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

High School Space expanding or Time speeding up? Part 2

  • CosmologyHobbyist
  • · Replies 3 ·
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3

Graduate End of Inflation: Definition, Meaning & Models

  • Figaro
  • · Replies 12 ·
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12

High School Conservation of Energy and Expansion Redshift

  • John Morrell
  • · Replies 8 ·
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8

Undergrad Where on the Moon should the first Moonbase be?

  • Al_
  • · Replies 32 ·
2
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32

High School Is Jupiter's Great Red Spot Hiding a Massive Volcano?

  • CosmologyHobbyist
  • · Replies 1 ·
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1

Graduate What is the formula for calculating the Ascendant?

  • Jerky Jesse
  • · Replies 1 ·
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1

Undergrad Inflation, horizon-problem and thermal equilibrium

  • haushofer
  • · Replies 18 ·
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18

High School What do the letters in the solar sail equation denote?

  • Enis
  • · Replies 2 ·
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2

High School Is it possible to compress the space without gravity?

  • Sandip Kumar
  • · Replies 5 ·
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5

Undergrad How to embed the universe in R^4

  • Kontilera
  • · Replies 1 ·
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1

High School Edge of the Universe: Is It Real?

  • John Morrell
  • · Replies 6 ·
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6

High School Black hole mass and sigma (velocity dispersion)

  • Singlau
  • · Replies 5 ·
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5

Undergrad Spacetime Relativity: Universe Expansion & Our Place in It

  • Anujkumar
  • · Replies 21 ·
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21

High School The Best Spot to Set Up a Colony on Mars

  • lifeonmercury
  • · Replies 10 ·
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10

Undergrad Explain the orbital physics of the JAXA Tether experiment?

  • SteveO33
  • · Replies 77 ·
3
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77

Undergrad Would the rogue planet in this picture slow Earths spin?

  • Edward Barrow
  • · Replies 14 ·
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14

Graduate Space Radio Software: Get Help from Experts Now!

  • Shubham Jaydeokar
  • · Replies 2 ·
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2

Undergrad Carolo Rovelli on infinity in LQC

  • windy miller
  • · Replies 9 ·
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9

Undergrad Length of lunar month immediately after moon's formation?

  • Althistorybuff
  • · Replies 1 ·
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1

Undergrad Can a planet have multiple large moons?

  • Sherwood Botsford
  • · Replies 1 ·
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1

High School If the universe is expanding at an accelerating rate....

  • Colm
  • · Replies 3 ·
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3

High School How do we know the stars are not our own light falling back.

  • Colm
  • · Replies 4 ·
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4

Graduate How is the Trappist 1 system stable?

  • Sherwood Botsford
  • · Replies 6 ·
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6

Graduate Orbit Estimation: Range & Doppler Measurements for Position & Velocity

  • AT36
  • · Replies 3 ·
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3

Undergrad Mass and temperature relation in stars

  • jamespompey2109
  • · Replies 5 ·
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5

High School Question about Hertzsprung-Russell-diagram

  • Meerio
  • · Replies 2 ·
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2

Graduate Is the matter-antimatter annihilation observable in priciple

  • Gerinski
  • · Replies 1 ·
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1

Graduate Cosmological Redshift distance to where it begins?

  • rmpearlman
  • · Replies 5 ·
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5

Undergrad How Can I Improve My 2D Newtonian Gravity Simulator?

  • Ben S
  • · Replies 7 ·
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7

Undergrad Dragging a wormhole into a black hole

  • CA Mason
  • · Replies 7 ·
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7

High School Information paradox in black holes

  • Blue Scallop
  • · Replies 20 ·
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20

Undergrad Uncovering the Hidden Lepton Number of the Universe

  • snorkack
  • · Replies 1 ·
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1

Undergrad Clusters at center and periphery

  • nomadreid
  • · Replies 2 ·
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2

Undergrad What causes the deceleration of a satellite? Space dust?

