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 Cosmic Horizon and Surface of Last Scattering Question

  • Salamon
  • · Replies 4 ·
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4

Earth's axial tilt and the shadow from the Sun

  • Rangertab1
  • · Replies 8 ·
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8

Undergrad Functions for properties of stars and their planets

  • Schilcote
  • · Replies 6 ·
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6

Graduate Question about eddington luminosity

  • seeker7
  • · Replies 1 ·
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1

High School Consequence of light pointing towards a blackhole

  • cooper607
  • · Replies 3 ·
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3

Undergrad Shooting images through window pane glass

  • solarblast
  • · Replies 3 ·
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3

Graduate Form of Friedman eqn with Λ curvature constant

  • marcus
  • · Replies 12 ·
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12

I've finally accept that the universe is unimaginable

  • MathJakob
  • · Replies 6 ·
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6

Graduate Mass Luminosity relation doesn't hold true when applied to actual data

  • wolf1728
  • · Replies 4 ·
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4

Graduate Super novae mechanics - how does it work?

  • lavinia
  • · Replies 5 ·
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5

Graduate Where is the edge of the universe

  • Adrian07
  • · Replies 133 ·
5
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133

High School Why does everything in the Universe form a ball or Sphere?

  • blackstar5000
  • · Replies 6 ·
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6

Graduate Intergalactic message exercises (for LightCone tutorial)

  • marcus
  • · Replies 7 ·
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7

Graduate Does Dark Energy break the Conservation of Energy?

  • typical guy
  • · Replies 2 ·
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2

High School What is the shape of a Black Hole?

  • blackstar5000
  • · Replies 3 ·
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3

Graduate What happens to EM waves outside the universe?

  • yoyopizza
  • · Replies 14 ·
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14

Graduate Does Distant Starlight Become Coherent Upon Reaching Earth?

  • brianhurren
  • · Replies 8 ·
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8

Graduate Is There a Universal Redshift Formula for Arbitrary Spacetime Metrics?

  • tom.stoer
  • · Replies 52 ·
2
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52

Graduate Can a Message Travel Faster Than Light to Reach a Distant Galaxy?

  • marcus
  • · Replies 8 ·
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8

Graduate Fine-tuned Universe; let's find out

  • SeriousQuest
  • · Replies 3 ·
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3

Graduate Switch to scale factor time (universe its own clock)

  • marcus
  • · Replies 10 ·
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10

Graduate Exotic atoms hold clues to unsolved physics puzzle at the dawn of the

  • julcab12
  • · Replies 1 ·
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1

Graduate Current State of the Big Freeze end of the Universe Theory.

  • raluu
  • · Replies 2 ·
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2

Graduate Calculation of Universal Constants for Life-Sustaining Universe

  • SeriousQuest
  • · Replies 4 ·
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4

Undergrad What is the shape of the known universe?

  • dr1p
  • · Replies 29 ·
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29

Graduate The most simple explanation for origination of spiral galaxies?

  • Edward Solomo
  • · Replies 4 ·
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4

Graduate Can Technology Allow Us to Travel Back in Time and Create Ourselves?

  • mtasquared
  • · Replies 4 ·
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4

Graduate Which: scale or years? as parameter of change

  • marcus
  • · Replies 20 ·
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20

Undergrad Calculate LST: Uncover the Mystery of 100.46

  • mishima
  • · Replies 13 ·
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13

Undergrad Example to make clear the difference between specific intensity and fl

  • alkmini
  • · Replies 2 ·
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2

Graduate Critical Density and the expanding universe

  • Matt Walker
  • · Replies 1 ·
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1

Undergrad The Ecliptic and the Galactic Planes

  • EskWIRED
  • · Replies 4 ·
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4

Graduate Black hole evaporation, where does it all go?

  • Geordie Ross
  • · Replies 4 ·
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4

Graduate What are N-Body Simulations and how do they relate to matter and dark matter?

