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 What Causes the Phenomenon of Cosmic Inflation?

  • BadgerBadger92
  • · Replies 18 ·
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18

Graduate Zero-Energy Universe: Stephen Hawking Explains

  • Mircea Golumba
  • · Replies 19 ·
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19

High School What is the gravitational force like near a black hole?

  • Timothy Schablin
  • · Replies 5 ·
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5

Undergrad False vacuum and matter density

  • Ranku
  • · Replies 7 ·
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7

Undergrad Understanding the Ly-α Forest for EnSlavingBlair

  • EnSlavingBlair
  • · Replies 5 ·
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5

Undergrad Image of a Newly Formed Planet in a Disk Around a Star

  • BillTre
  • · Replies 3 ·
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3

Undergrad Particle acceleration and kinetic energy

  • spossatamente
  • · Replies 1 ·
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1

Stargazing Achieving Better Astrophotography at Home

  • sophiecentaur
  • · Replies 39 ·
2
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39

Graduate Is there a reason the Big Bang would be secret?

  • BadgerBadger92
  • · Replies 3 ·
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3

Graduate Is the Universe a Self-Similar Tesselation?

  • Jebediah Kerman
  • · Replies 29 ·
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29

Graduate What are the frontiers of cosmology research?

  • Avi Nandi
  • · Replies 9 ·
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9

Undergrad About gravitational binding energy and kinetic energy

  • GabrielLight
  • · Replies 11 ·
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11

Obituary of Constance Adams, Space Habitat Designer

  • BillTre
  • · Replies 1 ·
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1

Undergrad Is the Milky Way's halo curved spacetime?

  • tomwestboro
  • · Replies 1 ·
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1

High School Why do most of the celestial bodies rotate about their axis?

  • MeAndMyLucidLife
  • · Replies 10 ·
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10

Undergrad Inflation and density perturbations

  • Ranku
  • · Replies 2 ·
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2

High School Hubble’s Constant Changes Over Time

  • jedishrfu
  • · Replies 2 ·
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2

Undergrad Black hole vs mathematical singularity

  • LYCON
  • · Replies 2 ·
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2

High School Equivalent gravitational forces in other galaxies

  • jk22
  • · Replies 3 ·
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3

High School Oumuamua non-gravitational acceleration

  • TeethWhitener
  • · Replies 1 ·
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1

High School Lowest possible altitude for a Satellite

  • jms4
  • · Replies 32 ·
2
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32

High School Please explain to me the 2d holographic universe

  • empleat
  • · Replies 3 ·
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3

High School How large was the Universe at its moment of creation?

  • BadgerBadger92
  • · Replies 19 ·
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19

High School What is the role of a non-real observer in mathematical thinking?

  • Suekdccia
  • · Replies 1 ·
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1

Undergrad How on Earth This is possible? (distance to a far galaxy)

  • Prof Sabi
  • · Replies 4 ·
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4

Undergrad How stellar aberration was quantified in the early days

  • Gene Naden
  • · Replies 5 ·
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5

Undergrad Entropy and contracting universe

  • Schnellmann
  • · Replies 10 ·
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10

Undergrad Can Boltzmann Brains Form in an Infinite Universe?

  • DannyTr
  • · Replies 19 ·
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19

Undergrad If the Universe’s Mass was 100 At the Moment of the Big Bang....

  • Islam Hassan
  • · Replies 13 ·
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13

Undergrad How do we get stars so much more massive than the Sun?

  • zuz
  • · Replies 16 ·
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16

High School How does 400 sigma compare with 5 sigma?

  • Cerenkov
  • · Replies 17 ·
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17

High School Big Slurp: What Is It and How Does It Work?

  • LYCON
  • · Replies 1 ·
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1

High School History question -- The choice of the North Pole being up or down

  • Grinkle
  • · Replies 18 ·
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18

High School What Makes Red Dwarf Stars Cooler Than the Sun?

