Calendar System?

  • lifeonmercury
  • · Replies 9 ·
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9

High School Hot Jupiters & Kepler's Laws: Does it Violate?

  • jordankonisky
  • · Replies 4 ·
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4

Undergrad Where did the Dark Energy (or similar mechanism) come from?

  • Bolhuso
  • · Replies 4 ·
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4

Undergrad Question about "the big bang happened everywhere at once"

  • CaptDude
  • · Replies 14 ·
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14

High School Evolving Dark Energy: A Missed Revolution?

  • Chronos
  • · Replies 1 ·
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1

High School Is Our Brain Limiting Our Understanding of the Universe?

  • Simon Peach
  • · Replies 10 ·
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10

Undergrad Qs re dark matter when all baryonic matter is in black holes

  • Buzz Bloom
  • · Replies 18 ·
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18

Undergrad A multiple-impact origin for the Moon

  • Buzz Bloom
  • · Replies 3 ·
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3

Graduate Can white dwarfs have iron cores?

  • 21joanna12
  • · Replies 26 ·
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26

Undergrad Structure of Earth, pressure and density model

  • Jenab2
  • · Replies 2 ·
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2

Undergrad Unraveling the Mystery of Dark Matter: The Missing 96% of the Universe

  • Johnsmith123
  • · Replies 11 ·
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11

Undergrad What Is the True Nature of Dark Matter?

  • SD das
  • · Replies 3 ·
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3

Undergrad Is the Strange Star's Composition Similar to a Bose-Einstein Condensate?

  • FallenApple
  • · Replies 1 ·
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1

Undergrad How Can I Graph Hubble Term vs. Inflaton Using Mathematica?

  • shinobi20
  • · Replies 8 ·
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8

High School Dark matter can be cold warm or hot

  • wolram
  • · Replies 2 ·
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2

Undergrad Qs: What is known and known to be unknown about DM

  • Buzz Bloom
  • · Replies 14 ·
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14

Earth vs. Space Research: Which One Holds More Importance for Humanity?

  • houlahound
  • · Replies 7 ·
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7

High School New star in the skies -- Plausible?

  • lifeonmercury
  • · Replies 20 ·
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20

High School Problems With a Terraformed Moon -- Maybe?

  • Oomuu
  • · Replies 32 ·
2
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32

Graduate Starobinsky Inflation and Supergravity

  • Urs Schreiber
  • · Replies 10 ·
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10