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 Dark matter can be cold warm or hot

  • wolram
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2

Undergrad What is known about dark matter distribution in galaxies?

  • Buzz Bloom
  • · Replies 14 ·
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14

Should humanity prioritize Earth research or space research?

  • 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

Undergrad Can black holes explain dark matter?

  • SD das
  • · Replies 2 ·
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2

Undergrad Gravitic Field of Rotating Disk-Shaped Mass Along Ecliptic

  • havonasun
  • · Replies 3 ·
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3

Stargazing How Can a Grain of Sand Create a Bright Meteor?

  • megacal
  • · Replies 80 ·
3
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80

Undergrad Effort to get us all on the same page (balloon analogy)

  • marcus
  • · Replies 548 ·
19
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548

High School Is dark matter self-interacting?

  • wolram
  • · Replies 20 ·
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20

High School Significance of a planet's "surface gravity"

  • lifeonmercury
  • · Replies 1 ·
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1

High School Move vehicle in space by rail structure systema

  • Juuso
  • · Replies 10 ·
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10

High School Time dilation on a spaceship traveling at 99.99% the speed of light

  • lifeonmercury
  • · Replies 26 ·
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26

High School Is the Earth in its original orbit?

  • scincemaniac
  • · Replies 11 ·
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11

Undergrad What is the Role of Space in this Apparatus?

  • GrantSB
  • · Replies 1 ·
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1

Undergrad Do cosmological models exclude Boltzmann brains as physical impossibilities?

  • durant35
  • · Replies 24 ·
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24

Stargazing Nebulosity is a hard program for the aged?

  • sophiecentaur
  • · Replies 7 ·
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7

High School B Calculating the age of the universe with the Hubble constant

  • anonymous24
  • · Replies 8 ·
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8

Undergrad Cosmological electroweak phase transition

  • Carlos L. Janer
  • · Replies 22 ·
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22

High School How do we observe black holes moving if time stops near them?

  • Jacob Gable
  • · Replies 7 ·
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7

Undergrad Galaxy Merger and Damped Oscillation?

  • FallenApple
  • · Replies 2 ·
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2

High School What is your favorite planet of the solar system?

  • bellocchiocarmel
  • · Replies 16 ·
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16

Undergrad What observation shows galaxies are in steady state circular motion?

  • Csmith
  • · Replies 17 ·
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17

High School If Earth moves at 500,000 mph then why don't satellites stay behind?

  • IsItSo
  • · Replies 18 ·
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18

Undergrad Has anything in the universe ever reached 0 Kelvin?

  • Remon
  • · Replies 16 ·
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16

Undergrad Is the fabric of space a "medium" for light?

  • GrantSB
  • · Replies 3 ·
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3

Undergrad Is angular momentum conserved in a Supernova?

  • FallenApple
  • · Replies 2 ·
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2

Undergrad How to solve for the volume of the universe / redshift

  • rano jojo
  • · Replies 11 ·
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11

Undergrad Can 21 cm Emission Be Detected in a Laboratory?

  • amarante
  • · Replies 2 ·
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2

High School How does gravity emerge from information in quantum systems?

  • wolram
  • · Replies 4 ·
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4

High School Is all the energy from the big bang still conserved?

  • ChrisisC
  • · Replies 15 ·
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15

High School What is the Relation Between Jeans Mass and Fundamental Mode in Acoustic Waves?

  • Discman
  • · Replies 12 ·
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12

Graduate Why isn't the pull of gravity neutral on large scales?

  • rede96
  • · Replies 34 ·
2
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34

High School Questions about the origin and evolution of dark energy.

  • K. Doc Holiday
  • · Replies 8 ·
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8

High School How can a physical entity be infinite?

  • Chris Miller
  • · Replies 28 ·
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28

High School What Do Scientists Think a Black Hole Is?

  • wolram
  • · Replies 23 ·
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23

High School Is the Universe infinite or not?

  • Robertphysics
  • · Replies 38 ·
2
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38

High School Does dark matter make black holes bigger?

  • adolphysics
  • · Replies 11 ·
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11

Undergrad Can we measure time without reference to entropy?

  • windy miller
  • · Replies 22 ·
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22

High School Are OH molecules in masers ionized?

  • TheCanadian
  • · Replies 2 ·
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2

High School Is the Universe Infinitely Large Since the Big Bang?

  • kjamha
  • · Replies 1 ·
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1

Undergrad Is Stellarium More Accurate Than VSOP87?

  • Tegalad
  • · Replies 2 ·
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2

Undergrad What Does the h Subscript 70 to the Power of 3 Mean in Supernova Units?

  • resurgance2001
  • · Replies 4 ·
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4

Undergrad How is the first multipole calculated from the Plank Study?

  • Jules Winnfield
  • · Replies 1 ·
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1

High School How are asteroids detected if they absorb sunlight?

  • Albertgauss
  • · Replies 9 ·
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9

Undergrad Why do things fall into a black hole?

  • Singlau
  • · Replies 2 ·
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2

Undergrad Why do planets follow the same curvature at both foci?

  • StandardsGuy
  • · Replies 12 ·
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12

High School Determining the transition frequency

  • TheCanadian
  • · Replies 2 ·
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2

Undergrad Should dark matter and dark energy have completely different models from ordinary matter?

  • Sheldon Cooper
  • · Replies 2 ·
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2

High School What would happen if 6 black holes surrounded a planet?

  • phillovix
  • · Replies 15 ·
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15

High School Could a black hole be hiding inside a neutron star?

  • James Minwell
  • · Replies 3 ·
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3

Undergrad Would quantum laws work in other hypothetical universes?

