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 Questions about Negative Pressure and Vacuum Energy

  • darkdark10
  • · Replies 5 ·
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5

Undergrad If the Universe had a different size, would physics change?

  • Suekdccia
  • · Replies 15 ·
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15

Undergrad Is the CPT-Symmetric Universe Theory the Key to Solving the Antimatter Mystery?

  • Quarker
  • · Replies 1 ·
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1

Undergrad Alexander Vilenkin and energy of a closed universe

  • Question69
  • · Replies 32 ·
2
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32

High School Sun contains more oxygen, silicon and neon than previously thought

  • Astronuc
  • · Replies 5 ·
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5

Undergrad Seeking reference for math related to the age of Recombination

  • Buzz Bloom
  • · Replies 3 ·
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3

Undergrad Lateral offset from a centered star as measured at the focal plane

  • Benschu
  • · Replies 3 ·
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3

Undergrad Magnetar Mystery: How Do Neutrons Generate a Magnetic Field?

  • swampwiz
  • · Replies 3 ·
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3

High School Derivation for Aphelion and Perihelion Distances

  • bruhh
  • · Replies 3 ·
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3

Undergrad What is the current status of Voyager 1's attitude and control system?

  • Alltimegreat1
  • · Replies 34 ·
2
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34

Undergrad How to use astronomical spectra?

  • yucheng
  • · Replies 3 ·
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3

Undergrad European Southern Observatory (Event Horizon Project team) – picture of Sgr A*

  • pinball1970
  • · Replies 12 ·
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12

High School What day/exact time does Sun start to move again? (1980 Winter Solstice)

  • UniversalEnergy03
  • · Replies 13 ·
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13

Undergrad What happens first -- Sun Red Giant or Andromeda collision?

  • Philosophaie
  • · Replies 3 ·
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3

Undergrad Dawn dead in Ceres orbit, ran out of fuel Oct 2018

  • marcus
  • · Replies 1K ·
36
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1K

High School Explaining Cosmic Inflation using analogies

  • Paolo 2008
  • · Replies 3 ·
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3

Graduate Understanding distances in Cosmology

  • Arman777
  • · Replies 1 ·
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1

High School Scope Eyepiece diameter for old eyes

  • DaveC426913
  • · Replies 1 ·
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1

Undergrad Will the upcoming experiment PICO measure kSZ temperature anisotropy?

  • SherLOCKed
  • · Replies 1 ·
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1

High School Event Horizon Telescope, Milky Way supermassive black hole stream

  • Orodruin
  • · Replies 8 ·
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8

High School Is Entropy the Key to Understanding the Big Bang and the Fate of the Universe?

  • C_Nordquist
  • · Replies 27 ·
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27

High School Which Way Do Planets in Our Galaxy Spin?

  • Canada Bob
  • · Replies 7 ·
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7

High School Our Sun's position in the Milky Way Galaxy

  • abdossamad2003
  • · Replies 2 ·
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2

High School How does the Milky Way galaxy move in the local Group?

  • abdossamad2003
  • · Replies 2 ·
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2

Undergrad Looking for a chart showing various growths of the Universe

  • Buzz Bloom
  • · Replies 14 ·
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14

High School Accelerating to a stop in the Milky Way Galaxy

  • Dang3rmouse
  • · Replies 8 ·
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8

Graduate Peebles Equation for fractional electron density

  • member 657093
  • · Replies 7 ·
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7

Undergrad What's the source of energy for the universe's expasion?

  • lordoftheselands
  • · Replies 5 ·
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5

High School How good are our ears? (Detectable Interstellar signals)

  • Canada Bob
  • · Replies 7 ·
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7

Stargazing Planetary Lineup and Eclipse Viewing Tips for Cruise Ship Passengers

  • neilparker62
  • · Replies 12 ·
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12

Stargazing Size of Star Images: Electronic Effect, Feynman Paths, or Daft Question?

  • TerryW
  • · Replies 4 ·
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4

Undergrad Do gravitons interact with gravitons?

  • KurtLudwig
  • · Replies 100 ·
4
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100

Graduate Can Representing Ideas be Possible?

