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 Conjuction of planets to Earth, it affects our weight?

  • Numeriprimi
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Graduate Estimates of galaxy numbers - re Herschel resuts

  • Paulibus
  • · Replies 7 ·
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7

Graduate Are Hawking's Equations for Black Hole Energy and Evaporation Time Flawed?

  • liometopum
  • · Replies 10 ·
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10

Graduate What is the current status on MOND

  • Tanelorn
  • · Replies 19 ·
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19

Graduate Hi there. Just looking at an astophysics journal article in which they

  • SUDOnym
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Graduate Where does the energy vanish to when light is red shifted

  • SteveinLondon
  • · Replies 44 ·
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44

Undergrad A rudementary question on dark matter

  • hms.tech
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Graduate When does a massive star become a neutron star vs. a black hole?

  • shounakbhatta
  • · Replies 9 ·
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9

Graduate The observable universe, the actual uinverse, and CMB

  • curioushuman
  • · Replies 38 ·
2
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38

Graduate What causes the red-shift observed in distant galaxies?

  • binbagsss
  • · Replies 7 ·
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7

High School In essence how does time travel relate to space?

  • neugie92
  • · Replies 7 ·
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7

Graduate How do the tidal forces warming moons theories hold when []

  • cdux
  • · Replies 12 ·
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12

Graduate Are Cosmic Strings Connected to Other Dimensions and Gravitons?

  • SpaceDreamer
  • · Replies 3 ·
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3

Undergrad Light Years: Subjectivity and Distance Measurement

  • neugie92
  • · Replies 5 ·
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5

Graduate Will all stars eventually become black holes and collapse into a singularity?

  • zepp0814
  • · Replies 6 ·
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6

Undergrad Big Bang theory vs. the universe as we know it

  • Low-Q
  • · Replies 8 ·
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8

Graduate I cant imagine the expanding universe in my head

  • jaydnul
  • · Replies 12 ·
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12

Graduate Is the event horizon of a black hole physical?

  • phinds
  • · Replies 70 ·
3
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High School Can the Sagittarius and Canis Major Dwarf Galaxies be Seen with the Naked Eye?

  • shounakbhatta
  • · Replies 19 ·
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19

Graduate Could a Variable Speed of Light Theory Challenge the FLRW Metric in Cosmology?

  • anorlunda
  • · Replies 2 ·
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2

Graduate Are Black Holes the Ultimate Cleaners of the Universe?

  • uperkurk
  • · Replies 3 ·
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3

Undergrad Could an ion engine attached to a satellite be used to stabilize orbit?

  • vjk2
  • · Replies 5 ·
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5

High School Realistic space flight simulator iOS

  • devGirl
  • · Replies 1 ·
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1

Graduate Primordial black holes as DM candidates

  • Chronos
  • · Replies 2 ·
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2

High School Do stars rotate, and if so how is angular momentum involved?

  • shounakbhatta
  • · Replies 4 ·
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4

Graduate Would Distant Galaxies Still Exist If Time Were Paused?

  • jaydnul
  • · Replies 9 ·
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9

Graduate Can dark matter form planets and dark matter life?

  • silvercats
  • · Replies 13 ·
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13

Graduate Back and forward orbit [around gravitating objects]

  • Edi
  • · Replies 52 ·
2
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Undergrad Space Elevators -> US Transportation Infrastructure

  • blu3boy
  • · Replies 23 ·
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23

Graduate Universe expansion faster than light?

  • mrxyz
  • · Replies 3 ·
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3

Undergrad What would a toroidal planet be like?

  • EskWIRED
  • · Replies 16 ·
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16

Undergrad Why there is so little carbon in Earth crust?

  • Czcibor
  • · Replies 2 ·
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2
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7

Graduate Does the big bang explain physical or philosophical nothing?

  • Jason12381
  • · Replies 9 ·
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9

Undergrad What Causes Elliptical Galaxies to be Elliptical?

