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 Any Galaxy (Milky-way) based coordinate systems?

  • vsrawat
  • · Replies 8 ·
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8

High School Expected Earth-relative velocity of interstellar particles

  • Grinkle
  • · Replies 7 ·
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7

High School Interstellar navigation to Proxima B with an unmanned probe

  • BWV
  • · Replies 28 ·
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28

Undergrad Galaxy collision separates dark matter from regular matter

  • DaveC426913
  • · Replies 2 ·
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2

Stargazing Any Heliocentric planetrorium software or site?

  • vsrawat
  • · Replies 2 ·
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2

Stargazing Some photos of Antares and Sigma Sagittarii (Nunki)

  • PhysicsEnjoyer31415
  • · Replies 3 ·
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3

Undergrad Shell structure topological defects as substitute for dark matter

  • Ranku
  • · Replies 3 ·
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3

Graduate HST measures Draco dwarf galaxy over 18 years in DM study

  • pinball1970
  • · Replies 1 ·
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1

Undergrad Stable solutions to simplified 2- and 3-body problems?

  • Exy
  • · Replies 6 ·
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6

Graduate Trying to plot a graph of energy densities for radiation and PBHs

  • di_a_tonic17
  • · Replies 2 ·
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2

Undergrad Very bright geo satellite in my night sky?

  • avicenna
  • · Replies 36 ·
2
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36

Undergrad Diameter of the observable Universe

  • Thecla
  • · Replies 13 ·
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13

Undergrad What is the Possibility of Habitable Planets Around Brown Dwarfs?

  • DiamondTiara
  • · Replies 6 ·
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6

Undergrad Is Baryogenesis a Convincing Hypothesis?

  • Morgo
  • · Replies 3 ·
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3

Undergrad Could cosmic rays induce a vacuum decay in the future?

  • Suekdccia
  • · Replies 5 ·
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5

Undergrad Early Universe massive Black Holes question

  • ShadowKraz
  • · Replies 10 ·
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10

High School Questions about dark matter/energy

  • imsmooth
  • · Replies 50 ·
2
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50

Undergrad Galaxies as systems extended from the solar system

  • Martyn Arthur
  • · Replies 4 ·
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4

Graduate Is the Jeffry Scale/Bayes Factor Still Used for Testing Inflationary Models?

  • Mordred
  • · Replies 0 ·
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0

High School Approximately how long does it take for a galaxy to form?

  • Tanelorn
  • · Replies 12 ·
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12

High School Why is the CNO Cycle considered catalytic in stellar nucleosynthesis?

  • DrLich
  • · Replies 2 ·
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2

High School Is the Universe older than we think?

  • TheOrionNebula
  • · Replies 40 ·
2
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40

High School Discussion on the source or cause of Dark Energy Dark Matter et al

  • Tanelorn
  • · Replies 6 ·
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6

Undergrad Does Organic Matter Experience Gravity on the Moon?

  • samcan
  • · Replies 15 ·
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15

High School Is the Sun's Magnetic Field About to Flip?

  • DaveC426913
  • · Replies 1 ·
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1

High School Question about the Silicon-burning Process beyond iron

  • DrLich
  • · Replies 4 ·
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4

Stargazing How Can You Capture Stunning Moon Photos with a Remote Control?

  • PhysicsEnjoyer31415
  • · Replies 9 ·
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9

High School A question regarding Heliocentric Latitude

  • Mikael17
  • · Replies 1 ·
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1

Graduate Very last pulse from a neutron star

  • CGHW01
  • · Replies 2 ·
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2

Graduate Should luminosity distance be 0 at z=0?

  • johnio09
  • · Replies 4 ·
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4

Graduate Horndeski: denominator null implies an infinite quantity

  • fab13
  • · Replies 16 ·
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16

High School Dark Energy: Are We All Missing The Obvious?

  • despoi1er
  • · Replies 4 ·
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4

Undergrad Unknown Radio Signal from Space Repeats Every Hour -- Usually

  • Tom.G
  • · Replies 6 ·
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6

Undergrad Is the Universe Truly Infinite?

