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 Some questions related to the Cosmological Constant

  • Arman777
  • · Replies 4 ·
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4

Undergrad CMBR and the expansion history of the Universe

  • Ranku
  • · Replies 2 ·
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2

High School Are There Any Kardeshev 2.0 Civilizations in the Milky Way?

  • stefan r
  • · Replies 19 ·
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19

High School How well do we know solar activity?

  • Skiessa
  • · Replies 3 ·
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3

High School Milky Way is "in the top percentile of all the galaxies that exist"

  • CygnusX-1
  • · Replies 29 ·
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29

Undergrad What does the cosmic inflation theory actually say about flatness?

  • overzealous
  • · Replies 9 ·
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9

High School Name for the distribution of matter?

  • Brian Turner
  • · Replies 5 ·
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5

High School Structure and Dynamics of Blue Supergiants

  • lavinia
  • · Replies 2 ·
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2

High School Universe expansion rate in m/s^2 ?

  • roineust
  • · Replies 20 ·
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20

High School We see a quasar 13 billion light years away. What does this mean?

  • Skiessa
  • · Replies 4 ·
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4

Undergrad What is the new source of space radiation discovered near Earth?

  • davenn
  • · Replies 46 ·
2
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46

Undergrad Where does gravity switch from stronger to weaker, if it does?

  • freeelectron
  • · Replies 7 ·
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7

Graduate What Does Space Gives Moving Orders Mean for Gravity in Einstein's Universe?

  • Boballoo
  • · Replies 5 ·
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5

Undergrad Is Our Universe Finite or Infinite?

  • Ehyeh Asher Ehyeh
  • · Replies 9 ·
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9

Undergrad The Multiverse and 'No boundary' conditions approach in cosmology

  • Suekdccia
  • · Replies 3 ·
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3

High School Hip Replacements and Weather Sensitivity

  • wolram
  • · Replies 6 ·
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6

High School What Are the Force and Speed of Pulsar Winds?

  • Sundown444
  • · Replies 19 ·
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19

Undergrad Interpreting a scale factor vs. distance graph

  • naushaan
  • · Replies 13 ·
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13

Undergrad Separating Masses in Kepler's Third Law

  • KireeDendrall
  • · Replies 1 ·
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1

High School The search for habitable exoplanets in Alpha Centauri

  • alberto91
  • · Replies 2 ·
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2

Undergrad Confusion over what exactly constitutes the ecliptic

  • thebosonbreaker
  • · Replies 3 ·
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3

Undergrad Mass-luminosity relationship for red giants and AGB stars?

  • tovisonnenberg
  • · Replies 1 ·
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1

Graduate Are Retrograde Satellites the Key to Stable and Optimal Orbits?

  • mollwollfumble
  • · Replies 5 ·
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5

Undergrad Question about Galactic Rotation curves in the Milky Way galaxy

  • KurtLudwig
  • · Replies 14 ·
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14

Undergrad Was the Early Universe as Dense and Hot as a Neutron Star?

  • Greta
  • · Replies 24 ·
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24

Undergrad Calculating Speed and Acceleration of a Gas Blob Orbiting a Massive Black Hole

  • naushaan
  • · Replies 4 ·
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4

High School Question about the Sun's gravitational influence on the Earth and its moon

  • Evenlander
  • · Replies 8 ·
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8

Undergrad Would a rover on an asteroid float away because of the low gravity?

  • sciencec
  • · Replies 7 ·
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7

Undergrad Does Euclidean geometry require initial fine-tuning?

  • timmdeeg
  • · Replies 19 ·
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19

Undergrad How is asteroid 101955 Bennu possible?

  • alva3
  • · Replies 8 ·
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8

High School What is the shape of an asteroid impact on Earth?

  • Evenlander
  • · Replies 3 ·
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3

Friday's Historic All-Woman Spacewalk

  • Greg Bernhardt
  • · Replies 2 ·
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2

High School Creating an Interstellar Dust Nebula Experiment: Tips and Tricks for Success

  • angela6884
  • · Replies 13 ·
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13

Undergrad What happens to gravitational waves?