  • shounakbhatta
  • · Replies 4 ·
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4

Graduate Planetary Formation Based on Matter Condensation and Accretion

  • PhysicsPost
  • · Replies 2 ·
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2

Undergrad Is the Universe Expanding or Has it Already Expanded?

  • C. Bernard
  • · Replies 96 ·
4
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Graduate Can torsion avoid the big bang singularity

  • Naty1
  • · Replies 7 ·
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7

Undergrad Universe expansion beyond c at some distant point?

  • k!rl
  • · Replies 9 ·
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9

Undergrad Do orbital shapes change from ellipse to parabola to hyperbola with stronger gravity?

  • shounakbhatta
  • · Replies 2 ·
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2

Undergrad Can you reach absolute zero in complete empty space

  • mcafej
  • · Replies 14 ·
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14

Undergrad Does redshift reduce the observed temperature of distant stars?

  • samsara15
  • · Replies 3 ·
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3

Undergrad Importance of a standard candle?

  • NanaToru
  • · Replies 3 ·
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3

Undergrad Measuring the distance to stars using parallax

  • alemsalem
  • · Replies 3 ·
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3

Undergrad Interpreting negative declination values in asteroid coordinates

  • BOYLANATOR
  • · Replies 2 ·
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2

Undergrad Maintaining orbit around the moon

  • vjk2
  • · Replies 8 ·
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8

Graduate Perpetual acceleration of the universe expansion?

  • JuanCasado
  • · Replies 6 ·
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6

Graduate Million Kelvin gas clouds? Really?

  • Antiphon
  • · Replies 16 ·
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16

Graduate Can gravity balance the other forces without mass in zero-energy models?

  • Mordred
  • · Replies 10 ·
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10

Graduate Formula for the star density of the milky way?

  • pere plank
  • · Replies 1 ·
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1

Graduate Mechanism for generating the energy in supernova

  • mrcotton
  • · Replies 10 ·
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10

High School Has Andromeda Moved Closer in 2.5 Million Years?

  • jonorion
  • · Replies 17 ·
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Graduate Why would gravity slow down the Universe's expansion?

  • rfoshaug
  • · Replies 4 ·
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4

Undergrad What would Earth's gravitational acceleration from the Sun be without Earth?

  • cdux
  • · Replies 6 ·
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6

On which altitude does the heaven turns in black?

  • nickek
  • · Replies 5 ·
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5

Undergrad How does parallax of a distant reference object help measure a nearby object?

  • NanaToru
  • · Replies 3 ·
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3

Undergrad Milkyway Black-hole vs Andromeda Collision

  • omar1
  • · Replies 1 ·
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1

Graduate Quasar Turn On z<1 Quasar Clustering

  • betzalel
  • · Replies 2 ·
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2

Graduate Most logical answer for the universe

  • WanderingShugo
  • · Replies 1 ·
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1

Graduate Flat Universe, dark energy and accelerating expansion

  • say_cheese
  • · Replies 11 ·
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11

Graduate Why does redshift prove cosmic expansion and not just spacetime expansion?

  • Egregious
  • · Replies 5 ·
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5

Graduate Can the Multiverse Expand Without a Realm to Expand Into?

  • cdux
  • · Replies 22 ·
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22

High School Astrophysics Prerequisites Question

  • Cjjw
  • · Replies 2 ·
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2

Graduate Largest Structure in Universe: 4B Light-Years Long LQG

  • Astronuc
  • · Replies 2 ·
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2

Graduate Olbers paradox applied to gravity with infinite planets

  • cragar
  • · Replies 3 ·
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3

Graduate Large quasar group spanning 4 billion light-years challenges cosmological principle

  • Tanelorn
  • · Replies 1 ·
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1

Undergrad Did Astronauts Face Dangerous Radiation During Apollo Missions?

  • inthesky
  • · Replies 2 ·
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2

Graduate What you always wanted to know about dark matter?