  • outremer
  • · Replies 13 ·
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13

Undergrad Hydrogen line observation frequency range and space Hydrogen speed?

  • Jaaanosik
  • · Replies 33 ·
2
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33

High School Asteroid 2024 BX1 entered Earth's atmosphere over Germany 21 Jan 2024

  • Astronuc
  • · Replies 1 ·
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1

Stargazing What can I see with 10x50 binoculars in Bortle class 4?

  • AryaanHegde
  • · Replies 4 ·
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4

Undergrad What temperature would 1 keV neutrinos have today?

  • ergospherical
  • · Replies 14 ·
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14

Undergrad "Energy is not conserved" vs. energy is conserved: Friedmann Equations

  • timmdeeg
  • · Replies 17 ·
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17

Undergrad Retro/prograde flyby galaxies and their bar formation

  • milkism
  • · Replies 1 ·
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1

High School Are some objects in the night sky just older images of other objects?

  • hjgfx697
  • · Replies 12 ·
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12

Undergrad Questions about paper "How closed is cosmology"

  • KleinMoretti
  • · Replies 18 ·
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18

High School Question about Neon-burning Process

  • DrLich
  • · Replies 2 ·
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2

Undergrad How Does Vera Rubin's Research Support the Existence of Dark Matter in Galaxies?

  • tedj121
  • · Replies 8 ·
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8

Undergrad Observational Astronomy Project Ideas to Show Special Relativity

  • Sciencemaster
  • · Replies 26 ·
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26

Undergrad Brian Cox and the end of the Universe?

  • KDP
  • · Replies 13 ·
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13

Stargazing My photo of Jupiter (I think)

  • PhysicsEnjoyer31415
  • · Replies 4 ·
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4

Undergrad Latest Findings from DESI Collaboration

  • MrRobotoToo
  • · Replies 2 ·
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2

Undergrad I'm slightly confused about the power spectrum of matter

  • ergospherical
  • · Replies 1 ·
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1

High School Question About Dark Energy

  • zuz
  • · Replies 4 ·
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4

Undergrad Speed of light on cosmological scales

  • Grinkle
  • · Replies 9 ·
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9

Undergrad Cosmological Scalar Field Density Dilution

  • Samama Fahim
  • · Replies 3 ·
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3

Graduate Matter density crude estimates

  • Floyd_13
  • · Replies 2 ·
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2

Stargazing Dark matter and its effect on the orbit of stars

  • petercl14
  • · Replies 13 ·
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13

High School Percentage of known energy in the Universe

  • mister i
  • · Replies 9 ·
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9

Stargazing Documenting the setup of my new telescope

  • collinsmark
  • · Replies 54 ·
2
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54

Undergrad Deriving the Roche limit(d) for body of mass M and satellite m

  • PhysicsEnjoyer31415
  • · Replies 4 ·
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4

Undergrad Questions about Black Holes, Hawking Radiation, and Dark Matter

  • ShadowKraz
  • · Replies 11 ·
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11

High School Pressure on creation of the Universe

  • joshcitylife
  • · Replies 7 ·
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7

High School Can the "creation" of space in the Universe affect the speed of light?

  • mister i
  • · Replies 7 ·
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7

Undergrad Can time on elliptical orbit be expressed analytically?

  • snorkack
  • · Replies 6 ·
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6

Undergrad Global properties of the universe

  • south
  • · Replies 10 ·
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10

Undergrad Can there be structures made from neutrinos with angular momentum?

  • Suekdccia
  • · Replies 18 ·
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18

Undergrad Do Cosmological Models Influence Quantum Field Theory?

  • KleinMoretti
  • · Replies 10 ·
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10

High School History of CMB, prediction of 1 in 100,000?

