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 Dark Matter Disc Evidence: New Possibilities in Milky Way Galaxy

  • Buzz Bloom
  • · Replies 4 ·
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4

High School The Factors affecting the Orbitals of a moon

  • Copernicus45
  • · Replies 2 ·
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2

Undergrad Actual number of stars in the Milky Way

  • Stickman76
  • · Replies 5 ·
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5

Stargazing What's the Best Telescope for Astrophotography Under $1,500?

  • kolleamm
  • · Replies 25 ·
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25

Graduate Are period 5 elements common in most stars?

  • Guilherme Franco
  • · Replies 4 ·
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4

Undergrad Methods of Hawking radiation generation

  • Leyzorek
  • · Replies 2 ·
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2

Undergrad Galaxy Rotation Curves and Mass Discrepancy

  • redtree
  • · Replies 1 ·
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1

Stargazing Focussing a Pentax K S2 with Live View for Moon Photography

  • sophiecentaur
  • · Replies 10 ·
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10

Undergrad Where Does the Cosmic Microwave Background Come From and How is it Measured?

  • Silviu
  • · Replies 21 ·
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21

Undergrad Tight grouping of exoplanets 295RA 45dec

  • nearc
  • · Replies 14 ·
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14

Stargazing Recommendations for a beginner telescope under $100

  • chrismcgivney
  • · Replies 13 ·
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13

Stargazing What was the reaction to the Hubble telescope's pictures?

  • revv
  • · Replies 23 ·
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23

Undergrad Is the Sun considered a dwarf star?

  • Roach DN
  • · Replies 19 ·
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19

High School Has anyone photographed the spectrum of ball lightning?

  • efdee
  • · Replies 12 ·
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12

Undergrad Is there a table of electric dipole moments for celestial bodies?

  • Philosophaie
  • · Replies 16 ·
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16

Undergrad Dark Energy Not Constant: New Claims

  • windy miller
  • · Replies 3 ·
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3

High School Can inertia be quantised? McCulloch's solution to galaxy rotation without dark matter?

  • wolram
  • · Replies 37 ·
2
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37

High School Time Lapse of Supernova SN1987A - 30 Years in Under a Minute

  • BillTre
  • · Replies 5 ·
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5

High School High School video project: What is Gravitational Lensing?

  • Xander Jake
  • · Replies 1 ·
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1

High School What do astronomers think caused the Wow! signal?

  • lifeonmercury
  • · Replies 23 ·
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23

Undergrad How to deal with the celestial meridian?

  • Heatherfield
  • · Replies 1 ·
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1

Undergrad Dark Matter Size to be seen in our solar system

  • Albertgauss
  • · Replies 5 ·
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5

High School What defines planetary core, mantle and crust?

  • swampwiz
  • · Replies 5 ·
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5

Undergrad Finding parameters for equation 1 in JGRA.50543 for 100-300 km satellite height

  • Sokos90
  • · Replies 4 ·
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4

High School We have kittens in orbit around Saturn

  • Noisy Rhysling
  • · Replies 3 ·
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3

High School Where Can I Find the RA and Dec of the V1 Star?

  • Curious Kid
  • · Replies 6 ·
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6

High School Black holes in the centres of galaxies

  • davidge
  • · Replies 27 ·
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27

Cassini's Grand Finale - Fascinating New Insight

  • Stavros Kiri
  • · Replies 49 ·
2
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49

Stargazing How Does Gravitational Lensing Work?

  • Soundariya Raja
  • · Replies 13 ·
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13

High School What are the mystery lights in the sky and how can you identify them?

  • jedishrfu
  • · Replies 4 ·
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4

High School Does the Singularity Really Exist Beyond the Standard Model?

  • wolram
  • · Replies 6 ·
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6

High School A terrestrial, temperate planet around Proxima Centauri

  • Ygggdrasil
  • · Replies 60 ·
3
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60

Undergrad What spatial scales does dark matter become significant?