  • StandardsGuy
  • · Replies 28 ·
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28

Undergrad Lambda CDM Model and Spatial Flatness

  • timmdeeg
  • · Replies 26 ·
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26

Graduate Effects of gravity throughout space-time?

  • TrentonF
  • · Replies 6 ·
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6

Undergrad Travel from Mars to Earth question......

  • vicvalis
  • · Replies 10 ·
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10

Undergrad Maximum ##d_p(t_e)## value and its meaning

  • Arman777
  • · Replies 2 ·
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2

Undergrad How can black holes with varying masses have the same extreme characteristics?

  • Soul Intent
  • · Replies 10 ·
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10

High School Why does the Andromeda galaxy appear so tiny from our perspective?

  • Dnj23
  • · Replies 81 ·
3
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81

Undergrad Heating/cooling moon tunnels, why and how?

  • Fred Bobo
  • · Replies 16 ·
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16

High School Anyone here in the CA blackout area that has enjoyed dark skies?

  • swampwiz
  • · Replies 6 ·
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6

Undergrad Matter-Antimatter black hole collision

  • wheyghey
  • · Replies 4 ·
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4

Undergrad Hubble Law & SR: Does Velocity Increase Mass?

  • Arman777
  • · Replies 3 ·
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3

Undergrad Is this explanation of "space itself expanding" correct?

  • michelcolman
  • · Replies 27 ·
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27

Undergrad Are the red dots in the Whirlpool Galaxy individual red supergiants?

  • swampwiz
  • · Replies 2 ·
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2

Undergrad Scale factor from Friedmann's equations

  • TheMercury79
  • · Replies 7 ·
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7

Graduate Late Photons from the Early Universe?

  • Benzij
  • · Replies 1 ·
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1

High School What parameters of physics are most important to the existence of life?

  • Suppaman
  • · Replies 29 ·
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29

High School Nobel Prize for first exoplanet discovery

  • bland
  • · Replies 6 ·
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6

Graduate Why isn't back-reaction receiving more study?

  • phyzguy
  • · Replies 18 ·
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18

High School Atoms, Black Holes: Solving 2 Problems with 1 Theory?

  • tony169
  • · Replies 4 ·
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4

High School Angular Meteorite Strikes on the Moons Surface

  • Clay Gillespie
  • · Replies 2 ·
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2

Undergrad What is the current state of research on the nature of Time?

  • samudra
  • · Replies 13 ·
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13

Undergrad How to Assign Initial Conditions for Binary Star Systems in a Simulation?

  • Arman777
  • · Replies 2 ·
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2

High School What Happens to a Dead Galaxy's Mass?

  • brand1130
  • · Replies 15 ·
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15

Undergrad How Does Kirchoff's Law Relate to Spectrum Intensity and Wavelength?

  • SebastianRM
  • · Replies 8 ·
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8

Undergrad Hubble relation to Scale Factor

  • TheMercury79
  • · Replies 3 ·
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3

High School A question about the Planck Epoch

  • Quantum Alchemy
  • · Replies 1 ·
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1

High School Are Electrons & Protons Oriented in Stars Like Other Objects?

  • PhDnotForMe
  • · Replies 9 ·
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9

Undergrad Is Planet 9 Actually a Primordial Black Hole?

  • Tom.G
  • · Replies 6 ·
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6

Undergrad Cosmological scale and the pressure of light....

  • AshPowers
  • · Replies 6 ·
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6

Undergrad How does BBT resolve away from "It should be a black hole"

  • AshPowers
  • · Replies 2 ·
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2

Undergrad How can Kepler's laws be visualized using a simulator?

  • Riverplatense
  • · Replies 1 ·
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1

Undergrad Measuring Galactic Rotation: How & What We Know

  • PhDnotForMe
  • · Replies 5 ·
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5

Undergrad NASA's Black Hole Visualization/Explanation

  • BillTre
  • · Replies 13 ·
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13

Undergrad Does a beginning to time imply absolute speed?