  • BiaCarvalho
  • · Replies 8 ·
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8

High School Would like to explore the Henry Draper catalogue of stars

  • Cerenkov
  • · Replies 2 ·
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2

Undergrad A busy and interesting night sky in Mackinaw City

  • Kwantumnaut
  • · Replies 1 ·
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1

Undergrad Observations fit poorly with the Standard Model of Cosmology

  • Buzz Bloom
  • · Replies 34 ·
2
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34

High School Mini spacecraft to Alpha Centauri

  • kolleamm
  • · Replies 11 ·
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11

Undergrad How is the sound horizon at recombination and BAO measured in the CMB?

  • jordy1113
  • · Replies 1 ·
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1

Undergrad How far into the Universe can we theoretically reach?

  • plin092
  • · Replies 34 ·
2
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34

Undergrad Is Entropy in the Universe Lower Now Than After the Big Bang Due to Heat?

  • shlosmem
  • · Replies 25 ·
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25

Undergrad What Prevents Electrons from Expanding Radially in White Dwarfs?

  • MarkL
  • · Replies 7 ·
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7

Undergrad Varying laws of high energy physics in inflation?

  • Suekdccia
  • · Replies 4 ·
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4

High School First Interstellar Asteroid Found

  • CygnusX-1
  • · Replies 125 ·
5
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125

Undergrad First Interstellar Object to Hit Earth

  • Jarvis323
  • · Replies 2 ·
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2

Undergrad Gravitational Field with Dark Energy: Observable Effects?

  • kodama
  • · Replies 1 ·
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1

Stargazing Hubble Spots Farthest Star Ever Seen

  • diogenesNY
  • · Replies 9 ·
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9

Undergrad An odd result from integrating to calculate the age of the Universe

  • Buzz Bloom
  • · Replies 21 ·
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21

Undergrad Information lost at the Big Crunch?

  • Suekdccia
  • · Replies 3 ·
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3

Undergrad What Does Radiation Do to Space Ice?

  • Albertgauss
  • · Replies 12 ·
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12

Undergrad Questions about bayronic acoustic oscillations

  • Buzz Bloom
  • · Replies 9 ·
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9

Undergrad The Big Bang and the original size of Universe

  • Martyn Arthur
  • · Replies 1 ·
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1

High School Can electromagnetic waves traverse wormholes?

  • GatherEvidence
  • · Replies 8 ·
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8

High School Is Language Barrier a Reason for Our Limited Understanding of Black Holes?

  • A. Neumaier
  • · Replies 23 ·
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23

Undergrad MOND from galaxies that are fractal

  • kodama
  • · Replies 10 ·
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10

Graduate Questions: Gott-Li Can a Universe Create Itself?

  • AntHak
  • · Replies 2 ·
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2

High School What is the oldest of each class of star?

  • plin092
  • · Replies 2 ·
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2

High School Northern Lights Visible in Mid States Tonight

  • DaveC426913
  • · Replies 4 ·
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4

High School Why combine the JWST data physically instead of digitally?

  • DaveC426913
  • · Replies 6 ·
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6

High School Could anything heat back up the core of Mars?

  • Isopod
  • · Replies 9 ·
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9

Stargazing Is There a Reliable Supernova Alert System?

  • Loup909
  • · Replies 5 ·
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5

High School What happens to the Core of a main sequence star as additional mass is added?

  • MikeeMiracle
  • · Replies 42 ·
2
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42

Undergrad Is a horseshoe orbit a hyperbolic orbit?

  • Mike S.
  • · Replies 2 ·
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2

Undergrad Information loss in black hole, why is it a problem?

  • OscarCP
  • · Replies 10 ·
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10

High School Experimental evidence on cosmological redshift

  • zrek
  • · Replies 34 ·
2
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34

Undergrad Does Dark Matter Fall into Black Holes?

  • Godot_
  • · Replies 12 ·
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12

Undergrad Surface Differential Rotation by measuring the position of sunspots

  • TheSpectacularSpecs
  • · Replies 1 ·
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1

Graduate Which galaxies have the best studied evidence for dark matter?