  • Albertgauss
  • · Replies 3 ·
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3

High School Is there a way to prove that men have gone to the moon

  • Tio Barnabe
  • · Replies 23 ·
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23

High School Understanding Black Body Radiation and the Sun's Color Temperature

  • riz
  • · Replies 2 ·
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2

Stargazing Stunning 2017 Eclipse Photos of the Corona Chromosphere

  • Chronos
  • · Replies 68 ·
3
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68

High School The Most Primitive Star-Forming Galaxy Ever Found

  • CygnusX-1
  • · Replies 2 ·
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2

Undergrad Expanding universe and quantum wavefunctions

  • durant35
  • · Replies 11 ·
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11

Stargazing Child-like pleasure in seeing ISS and detached Dragon capsule

  • UsableThought
  • · Replies 7 ·
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7

High School Could we shade the Earth from the Sun to save Earth?

  • Bmaxwell
  • · Replies 26 ·
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26

Undergrad Did Phase Transitions Drive Inflation in the Early Universe?

  • Vrbic
  • · Replies 9 ·
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9

Undergrad T-symmetry and WDWE with regards to a Universe from Nothing

  • zeroace
  • · Replies 7 ·
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7

High School How does the earth's magnetic field stop radiation?

  • Lunct
  • · Replies 24 ·
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24

Undergrad What is the best source for COBE/WMAP/PLANCK mission data on the early universe?

  • RJLiberator
  • · Replies 2 ·
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2

High School Planetary rings, moons, and asteroid belts for a habitable world

  • Shawn Landau
  • · Replies 7 ·
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7

Graduate Galaxy rotation curves without dark matter using baryonic matter

  • Adrian59
  • · Replies 1 ·
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1

High School Can Optical Interferometers Extend Beyond 1 Light Second in Length?

  • smartalek86
  • · Replies 1 ·
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1

Graduate Press Schechter function -- the variance on mass scale

  • classy cal
  • · Replies 1 ·
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1

High School How often do stars collide in galaxies?

  • davidge
  • · Replies 14 ·
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14

High School What do you think of the new names for features on Pluto

  • wolram
  • · Replies 2 ·
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2

Stargazing Worth it to buy 2" eyepieces for Newtonian telescope?

  • lomidrevo
  • · Replies 27 ·
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27

High School Can an 18-inch telescope resolve an Earth-like exoplanet?

  • kolleamm
  • · Replies 6 ·
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6

Stargazing Space debris threat to Hubble and other satellites

  • UsableThought
  • · Replies 1 ·
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1

Undergrad Questions about planetary magnetic fields

  • Hawksteinman
  • · Replies 11 ·
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11

Undergrad Event Horizon and the Mass of a Black Hole

  • Arman777
  • · Replies 12 ·
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12

Undergrad What causes pressure in White Dwarfs and Neutron Stars?

  • Ethan Singer
  • · Replies 4 ·
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4

Graduate Is the Parenago Discontinuity a real thing?

  • DrBwts
  • · Replies 7 ·
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7

Undergrad Safe distance from a neutron star

  • Blue Shift 2112
  • · Replies 4 ·
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4

Undergrad Meaning of permeability in free space

  • TheCanadian
  • · Replies 10 ·
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10

Undergrad Dark matter/energy, why must it be there?

  • Pedro Batista
  • · Replies 30 ·
2
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30

Undergrad Is the speed of gravitational waves non- dispersive?

  • shadishacker
  • · Replies 1 ·
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1

Undergrad Why are the planets revolving around their own axis?

  • Neolight
  • · Replies 21 ·
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21

High School Does gravity self interact with itself

  • wolram
  • · Replies 7 ·
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7

Undergrad What would rainbows look like in a binary star system?

  • stefan r
  • · Replies 1 ·
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1

High School Does this paper disprove the possibility of a new universe creation?

  • Yid
  • · Replies 3 ·
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3

Stargazing Aurora Alert for 6th and 7th Sept

  • davenn
  • · Replies 6 ·
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6

High School Does expanding spacetime affect how gravity propagates?