  • Hiero
  • · Replies 8 ·
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8

High School Is there more to the Red Shift than we think?

  • jeffinbath
  • · Replies 18 ·
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18

Graduate What's the Difference Between Gravitational Waves and Gravity Waves?

  • math04
  • · Replies 1 ·
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1

Undergrad Could fundamental laws change in Dirac's Large Numbers Hypothesis?

  • Suekdccia
  • · Replies 1 ·
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1

High School Superclusters and their galaxies

  • Powehi
  • · Replies 3 ·
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3

Undergrad Cross Section of DM: What Are the Particle Candidates?

  • Arman777
  • · Replies 7 ·
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7

High School Expanding Space in the Lab: Investigating the Possibilities

  • Suppaman
  • · Replies 10 ·
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10

Possible to build a space tower?

  • skyshrimp
  • · Replies 28 ·
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28

Stargazing Who Tracks and Warns Us About Asteroids?

  • RetailPleb
  • · Replies 9 ·
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9

Anyone else thought the Moon last night was cool?

  • HankDorsett
  • · Replies 19 ·
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19

Undergrad Is J0740+6620 an eclipsing system?

  • GeorgeDishman
  • · Replies 2 ·
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2

Stargazing What explains the Luna impact gap?

  • Gfellow
  • · Replies 33 ·
2
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33

Undergrad Electricity & Planetary Magnetic Field Reversal: Implications & Studies

  • hiddenname
  • · Replies 20 ·
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20

Undergrad Could a Star Avoid a Supernova and Form a Black Hole?

  • Boca
  • · Replies 43 ·
2
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43

Undergrad Have I got the right picture for cosmological redshift?

  • George Keeling
  • · Replies 2 ·
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2

Graduate Stars: Light from the Past, End in Sight?

  • homerwho
  • · Replies 2 ·
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2

Undergrad Challenges to the Redshift Method and Hubble's Law

  • xhu2688
  • · Replies 5 ·
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5

High School What is the black that we see in the night sky?

  • Meruem
  • · Replies 13 ·
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13

High School How do we resolve the Boltzmann Brain problem

  • carl_sebastian
  • · Replies 36 ·
2
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36

High School How does the LIGO experiment affect SpaceTime?

  • physicsnoobie79
  • · Replies 7 ·
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7

Undergrad Large Bipolar radio bubbles in the Galactic Centre

  • Buzz Bloom
  • · Replies 1 ·
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1

High School A wormhole collides with a black hole -- what would happen?

  • Brianok
  • · Replies 4 ·
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4

High School Questions about the Timeline of the Big Bang

  • Cerenkov
  • · Replies 32 ·
2
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32

High School Do we have another interstellar visitor?

  • Ophiolite
  • · Replies 2 ·
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2

Undergrad Would we ever be able to fully understand the laws of the universe?

  • Delta2
  • · Replies 3 ·
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3

High School Can We See Our Past? - Milky Way & Hubble Telescope

  • Viopia
  • · Replies 69 ·
3
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69

Graduate Implications of Symmetry and Pressure in Friedmann Cosmology

  • PeterDonis
  • · Replies 2 ·
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2

Undergrad Question about stellar nucleosynthesis from a non-expert

  • CPW
  • · Replies 8 ·
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8

High School Can we observe anything beyond the CMB 'wall'?

  • Cerenkov
  • · Replies 5 ·
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5

High School Early Predictions of Hot Big Bang CMB: Gamov & Alpher

  • windy miller
  • · Replies 15 ·
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15

Venera 13 photos from the surface of Venus

  • ElliotSmith
  • · Replies 3 ·
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3

Stargazing What is the brightest red dwarf star seen from the Earth?

  • Cerenkov
  • · Replies 10 ·
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10

High School What would it be like on Earth if it were not a sphere?

  • AZFIREBALL
  • · Replies 42 ·
2
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42

Undergrad Is the Big Bang Actually a White Hole?

  • rootone
  • · Replies 22 ·
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22