  • Madster
  • · Replies 3 ·
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3

Graduate Imaginary Time: Parallel Universes & Mass?

  • tmv3v
  • · Replies 1 ·
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1

Graduate Is the speed of light constant in a vacuum?

  • Thomas1989
  • · Replies 1 ·
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1

Graduate Was the flow of time slower in the early universe?

  • jalak7
  • · Replies 20 ·
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20

Undergrad Redshifts & Hubble: How Do We Know Galaxies are Moving?

  • La_Mettrie
  • · Replies 7 ·
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7

Graduate James Bond and the true value of the cosmological curvature constant

  • marcus
  • · Replies 5 ·
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5

Graduate To stir the pot Post inflationary period

  • spark802
  • · Replies 8 ·
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8

Graduate Universe Shape: Flat or Hyperbolic? Cosmologists Weigh In

  • DiracPool
  • · Replies 33 ·
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33

Undergrad Is Dark Energy Truly Real? What Do Scientists Know and Who Rejects It?

  • M. next
  • · Replies 11 ·
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11

Graduate Dark Matter Evidence: Non-Baryonic Cosmology

  • Chronos
  • · Replies 6 ·
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6

Graduate What's the role of stellar interference in redshifts?

  • Neuvotonian
  • · Replies 6 ·
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6

Graduate Can Black Holes Consume Light Without Increasing in Mass?

  • Jonaset
  • · Replies 5 ·
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5

Graduate How to derive dark energy density from Jorrie's Hubble radius limit

  • marcus
  • · Replies 9 ·
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9

Undergrad Why Consider Dark Matter Over New Space for Universe Expansion?

  • mrxyz
  • · Replies 3 ·
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3

Graduate Could Dark Energy Originate from Gravity Waves?

  • skydivephil
  • · Replies 3 ·
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3

Graduate How to measure the location of Gamma ray burst ?

  • goldfishCUPHY
  • · Replies 3 ·
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3

Graduate Lightcone 1.0 tabular cosmology calculator

  • marcus
  • · Replies 4 ·
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4

Graduate Flat universe and big bang theory

  • vattoman
  • · Replies 11 ·
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11

Undergrad Does gravity affect time on different celestial objects

  • alfnzo
  • · Replies 3 ·
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3

Graduate Gravitational potential and the past

  • h_cat
  • · Replies 7 ·
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7

Graduate Cosmo calculators with tabular output

  • marcus
  • · Replies 76 ·
3
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76

High School Saturn hurricane spotted by Cassini

  • Mordred
  • · Replies 2 ·
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2

Graduate Gods Lego, what are the chances?

  • Rcbs
  • · Replies 8 ·
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8

Graduate Seeking clarification on singularity at genesis

  • acesuv
  • · Replies 6 ·
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6

Graduate Cosmological constant and vacuum energy

  • ftr
  • · Replies 7 ·
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7

Graduate Print a history of the universe you'd like to share

  • marcus
  • · Replies 26 ·
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26

Graduate Can a Black Hole's High Entropy State Coexist with Supercondensed Matter?

  • Double-Slit
  • · Replies 14 ·
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14

Graduate Is there a reason to believe in a limited variety of dark matter?

  • mrspeedybob
  • · Replies 2 ·
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2

Graduate Does angular diameter distance vary with composition of the Universe?

  • ck99
  • · Replies 4 ·
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4

Graduate White Hole in Universe: Is the Center Expanding?

  • nil1996
  • · Replies 3 ·
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3

High School Uncovering the Mystery: Comparing the Russian Meteor to the Tunguska Event

  • DFTBA
  • · Replies 2 ·
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2

Graduate Can the fabric of space ripple like a gentle wave in the ocean?

  • mannygonzales1
  • · Replies 1 ·
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1

High School Universe Expansion: Understanding the Concept

  • Abscissas
  • · Replies 8 ·
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8

Undergrad Can Radiation from Black Holes Travel Faster than Light?