  • Robert Scott
  • · Replies 4 ·
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4

Undergrad Probability of not entering de Sitter

  • durant35
  • · Replies 1 ·
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1

High School Is the Earth Really 4.5 Billion Years Old or Much Older?

  • geraud
  • · Replies 13 ·
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13

Undergrad Size and shape of a black hole singularity?

  • kris kaczmarczyk
  • · Replies 13 ·
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13

High School Is There an Arctic Circle on the Moon?

  • lifeonmercury
  • · Replies 1 ·
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1

High School How fast is Earth traveling due to the Hubble constant?

  • Nick Levinson
  • · Replies 43 ·
2
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43

Undergrad Will interstellar travel become more possible in future

  • Steven Hansel
  • · Replies 22 ·
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22

Undergrad On the Moon, could you melt dirt by focussing sunlight?

  • Al_
  • · Replies 1 ·
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1

Undergrad Why are Lagrange points called libration points, and....

  • nomadreid
  • · Replies 4 ·
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4

High School Are Black Holes linked to our Universe & Dark Energy/Matter?

  • HARVEYU1E1
  • · Replies 25 ·
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25

High School Simplistic question about mass and gravity

  • Noisy Rhysling
  • · Replies 15 ·
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15

Undergrad Big rip - order of distintegration?

  • janq
  • · Replies 1 ·
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1

High School Fine Tuning Constants: Understanding Variables and Ratios | Physics NIST

  • name123
  • · Replies 2 ·
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2

High School Could Microbes Really Thrive in the Clouds of Venus?

  • lifeonmercury
  • · Replies 12 ·
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12

High School Is Dark Matter in the 100GeV range

  • wolram
  • · Replies 2 ·
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2

High School What would happen to the Moon if (at full moon) the Earth disappeared?

  • lifeonmercury
  • · Replies 7 ·
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7

Graduate What Does Prof Krauss Mean About False Vacuum Decay and Cosmology?

  • Trollfaz
  • · Replies 8 ·
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8

High School How do you know the size/maximum area of a gravity field

  • Steven Hansel
  • · Replies 4 ·
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4

High School What are the applications of solar sails?

  • Enis
  • · Replies 1 ·
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1

Graduate Angular power spectrum, bias from N weighted events

  • ChristianS
  • · Replies 2 ·
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2

High School Need Martian Regolith/Soil Simulant. JSC Mars-1

  • jack h
  • · Replies 2 ·
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2

Undergrad Determining H value from scalefactor

  • JohnnyGui
  • · Replies 7 ·
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7

Undergrad Have you ever wondered why we can't see the other side of the moon?

  • akashpandey
  • · Replies 10 ·
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10

Undergrad Expanding universe and the Boltzmann brain problem

  • analyst5
  • · Replies 69 ·
3
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69

Undergrad Do Red Dwarfs Favor Rocky Planets and Host Life?

  • virgil1612
  • · Replies 4 ·
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4

Undergrad Why is it that Mercury rotates at a faster rate than say Pluto

  • Sean
  • · Replies 28 ·
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28

Undergrad Can we colonize the Kuiper Belt?

  • Al_
  • · Replies 11 ·
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11

High School Units for Entropy of Simple Black Holes

  • muzukashi suginaiyo
  • · Replies 3 ·
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3

Undergrad Gravitational waves as means for communication

  • Karlox
  • · Replies 5 ·
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5

High School What are the chances of evolution of organisms in space

  • mohau tshekoeng
  • · Replies 3 ·
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3

High School Cause of Inflation: Link to Dark Energy & Quintessence?

  • Tanelorn
  • · Replies 21 ·
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21

High School A question about an interesting article on dark matter

  • Tanelorn
  • · Replies 1 ·
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1

Graduate Observational evidence for accelerating universe

  • Gort
  • · Replies 2 ·
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2

Undergrad Shape of the universe -- Does it change with time?