  • wolram
  • · Replies 2 ·
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2

Stargazing Celestron UpClose Porro Series 10-30 x 50 Zoom Binoculars

  • BH Wiz
  • · Replies 4 ·
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4

Undergrad KOI 172.02: 1.5 Earth masses in a 242-day orbit

  • Astronuc
  • · Replies 1 ·
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1

Graduate Is the Local Fluff Causing Warming in Our Solar System?

  • brooklyn2008
  • · Replies 3 ·
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3

Undergrad What is the Solar Constant in the Kuiper Belt?

  • ninab
  • · Replies 1 ·
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1

Graduate Accelerating Universal Expansion

  • Maxila
  • · Replies 6 ·
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6

Undergrad The lost energy of Cosmic Background Radiation

  • JuanCasado
  • · Replies 23 ·
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23

Graduate Velocity Dispersion Questions - Shounak

  • shounakbhatta
  • · Replies 11 ·
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11

Graduate Can we see the Big Bang if particles from it reach us at different speeds?

  • Erland
  • · Replies 11 ·
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11

Graduate Does an Infinite Universe Challenge the Laws of Thermodynamics?

  • Crazymechanic
  • · Replies 12 ·
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12

Undergrad Why don't astronomers consider precession as a main movement of Earth?

  • Franco Malgari
  • · Replies 13 ·
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13

Graduate Why is the universe's existence significant?

  • NWH
  • · Replies 1 ·
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1

Graduate Planar structure of dwarf galaxies orbiting Andromeda

  • TrickyDicky
  • · Replies 3 ·
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3

Graduate Can pre-big-bang information survive the crunch?

  • anorlunda
  • · Replies 12 ·
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12

High School What is the difference between Sagittarius A and Sagittarius A*?

  • shounakbhatta
  • · Replies 14 ·
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14

Graduate Projected Separation and 3D Distance Problem (Code Included)

  • FiberOptix
  • · Replies 4 ·
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4

Graduate Similarities of negative absolute temperature to dark energy?

  • julcab12
  • · Replies 6 ·
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6

Graduate Role of Strong Force in Neutron Stars

  • Drakkith
  • · Replies 7 ·
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7

Graduate What's the Deal with Astrophysical Jets?

  • SHISHKABOB
  • · Replies 5 ·
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5

Graduate Relativistic at freeze out? Definition of HDM

  • cohen990
  • · Replies 2 ·
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2

Undergrad Exoplanet Maps: Northern and Southern Hemisphere Locations

  • Bobbywhy
  • · Replies 2 ·
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2

High School Does the Milky Way orbit something at its center?

  • sprasannaonlin
  • · Replies 3 ·
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3

Graduate Does dark matter act as a medium for sound to go through?

  • Sk8ernicky
  • · Replies 10 ·
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10

Undergrad How does Angular Momentum relate to the rapid rotation of Pulsars?

  • AbsoluteZer0
  • · Replies 2 ·
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2

Undergrad Stars heat up when they lose energy

  • SUDOnym
  • · Replies 1 ·
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1

Undergrad The equilibrium in the universe ?

  • dido28
  • · Replies 8 ·
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8

Graduate Can negative absolute temperatures occur in the cosmos?

  • shifty88
  • · Replies 1 ·
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1

Undergrad How Does Gravitational Lensing Bend Light in Space?

  • shadytriba
  • · Replies 3 ·
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3

Undergrad Does a black hole have size if it's collapsed to a singularity?

  • goldsax
  • · Replies 5 ·
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5

Graduate Alpher Bethe Gamow: Factor characterizing the decrease of density with time

  • pianoplayer98
  • · Replies 1 ·
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1

High School The Universe. Orderly, Chaotic, or some of both?

  • OrionVTOL
  • · Replies 29 ·
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29

Undergrad Is it possible at all to go faster in an orbit around the earth?

  • vjk2
  • · Replies 5 ·
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5

Undergrad Calculating the moon's mass from Earth distance and diameter

  • wasi-uz-zaman
  • · Replies 4 ·
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4