  • lostinaworld
  • · Replies 13 ·
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13

Undergrad Gravitational Lensing vs Gravitational Microlensing

  • sfbsoccer25
  • · Replies 1 ·
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1

Undergrad Does Dark Matter Really Exist and What Evidence Supports Its Composition?

  • Astro-Anouar
  • · Replies 3 ·
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3

Graduate Linear vs non linear matter power spectrum

  • Jip
  • · Replies 5 ·
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5

High School Expanding Universe: What Does it Mean?

  • Xidike
  • · Replies 21 ·
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21

High School Where is the universe expanding?

  • nil1996
  • · Replies 2 ·
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2

Graduate Is Loop Quantum Multiverse a Viable Theory?

  • skydivephil
  • · Replies 5 ·
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5

Stargazing Using the Celestron C90 telescope

  • guitarphysics
  • · Replies 9 ·
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9

Undergrad Distance modulus and redshift Ia supernovae Catalog

  • kalabarta
  • · Replies 1 ·
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1

Graduate Solar and geomagnetic field interaction with or without solar wind

  • rewtnode
  • · Replies 7 ·
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7

Undergrad If the universe is infinite, then the big bang theory can't be correct

  • jaydnul
  • · Replies 2 ·
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2

Graduate How Do We Calculate the Age and Distance of Light in the Universe?

  • Crazymechanic
  • · Replies 4 ·
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4

Graduate Can Choices Create Parallel Universes in an Infinite Cosmos?

  • Astro-Anouar
  • · Replies 30 ·
2
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30

High School Time taken for earth to orbit the sun?

  • Tuvshee
  • · Replies 12 ·
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12

High School Jeans Mass Formula - Find Solution Now!

  • shounakbhatta
  • · Replies 2 ·
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2

Graduate LambdaCDM inflation model dependancies

  • Mordred
  • · Replies 5 ·
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5

Graduate Question regarding maximum accretion of black holes

  • can't.do.phys
  • · Replies 1 ·
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1

Undergrad Question Regarding the Orbit of Comets

  • Yosty22
  • · Replies 3 ·
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3

Graduate Inflationary paradigm in trouble after Planck2013 ? I doubt it, but

  • mitchell porter
  • · Replies 34 ·
2
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34

Undergrad Did the Chelyabinsk meteor really explode ?

  • Crikey
  • · Replies 4 ·
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4

Graduate Do Schwarzschild Black Holes exist?

  • EskWIRED
  • · Replies 11 ·
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11

Graduate Jeans instabiity & gravitational collapse

  • shounakbhatta
  • · Replies 3 ·
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3

Graduate What Determines the Precise Chronology of the Universe?

  • DiracPool
  • · Replies 23 ·
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23

Graduate Cosmological redshift interpretation

  • johne1618
  • · Replies 10 ·
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10

Graduate Why are scientists puzzled at the time of the universe that we are in?

  • student34
  • · Replies 2 ·
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2

High School Moon's Orbit: The Science Behind Its Path

  • Ahmed Samra
  • · Replies 6 ·
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6

Undergrad Can this planet have an ocean of water?

  • willstaruss22
  • · Replies 11 ·
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11

Undergrad Quasar is a huge source of energy

  • Astro-Anouar
  • · Replies 2 ·
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2

Graduate What do positrons have to do with dark matter?

  • DiracPool
  • · Replies 2 ·
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2

NASA SDO: 3 Years of Solar Images

  • nsaspook
  • · Replies 1 ·
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1

Graduate Specific question about infinite size and age of the universe

  • seeker7
  • · Replies 13 ·
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13

Graduate How can two Black holes fusion and consist a supermassive Black Hole

  • Astro-Anouar
  • · Replies 7 ·
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7

Graduate Could absolute motion exist in higher dimensions, if they exist?

  • Chemastro
  • · Replies 1 ·
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1

Graduate Speed of light in a dark matter medium

  • anorlunda
  • · Replies 7 ·
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7