  • FallenApple
  • · Replies 3 ·
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3

High School Theory that challenges Einstein's physics could soon be put to rest

  • wolram
  • · Replies 9 ·
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9

Graduate Is the Cosmic Microwave Background Linked to Dark Energy?

  • RankAstronamateur
  • · Replies 6 ·
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6

Undergrad How do mass and temperature change in black holes due to Hawking Radiation?

  • James Way
  • · Replies 3 ·
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3

Undergrad Could Bullet Cluster dark matter be primordial black holes instead of particles?

  • kodama
  • · Replies 9 ·
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9

High School Black hole event horizons: shape, singularities, and jets

  • K. Doc Holiday
  • · Replies 2 ·
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2

Graduate Understanding MASERs and their properties

  • TheCanadian
  • · Replies 1 ·
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1

High School Can Orbiting Bodies Slow Down Over Time?

  • micropulsar
  • · Replies 11 ·
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11

High School Why doesn't a black hole appear bright if infalling matter looks frozen at its surface?

  • charles watson
  • · Replies 27 ·
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27

Undergrad Does permeability of free space change with applied magnetic fields?

  • MarSuper
  • · Replies 12 ·
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12

High School Can Hydrogen-Based Plastic Provide Better Radiation Protection than Lead?

  • entrance
  • · Replies 4 ·
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4

High School Temperature in the space between planets of our solar system?

  • Albertgauss
  • · Replies 11 ·
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11

High School Why do spiral galaxy arms bifurcate and what direction is the matter moving?

  • Sanborn Chase
  • · Replies 25 ·
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25

High School Discussing Juno/JunoCam Mission and Jupiter Data

  • 1oldman2
  • · Replies 112 ·
4
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112

High School Can civilizations 4 light years apart detect each other without radio?

  • lifeonmercury
  • · Replies 21 ·
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21

High School Dark matter interacts with visible matter via gravity

  • Sanborn Chase
  • · Replies 5 ·
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5

High School Is a Black Hole Really Just a Spherical Structure?

  • Simon Peach
  • · Replies 52 ·
2
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52

Undergrad Where does a polytropic EoS come from?

  • Vrbic
  • · Replies 2 ·
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2

Graduate Did the universe Absolutely begin?

  • JhonnyDx
  • · Replies 47 ·
2
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47

Undergrad What are black holes made of?

  • Will K
  • · Replies 1 ·
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1

Undergrad Black Hole Time Dilation: What Would an Astronaut See?

  • Will K
  • · Replies 4 ·
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4

High School Infinite amount of matter in the universe?

  • lifeonmercury
  • · Replies 53 ·
2
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53

High School What is the speed of cosmic rays in km/s?

  • Dr Wu
  • · Replies 8 ·
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8

High School Is There a Limit to the Expansion of the Universe?

  • Subrata Paul
  • · Replies 2 ·
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2

Undergrad Does stellar glare affect starlight passing through an exoplanet's atmosphere?

  • akashpandey
  • · Replies 6 ·
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6

High School Living on Titan: A New World for Humans?

  • lifeonmercury
  • · Replies 1 ·
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1

High School Action and reaction of a rocket in space.

  • Clara Chung
  • · Replies 3 ·
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3

High School Is the effect of gravity limited by distance?

  • lifeonmercury
  • · Replies 29 ·
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29

Undergrad Feasibility of terraforming Mars for a technical writing project

  • juanitosguitar
  • · Replies 14 ·
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14

High School How does black hole merger cause loss of mass?

  • danihel
  • · Replies 8 ·
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8

Stargazing How Can Both Jets from a Black Hole Appear to Move Faster Than Light?

  • K. Doc Holiday
  • · Replies 3 ·
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3

High School Are all galaxies moving away from the Milky Way?

  • Pbody101
  • · Replies 16 ·
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16

High School Can a true vacuum exist if gravitons cannot be shielded?

  • Delta2
  • · Replies 32 ·
2
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32

High School Thickness & Distance of Milky Way at Sun's Location

  • lifeonmercury
  • · Replies 3 ·
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3

High School Are black holes white or monochromatic?

  • newjerseyrunner
  • · Replies 3 ·
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3

Graduate Philosophy of a Mathematical Multiverse

  • FallenApple
  • · Replies 1 ·
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1

Undergrad How did scientists figure out the expansion is accelerating?

  • resurgance2001
  • · Replies 1 ·
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1

Undergrad Is the Cosmic Void Between Galaxies Truly Empty?

  • Mohd Abdullah
  • · Replies 6 ·
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6

High School How can we create a map of the universe?

  • Andrew Whalen
  • · Replies 19 ·
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19

High School Height measurement on other planets

  • Gustav S
  • · Replies 1 ·
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1

Graduate Can white dwarf density be reproduced in a lab, and what form of matter are they?

  • K. Doc Holiday
  • · Replies 2 ·
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2

Stargazing Researching AN Ursae Majoris B for Supernova Possibilities

  • K. Doc Holiday
  • · Replies 2 ·
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2

High School Luminosity and neutrino questions

  • K. Doc Holiday
  • · Replies 8 ·
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8

Stargazing Bright stationary light with flashing lights in the night sky

  • jane ellis
  • · Replies 12 ·
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12

High School Can we detect ancient EMR attenuation from before the recombination epoch?

  • stoomart
  • · Replies 10 ·
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10

High School Re-evaluating Dark Matter and Kepler's Law in Spiral Galaxies

  • Trenton
  • · Replies 3 ·
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3

Undergrad How can gravity hold galaxy groups togehter?

  • Tryggvas
  • · Replies 5 ·
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5

High School Retrograde star orbits in the Milky Way

  • lifeonmercury
  • · Replies 15 ·
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15