  • Chris Miller
  • · Replies 87 ·
3
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87

High School Did expansion start from a finite seed or happen everywhere at once?

  • Grinkle
  • · Replies 9 ·
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9

Undergrad Virial Theorem and the Ergodic hypothesis

  • JMatt7
  • · Replies 2 ·
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2

High School How can the Big Bang model apply to the entire universe?

  • icantevenn
  • · Replies 21 ·
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21

Undergrad Comparison of tidal forces acting on the Moon vs Enceladus

  • Vrbic
  • · Replies 56 ·
2
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56

High School Uranus's Moon Cressida is Doomed

  • CygnusX-1
  • · Replies 5 ·
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5

Stargazing Sunspots visible for 2 Sept 2017

  • davenn
  • · Replies 13 ·
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13

High School Why does the Moon sometimes seem red?

  • Eleni_
  • · Replies 9 ·
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9

High School What Theories Explain the Nature and Changes of Space?

  • sanpokhrel
  • · Replies 1 ·
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1

High School See Asteroid Florence Tonight in Frankfurt Germany

  • lifeonmercury
  • · Replies 2 ·
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2

Undergrad What is the actual distance when integrating a(t)*dr in an expanding universe?

  • Apashanka Das
  • · Replies 2 ·
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2

Undergrad Ammonia in icy moons of gas giants

  • smartalek86
  • · Replies 2 ·
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2

High School Big Bang theory and the known universe

  • icantevenn
  • · Replies 29 ·
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29

Undergrad Models of accretion disc emissions contradicted by experiment

  • Buzz Bloom
  • · Replies 5 ·
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5

High School What is the age of the universe relative to?

  • Salvador Sosa
  • · Replies 8 ·
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8

High School A Hypothesis To Observe The Formation Of Earth

  • asesena
  • · Replies 12 ·
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12

High School Did the big bang create something from nothing?

  • Lunct
  • · Replies 26 ·
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26

High School Is Our Observable Universe the Actual Size of Our Universe?

  • Lunct
  • · Replies 18 ·
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18

High School Most detailed picture of Antares

  • mfb
  • · Replies 8 ·
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8

High School What factors determine the timing of a solar eclipse?

  • arabianights
  • · Replies 3 ·
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3

High School Asteroid Florence will soon pass Earth

  • tony873004
  • · Replies 1 ·
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1

Stargazing The Sun today - 9 July 2017 - nice spot group

  • davenn
  • · Replies 37 ·
2
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37

High School Why Didn't the Earth Go Dark During Today's Solar Eclipse?

  • rasp
  • · Replies 21 ·
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21

Stargazing 'losing light' 1.25" DSLR coupling vs 2"?

  • mishima
  • · Replies 5 ·
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5

Graduate Definition of [itex]\sigma_8[/itex]

  • Einj
  • · Replies 5 ·
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5

Undergrad Why not detect dark matter in our own galaxy?

  • alejandromeira
  • · Replies 12 ·
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12

Stargazing 2 significant spot groups currently visible

  • davenn
  • · Replies 10 ·
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10

High School Are Gravitational Waves accepted?

  • nmsurobert
  • · Replies 3 ·
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3

High School Is it possible to see sunspots with the unaided eye?

  • BenAS
  • · Replies 15 ·
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15

High School If spacetime can be bent can it be broken?

  • Wallsy
  • · Replies 14 ·
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14

Undergrad How much of inner galaxy rotation curves is due to mass enclosed?

  • redtree
  • · Replies 19 ·
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19

Undergrad Observable Universe Size in Different Perspectives

  • Arman777
  • · Replies 42 ·
2
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42

Stargazing Cloud of ~1000 twinkling stars moving near Jupiter on Feb 20

  • tonyxon22
  • · Replies 32 ·
2
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32

Stargazing Solar Con? Eclipse road trip to Makanda Illinois

  • Blank_Stare
  • · Replies 40 ·
2
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40