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

Graduate Intuition Behind Scale Invariance Power Spectrum

  • center o bass
  • · Replies 1 ·
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1

Graduate Penrose's cyclic universe - question

  • hammock
  • · Replies 2 ·
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2

Graduate Why isn't everything expanding in an expanding universe?

  • Happiness
  • · Replies 51 ·
2
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51

Insights Animating Black holes and Singularities - Comments

  • edguy99
  • · Replies 5 ·
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5

Graduate Killing vectors and momentum conservation

  • jcap
  • · Replies 13 ·
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13

Undergrad Does the Universe Have its Own Clock and Period?

  • Atlas3
  • · Replies 30 ·
2
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30

High School Proof that the moon is closer to Earth than the sun

  • Rabbani
  • · Replies 33 ·
2
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33

Undergrad Could you send an object into space completely without fuel?

  • rumborak
  • · Replies 18 ·
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18

High School Discover the Fascinating Rotations of the Moon | Gibraltar to Auckland Views

  • Andrew1955
  • · Replies 17 ·
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17

Graduate Inside the big bang were their other sub big bangs?

  • tlain123
  • · Replies 4 ·
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4

Graduate Does Chiral EM Asymmetry Imply Matter-Antimatter Asymmetry?

  • ohwilleke
  • · Replies 2 ·
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2

Graduate Relationship betwen ##Ω_k## and ##k##

  • Quarlep
  • · Replies 3 ·
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3

Graduate Expanding universe - some thoughts

  • Whitefire
  • · Replies 13 ·
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13

Graduate Universe density in Hyperbolic Universe

  • Quarlep
  • · Replies 14 ·
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14

Graduate Litterature on Statistical Homogeneity and Isotropy

  • center o bass
  • · Replies 1 ·
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1

Graduate Upper bound on the Inflation's e-foldings

  • Trifis
  • · Replies 3 ·
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3

Graduate CMB , Spherical Harmonics and Rotational Invariance

  • center o bass
  • · Replies 4 ·
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4

Graduate Referance Frame Calculating Newtonian Friedmann Equation

  • Quarlep
  • · Replies 18 ·
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18

Graduate What is the cause of space expansion in the universe?

  • Stephanus
  • · Replies 3 ·
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3

Graduate Question about gravitational waves, E modes

  • Frank Einstein
  • · Replies 1 ·
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1

Graduate General differential equation solution for Kepler Problem

  • Steve Jones
  • · Replies 4 ·
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4

Graduate How do galaxies die? Contradictions between two papers

  • Novanglus
  • · Replies 1 ·
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1

High School Question on Comet 67P tail in Rosetta image

  • ehilge
  • · Replies 12 ·
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12

Undergrad Distance Comparison: Converting 48 Distance Modulus to Meters

  • Kairos
  • · Replies 27 ·
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27

Undergrad Confirmation on the Effect of Solar Irradiance

  • ecastro
  • · Replies 7 ·
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7

Graduate Lyman Series Wavelengths - measurement standard?

  • neilparker62
  • · Replies 0 ·
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0

Graduate Universe from nothing, again....

  • Stephanus
  • · Replies 7 ·
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7

Graduate M31 halo paper - question on metallicity

  • jim mcnamara
  • · Replies 1 ·
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1

Graduate Can we be sure about there was nothing before big bang?

  • Lightermahn
  • · Replies 5 ·
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5

Graduate Galaxy Acceleration: Unraveling the Mysteries of Dark Energy

  • Stephanus
  • · Replies 10 ·
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10

Graduate Will the time will eventually stop like a snapshot?

  • Lightermahn
  • · Replies 2 ·
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2

High School Orbiting Eternally: Physics Q&A with Steven

  • Stephanus
  • · Replies 5 ·
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5

Graduate Compatibility of General Relativity with SO(3)

  • Ans
  • · Replies 3 ·
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3

Graduate In Need of Some (Measurable) Illumination

  • Dr Wu
  • · Replies 10 ·
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10

Graduate If space is curved, could it be detected

  • newjerseyrunner
  • · Replies 26 ·
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26

Graduate Is "heavy nothing" already infinite or is it expanding?

  • slatts
  • · Replies 7 ·
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7

Graduate Does the Universe Have a Preferred Frame of Reference?

  • Stephanus
  • · Replies 2 ·
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2

Graduate Is the mass of the universe finite (collection of objects)?

  • King Solomon
  • · Replies 53 ·
2
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53

Graduate Detecting the presence of other universes

  • Happiness
  • · Replies 10 ·
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10

Graduate Does Relativity Alter Our Perception of Galaxies?

  • Low-Q
  • · Replies 5 ·
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5

Graduate Boltzmann Brains: Are They Taken Seriously by Scientists?

  • RyanJones
  • · Replies 9 ·
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9

What will happen if our sun color blue?

  • Dr.ahmad adnan
  • · Replies 15 ·
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15

Graduate Can We See CMB Again If Universe Expands at a Constant Rate?

  • CassiopeiaA
  • · Replies 15 ·
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15

Graduate Radio astronomical receiving system

  • ansenko
  • · Replies 5 ·
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5

Graduate Can Dark Energy Be Described as a Force?

  • Quarlep
  • · Replies 3 ·
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3

Graduate Time and Universe: Shedding Light on Dark Energy & Dark Matter

  • wolram
  • · Replies 1 ·
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1

Graduate What's the universe radius function

  • Quarlep
  • · Replies 10 ·
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10

Graduate Earth's velocity wrt CMB gives the centre of the universe?

  • Happiness
  • · Replies 3 ·
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3

Undergrad How can I know if two stars came from the same cluster?