  • windy miller
  • · Replies 4 ·
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4

Undergrad Light curving around vortex simulating a black hole

  • addddb
  • · Replies 5 ·
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5

High School U.S. Solar Eclipses - Oct. 14, 2023 (Annular) & Apr. 08, 2024 (Total)

  • Borg
  • · Replies 68 ·
3
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68

High School Expansion of the Universe

  • petercl14
  • · Replies 9 ·
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9

Undergrad Determining stellar mass independent of its gravity

  • Ranku
  • · Replies 3 ·
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3

Undergrad Post Big Bang Gravity

  • Hyku
  • · Replies 11 ·
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11

Graduate Why Do Novas Emit Visible Light Despite Nuclear Reactions Producing Gamma Rays?

  • Brzohn
  • · Replies 2 ·
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2

High School NASA names asteroid "Hossi" after Sabine Hossenfelder

  • Swamp Thing
  • · Replies 3 ·
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3

Undergrad Why on Earth do we not see older stars close to us?

  • Martyn Arthur
  • · Replies 3 ·
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3

High School Solar Wind Particles, - reaching into Earth's magnetic field?

  • Mikael17
  • · Replies 1 ·
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1

High School Big Crunch in an infinite, symmetrical, Newtonian universe?

  • Pony
  • · Replies 10 ·
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10

High School What Are Quasi-Moons and How Do They Orbit Earth and the Sun?

  • Hornbein
  • · Replies 0 ·
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0

Undergrad Need help simplifying standard error formula for redshift

  • Rageuke
  • · Replies 3 ·
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3

Stargazing 'Devil' comet visible tonight 21.04.24

  • pinball1970
  • · Replies 8 ·
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8

High School How Do Radars in Space Prevent Signal Dispersion and Maintain Target Accuracy?

  • Field physics
  • · Replies 10 ·
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10

Stargazing What Could This Unidentified Moving Object in My Seestar S50 Sky Capture Be?

  • Skywave
  • · Replies 10 ·
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10

Undergrad Question about the big bang singularity

  • JuneSpring25
  • · Replies 13 ·
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13

Undergrad Questions about the accelerating Hubble expansion

  • Kairos
  • · Replies 36 ·
2
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36

Undergrad Sun shade on Earth ground, is it a straight line or a curved line?

  • applied-physics
  • · Replies 3 ·
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3

Undergrad Orientation of the Earth, Sun and Solar System in the Milky Way

  • fizixfan
  • · Replies 142 ·
5
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142

Undergrad The linear polarization and brightness of pulsars

  • ZX.Liang
  • · Replies 0 ·
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0

High School Recommendations for International Research Competitions

  • Andrii Dzygunenko
  • · Replies 4 ·
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4

Undergrad Where Are the Missing Black Holes in the Milky Way?

  • Vanadium 50
  • · Replies 87 ·
3
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87

High School How to use the Binary Mass Function for exoplanets?

  • Astroxzip
  • · Replies 4 ·
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4

Undergrad Has JWST solved the crisis in cosmology?

  • MrRobotoToo
  • · Replies 2 ·
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2

Undergrad How fast were distant galaxies moving?

  • kymner
  • · Replies 7 ·
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7

Undergrad Inflationary vs deflationary phase of Big Bang

  • BIGphysician
  • · Replies 10 ·
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10

Undergrad Meaning of the distance between galactic objects in GR

  • cianfa72
  • · Replies 9 ·
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9

Undergrad Speed of the umbra during eclipse vs rate of the Earth's rotation

  • imsmooth
  • · Replies 3 ·
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3

High School What is the actual shape of black holes?

  • souriyas
  • · Replies 4 ·
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4

Undergrad Increase frequency of solar eclipses

  • LightningInAJar
  • · Replies 6 ·
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6

High School Matter-antimatter asymmetry - a simple explanation?

  • JoaLi
  • · Replies 12 ·
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12

High School Things to try while watching the solar eclipse

  • jedishrfu
  • · Replies 48 ·
2
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48

Undergrad Expanding Universe without dark energy

  • takacszoltan87
  • · Replies 3 ·
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3

Undergrad Can there be slowly-falling accretion disks in black holes?

  • Suekdccia
  • · Replies 11 ·
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11