  • hyunxu
  • · Replies 44 ·
2
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44

High School Help with understanding a Friedmann flat universe

  • Cerenkov
  • · Replies 13 ·
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13

Undergrad Manned mission to Europa: science or still scifi?

  • Aidyan
  • · Replies 8 ·
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8

Undergrad How Does Angular Diameter Distance Apply to the Last Scattering Surface?

  • WeiShan Ng
  • · Replies 2 ·
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2

Undergrad 2 second delay at the merger of two neutron stars in August 2017

  • exponent137
  • · Replies 4 ·
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4

Undergrad Curve fitting the luminosity distance and redshift data

  • redtree
  • · Replies 5 ·
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5

Stargazing A good telescope with tracking for deep sky objects

  • kolleamm
  • · Replies 17 ·
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17

High School Could Gravitational Waves Allow for Time Travel?

  • yerty4235437y
  • · Replies 7 ·
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7

High School Does Negative Mass Impact Expansion in Vacuum Space?

  • yerty4235437y
  • · Replies 6 ·
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6

Undergrad Why was the early universe's entropy low?

  • Thecla
  • · Replies 1 ·
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1

High School What is the Speed of Light in Dark Matter?

  • Sanborn Chase
  • · Replies 29 ·
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29

Graduate Methane and Organic Molecules on Mars

  • BillTre
  • · Replies 18 ·
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18

Undergrad Does the barycenter of the Earth-Moon system change?

  • Sven E
  • · Replies 2 ·
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2

Undergrad Does the Uncertainty Principle imply a linear cosmology?

  • jcap
  • · Replies 3 ·
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3

Stargazing Could the 1841 Meteor in Puget Sound Be Something Else?

  • diogenesNY
  • · Replies 17 ·
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17

High School Is space is continuous or discrete?

  • Varsha Verma
  • · Replies 10 ·
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10

High School Do multiverses follow the same laws of physics?

  • kolleamm
  • · Replies 1 ·
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1

High School What is the speed of the Earth traveling through the cosmos?

  • john1800
  • · Replies 11 ·
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11

Stargazing How is noise removed in radio telescopes?

  • Phys12
  • · Replies 28 ·
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28

Undergrad Question about the Na-O anti correlation

  • crescentcavae
  • · Replies 1 ·
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1

High School Would planets fall out of orbit when gravity has a speed?

  • Erribert
  • · Replies 7 ·
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7

Undergrad What to do with unused space in a home freezer?

  • Richard Crane
  • · Replies 20 ·
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20

Stargazing What makes the Thirty Meter Telescope a game-changer for astronomy?

  • Chronos
  • · Replies 2 ·
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2

Undergrad Did NASA's Curiosity Rover Discover Ancient Organic Matter on Mars?

  • DrClaude
  • · Replies 2 ·
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2

Undergrad How many degrees / radians is one full orbit of the Earth?

  • Patrick Aberdeen
  • · Replies 8 ·
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8

High School Doesn't there have to be more than one observable universe?

  • platosuniverse
  • · Replies 41 ·
2
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41

Undergrad What does L star mean in the Schechter function?

  • I_laff
  • · Replies 3 ·
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3

Undergrad Are displaced dark matter and curved spacetime same thing?

  • Luke W
  • · Replies 12 ·
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12

Undergrad Big Bang Singularity: Was It As "Infinitely Dense" As We Think?

  • Ratman101
  • · Replies 35 ·
2
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35

Stargazing Spotting the ISS With My Binoculars: A Lucky Moment

  • Prof Sabi
  • · Replies 10 ·
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10

Undergrad Why Is the Velocity of an Oort Cloud Object Approximately Zero?

  • I_laff
  • · Replies 5 ·
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5

Undergrad Does red shift approach infinite near time zero?

  • DarkMattrHole
  • · Replies 14 ·
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14

Undergrad Where Did the Universe's Antimatter Go?

  • Pouya Pourkarim
  • · Replies 2 ·
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2

Undergrad How to check if stellar/galactic spectrum extraction went well?