  • MathematicalPhysicist
  • · Replies 27 ·
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27

Undergrad Do Event Horizons always contain a singularity?

  • FallenApple
  • · Replies 25 ·
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25

Undergrad How do we measure energy density of radiation?

  • binbagsss
  • · Replies 3 ·
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3

Undergrad What Evidence Exists for the Universe Before the Cosmic Microwave Background?

  • laymanB
  • · Replies 20 ·
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20

Undergrad Big Freeze and Law of convervation of energy

  • Rodrigo Olivera
  • · Replies 7 ·
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7

Undergrad Guarding Mars' atmosphere with a magnetic shield

  • infinitebubble
  • · Replies 24 ·
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24

Undergrad Effect of planetary layer densities on trajectories of a satellite

  • Tahmeed
  • · Replies 1 ·
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1

High School A Long Time Ago in a Galaxy Far....

  • mieral
  • · Replies 19 ·
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19

High School How can gravity act on a photon?

  • Simon Peach
  • · Replies 4 ·
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4

Undergrad Was There Another Dimension Shaping Time Before Our Known Dimension?

  • Fais
  • · Replies 6 ·
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6

High School Light Travel Time: Seeing the Past?

  • Bammitzcam
  • · Replies 6 ·
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6

High School Cosmological Redshift: Where Has the Energy Gone?

  • Glenn G
  • · Replies 3 ·
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3

High School Where Was Dark Energy Before the Accelerated Expansion Began?

  • mieral
  • · Replies 29 ·
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29

Stargazing What is the Explanation for the SECCHI Image of Object Opening a Shield?

  • infinitebubble
  • · Replies 4 ·
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4

High School What Saturn’s moon, Pan looks like

  • BillTre
  • · Replies 1 ·
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1

High School Exactly how quantum tunneling leads to a Big Bang?

  • Rodrigo Olivera
  • · Replies 29 ·
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29

Undergrad Could FRBs Power Extraterrestrial Light Sails?

  • jim mcnamara
  • · Replies 1 ·
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1

Graduate How can neutron stars have magnetospheres?

  • Cindy Hops
  • · Replies 6 ·
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6

Undergrad Q re early universe matter-antimatter annihilation

  • Buzz Bloom
  • · Replies 8 ·
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8

Graduate Neutron Star EoS: Find the Equation of State

  • Leonardo Machado
  • · Replies 3 ·
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3

Undergrad What is a Space-Time Crystal?

  • dvdt
  • · Replies 3 ·
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3

Undergrad Predicted sizes of (observable) universe

  • nomadreid
  • · Replies 13 ·
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13

High School What is the vacuum at the Karman line?

  • mesa
  • · Replies 1 ·
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1

High School What are the most likely ways of finding Dark Matter?

  • FelixH
  • · Replies 10 ·
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10

Graduate Space time expnasion, age of universe.

  • Lacplesis
  • · Replies 4 ·
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4

High School Is 200my enough for galaxies to form

  • wolram
  • · Replies 6 ·
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6

Undergrad Does Dark Energy drive up Entropy?

  • FallenApple
  • · Replies 7 ·
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7

High School Are black holes perfect spheres?

  • Alanay
  • · Replies 14 ·
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14

Graduate What is stochastic heating of very small grains?

  • sonutabitha
  • · Replies 2 ·
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2

High School The Center of the Milky Way Galaxy?

  • Goatman
  • · Replies 16 ·
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16

High School How Did the Universe Create Itself from Nothing?

  • babbane9
  • · Replies 5 ·
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5

High School How is the Horizon Drop Calculated Due to Earth's Curvature?

  • Axion
  • · Replies 2 ·
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2

High School Was there ever a state of nothingness?

  • thetexan
  • · Replies 5 ·
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5

Undergrad Software for Analysis of FITS table/spectra

  • SiuKing666
  • · Replies 11 ·
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11