  • Frank Einstein
  • · Replies 4 ·
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4

Graduate Measuring Gravitational Redshift due to Galaxies without GR

  • quantumfoam
  • · Replies 4 ·
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4

Graduate How Far Can We Detect Faint Celestial Objects Near Our Solar System?

  • Dr Wu
  • · Replies 6 ·
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6

Graduate Baryon number conservation in early universe when T<m

  • karlzr
  • · Replies 8 ·
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8

Undergrad Find Radial Velocity of Galaxies

  • Quarlep
  • · Replies 3 ·
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3

Graduate What if expansion rate of a universe is the speed of light?

  • Burtay Mutlu
  • · Replies 8 ·
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8

Graduate Explaining Universe Expansion Through Gravity & 3D Geometry

  • Scott444
  • · Replies 6 ·
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6

Undergrad Is Earth the Center of the Universe?

  • ScienceIsFun
  • · Replies 6 ·
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6

Graduate Cosmic strings account for primordial SMBH production?

  • Chronos
  • · Replies 2 ·
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2

Graduate CMB polarization: the E and B modes

  • fairy._.queen
  • · Replies 11 ·
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11

Graduate Very Large Halo Around the Andromeda Galaxy

  • Tanelorn
  • · Replies 3 ·
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3

Stargazing Can I Make My Own 8 Telescope with These Required Instruments?

  • Harshil
  • · Replies 2 ·
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2

Graduate Can time be a periodic function in GRFE?

  • Atlas3
  • · Replies 15 ·
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15

Graduate If the universe has a spin, was it causing the similar

  • Burtay Mutlu
  • · Replies 1 ·
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1

Undergrad Calculating Star and Planet Positions in the Night Sky: A Mathematical Approach

  • Harshil
  • · Replies 5 ·
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5

Undergrad Is the expansion of the universe similar to an explosion?

  • thetexan
  • · Replies 10 ·
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10

High School How much energy radiates from Jupiter?

  • Ans
  • · Replies 4 ·
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4

Graduate Universe: Is it Nothing? | Steven

  • Stephanus
  • · Replies 7 ·
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7

Undergrad If we consider the universe as bounded but infinite

  • Atlas3
  • · Replies 13 ·
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13

Undergrad Gravity moving toward the center of the Sun?

  • brains3234
  • · Replies 20 ·
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20

Graduate How does a particle's kinetic energy vary with a(t)?

  • Buzz Bloom
  • · Replies 33 ·
2
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33

Is there any physicists i could email?

  • veronicap
  • · Replies 2 ·
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2

Undergrad Expansion of space in our neighborhood

  • virgil1612
  • · Replies 9 ·
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9

Graduate Primordial Neutrinos: Density & Temperatures

  • Buzz Bloom
  • · Replies 16 ·
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16

Graduate Can the expansion of space affect the speed of light?

  • Ghostcrown
  • · Replies 4 ·
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4

Graduate Uncovering Krauss's Flaws: Analysis of Claims in a Universe from Nothing

  • Thomas Moore
  • · Replies 13 ·
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13

Graduate Gamow peak and nuclear reaction rate

  • wieblinger
  • · Replies 2 ·
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2

High School What Would Happen if I Threw My Watch into a Black Hole?

  • Emmanuel_Euler
  • · Replies 10 ·
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10

Graduate Farthest Object in Universe & Multiverse | Steven

  • Stephanus
  • · Replies 12 ·
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12

Graduate Lightcone 1.0 basic redshift article development

  • Mordred
  • · Replies 14 ·
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14

Graduate Big Bang Temperature - What Was It?

  • Stephanus
  • · Replies 6 ·
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6

Graduate Would a supermassive black hole explode?

  • newjerseyrunner
  • · Replies 5 ·
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5

Stargazing Problem in making a small refracting Telescope

  • Ibrahim Hany
  • · Replies 3 ·
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3

Graduate Is Dark matter an optical illusion?

  • Zimbler Igor
  • · Replies 1 ·
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1

High School Are there any "Polar" solar system structures?

  • Jimster41
  • · Replies 10 ·
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10

Undergrad Am I moving, or is space moving?

  • iDimension
  • · Replies 5 ·
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5

Graduate Calculating the event horizon of black holes.

  • William Henley
  • · Replies 5 ·
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5

Undergrad Redshift, Earth's orbital speed, and the speed of light

  • iantresman
  • · Replies 1 ·
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1

Undergrad Using the Suns gravity for propulsion

  • Scaledriver
  • · Replies 17 ·
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17

Stargazing Why is there no Hubble-like telescope on the International Space Station?

  • Bob__
  • · Replies 6 ·
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6

Graduate Predicting angle of deflection of light

  • William Henley
  • · Replies 7 ·
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7

Graduate How many cubic planck lengths are in the observable universe?

  • Alex299792458
  • · Replies 7 ·
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7

Undergrad Loss of mass of an object falling through air

  • Sumit Adhikari
  • · Replies 8 ·
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8

High School Conservation of momentum of collision

  • sander2798
  • · Replies 2 ·
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2

Graduate Are there multiverse models with infinte regress?

  • Philm
  • · Replies 1 ·
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1

Graduate Simple no-pressure cosmic model gives meaning to Lambda

  • marcus
  • · Replies 105 ·
4
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105

New Horizons Sees First Features on Pluto

  • Drakkith
  • · Replies 13 ·
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13

Graduate Observational difference between OS and FLRW

  • wabbit
  • · Replies 27 ·
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27

Graduate Can NASA's Impossible EM Drive Revolutionize Space Travel?

  • jimmylegss
  • · Replies 2 ·
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2

Graduate Do Dark matter and Dark energy interact?

  • wolram
  • · Replies 1 ·
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1

Graduate Mass of a galaxy without dark matter and with dark matter

  • Quarlep
  • · Replies 37 ·
2
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37
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6