  • timjdoom
  • · Replies 4 ·
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4

Undergrad Where does the Sol system lie in the cross-section of the Orion Spur?

  • AotrsCommander
  • · Replies 2 ·
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2

Stargazing Spotting Meteorites: Unveiling the Mystery of Annual Showers

  • sophiecentaur
  • · Replies 50 ·
2
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50

Undergrad How Does Gravity Affect Spectral Line Strength?

  • Angela G
  • · Replies 2 ·
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2

Undergrad Back of the envelope estimate, energy flow in a box of plasma

  • Spinnor
  • · Replies 1 ·
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1

Graduate Graceful exit of a cosmological inflation model

  • Alpha2021
  • · Replies 3 ·
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3

Undergrad What causes the precession of the equinox?

  • Trying2Learn
  • · Replies 7 ·
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7

High School Is the Earth falling into the sun from gravity?

  • BadgerBadger92
  • · Replies 7 ·
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7

Undergrad Universe Expansion: Does Less Dense Mean Boundaries?

  • MagneticMagic
  • · Replies 4 ·
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4

Undergrad What does the equation dΩ32 = dr2 + r2dΩ22 mean in terms of flat space?

  • knowwhatyoudontknow
  • · Replies 6 ·
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6

Undergrad Impact on Earth: Calculating Energy

  • mukuruku
  • · Replies 2 ·
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2

High School The configuration of galaxies in space

  • PainterGuy
  • · Replies 4 ·
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4

High School What Function Does Dark Matter or Energy Serve?

  • Zeal Faust
  • · Replies 13 ·
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13

High School Different stars visible from northern and southern hemispheres

  • PainterGuy
  • · Replies 9 ·
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9

High School For object 3.26 million light-years away, light redshifted by 70 km/s

  • PainterGuy
  • · Replies 12 ·
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12

Undergrad Are Two Supermassive Black Holes on a Collision Course?

  • Tom.G
  • · Replies 2 ·
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2

Graduate Numerically solving Scalar field coupled to Friedman equation

  • Soony143
  • · Replies 3 ·
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3

Stargazing Upcoming Supernova? | Nature News

  • Oldman too
  • · Replies 4 ·
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4

High School How could something that is infinite (the Universe) expand?

  • alae
  • · Replies 30 ·
2
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30

High School Revealing Secrets of Distant Supernova DES16C2nm: 10.5 Billion Years Ago

  • Ziang
  • · Replies 69 ·
3
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69

High School Light and the black matter (Dark Matter)

  • angela
  • · Replies 2 ·
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2

High School Asteroid/Near Earth object mining

  • 1oldman2
  • · Replies 146 ·
5
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146

High School Questions about Lagrange points in the Pluto / Charon system

  • Cerenkov
  • · Replies 2 ·
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2

High School What does the Universe exapand into?

  • HG009
  • · Replies 27 ·
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27

High School Alcyoneus Radio Galaxy: Myth or Reality? Discover the Truth Here!

  • MikeC111
  • · Replies 2 ·
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2

Undergrad Energy conservation in Doppler (NOT cosmological) redshifts?

  • Amaterasu21
  • · Replies 13 ·
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13

Undergrad Calculating the probability that the Universe is finite

  • Buzz Bloom
  • · Replies 70 ·
3
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70

Undergrad Why does Webb orbit L2, is it because of the Moon?

  • bland
  • · Replies 58 ·
2
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58

Undergrad How to Experimentally Measure the MTF of a Lens?

  • Gifty01
  • · Replies 1 ·
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1

High School NGC 4590, more than 1,400 stars found in various evolutionary stages

  • Astronuc
  • · Replies 1 ·
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1

Undergrad Radioactive Dating of Asteroid Elements: How Do Scientists Know?

  • Albertgauss
  • · Replies 2 ·
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2

Undergrad What Are the Theories Behind the Moon's Formation?

  • HG009
  • · Replies 15 ·
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15

Undergrad What if the Universe expands faster than the speed of light?

  • peterraymond
  • · Replies 19 ·
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19

High School I wonder why massive objects slow down time

  • HG009
  • · Replies 7 ·
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7