  • SMBH
  • · Replies 3 ·
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3

High School Is there a way to measure gravity in a particular area of space

  • nuby
  • · Replies 14 ·
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14

Undergrad Galaxy with no dark matter? (NGC1052-DF2)

  • phinds
  • · Replies 108 ·
4
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108

High School Threshold of gravitational pull over dark energy

  • rede96
  • · Replies 66 ·
3
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66

High School LIGO's Detection of Gravitational Waves: BH-BH & BH-NS Mergers

  • wolram
  • · Replies 6 ·
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6

High School Calculating Weight and mass of entire black hole

  • hyunxu
  • · Replies 11 ·
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11

High School Spectroscopy of Stars: Electrons in Plasma

  • Sophrosyne
  • · Replies 4 ·
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4

Undergrad How is color added to Hubble images?

  • Phys12
  • · Replies 7 ·
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7

Undergrad Understanding 2012 VP113's Perihelion and Its Significance in Planetary Origins

  • fizzy
  • · Replies 1 ·
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1

High School Could a Black Hole Cause a Sunrise in the West?

  • Ashraf Siddiqui
  • · Replies 34 ·
2
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34

Undergrad Did astronomers just lengthen the expected life of the Sun by 5 Gy?

  • swampwiz
  • · Replies 5 ·
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5

High School Bubble universes and infinite in extent

  • laymanB
  • · Replies 28 ·
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28

Graduate Does a Quasar Have Proper Motion?

  • quasarLie
  • · Replies 22 ·
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22

Undergrad Have we measured the change in the red shift over time?

  • Justin Hunt
  • · Replies 3 ·
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3

High School The Future of the Universe: When Will It End?

  • Jimmy87
  • · Replies 28 ·
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28

Undergrad Perceived Speed of Objects in Space

  • krs1
  • · Replies 5 ·
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5

Stargazing What Causes the NEQ6 Pro Mount to Have 'Brain Failure' During Alignment?

  • sophiecentaur
  • · Replies 4 ·
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4

Undergrad V774104: Mysterious Sednoid with No Known Orbit

  • nikkkom
  • · Replies 8 ·
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8

Undergrad Conservation of Energy on the Cosmological Scale

  • Islam Hassan
  • · Replies 2 ·
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2

Undergrad Andromeda and the cosmological redshift

  • nmsurobert
  • · Replies 28 ·
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28

Stargazing Where did oxygen come from? Stars or something else?

  • Morlaf
  • · Replies 21 ·
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21

High School Photon mean free path (regarding CMB black body assumption)

  • bahamagreen
  • · Replies 7 ·
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7

Undergrad Relationship between stellar mass and core mass?

  • bbbl67
  • · Replies 7 ·
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7

Undergrad Frequency of nearby Supernova Explosions

  • windy miller
  • · Replies 13 ·
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13

Undergrad Atmospheric CO2 and diurnal Asymmetry

  • johnbbahm
  • · Replies 10 ·
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10

Undergrad How can I go about making a "Space Proof" coating?

  • Tech2025
  • · Replies 3 ·
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3

Undergrad Cosmological Redshift and Heisenberg Uncertainty Principle

  • e2m2a
  • · Replies 5 ·
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5

High School Did Astronomers Really Think the Milky Way Was the Only Galaxy in 1900?

  • Thecla
  • · Replies 8 ·
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8

Undergrad On gravity and the conservation of energy

  • Catreece
  • · Replies 30 ·
2
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30

Stargazing Zeiss Terra ED 10x42 Binos for stargazing?

  • Doc Al
  • · Replies 8 ·
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8

High School How Did the Big Bang Happen If the Speed of Light Is a Limit?

  • Gondur
  • · Replies 13 ·
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13

Undergrad SU(2) invariance implies isotropy?

  • JuanC97
  • · Replies 7 ·
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7

Graduate What are the typical uncertainties of data in Astophysics?

  • Fabioonier
  • · Replies 7 ·
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7

Graduate Multiverse reduction in the new Hawking/Hertog model?

  • Agrippa
  • · Replies 28 ·
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28