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

High School What's the farthest distance a star visible to the naked eye can still be seen?

  • eehiram
  • · Replies 19 ·
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19

Undergrad Mapping 21cm Neutral Hydrogen with Radio Telescope

  • JohnnyTheFox
  • · Replies 1 ·
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1

Graduate Entertain an idea from an ignorant student for a minute

  • Just some guy
  • · Replies 1 ·
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1

Graduate What can weak lensing be used for?

  • oldman
  • · Replies 2 ·
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2

Graduate Nucleosynthesis and Hubble expansion

  • emanaly
  • · Replies 10 ·
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10

Undergrad Searching for Intelligent Life: Understanding Radio Wave Filters

  • Entity
  • · Replies 3 ·
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3

Graduate Is the gravitational binding energy formula different for stars and galaxies?

  • kmarinas86
  • · Replies 2 ·
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2

Graduate Black holes, can we see them directly?

  • Chaos' lil bro Order
  • · Replies 6 ·
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6

Graduate Two black holes separated by more than one Schwarzschild radii

  • kmarinas86
  • · Replies 3 ·
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3

Graduate Cosmological geometries that may function as blackbodies

  • Loren Booda
  • · Replies 1 ·
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1

Graduate Is Speed Real and Who Has the Correct Frame of Reference in the Universe?

  • ukmicky
  • · Replies 3 ·
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3

Graduate Block Universe / Frozen Universe / Block Time

  • jrrship
  • · Replies 1 ·
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1

Graduate Entropy of Cosmological Event Horizon

  • Mike2
  • · Replies 28 ·
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28

Graduate Andromeda 5x bigger than previously thought.

  • Chaos' lil bro Order
  • · Replies 1 ·
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1

Graduate Do the L4 and L5 points travel in a geodesic?

  • kmarinas86
  • · Replies 1 ·
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1

Graduate Is the Three-Body Problem Unsolvable?

  • Saketh
  • · Replies 10 ·
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10

Where Can I Find Dates and Locations of Future Solar Eclipses?

  • gone gator
  • · Replies 1 ·
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1

Stargazing Leaving Telescope Out: Pros & Cons

  • Bob3141592
  • · Replies 5 ·
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5

Undergrad Why Is the Night Sky Dark If the Universe Is Infinite?

  • vincentm
  • · Replies 36 ·
2
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36

Graduate Universe Was Born in a Black Hole?

  • pivoxa15
  • · Replies 7 ·
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7

High School Mystery of the Bright Green Meteor: Is it Common?

  • interested_learner
  • · Replies 3 ·
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3

Graduate Gravity leaving a permanent indention?

  • Nexus555
  • · Replies 16 ·
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16

Stargazing High-Altitude Floating Space Telescope

  • sanman
  • · Replies 15 ·
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15

Graduate The universe should be billions of times brighter than the Milky Way?

  • kmarinas86
  • · Replies 4 ·
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4

Graduate SO(10) -> SU(3) x SU(2) x U(1) -inflation?

  • EL
  • · Replies 3 ·
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3

Graduate Reaching Other Stars, Colonizing Planets

  • sanman
  • · Replies 6 ·
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6

Graduate Why is a blackhole a one way ride

  • ukmicky
  • · Replies 15 ·
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15

Graduate Is the Concept of a Self-Replicating Unmanned Spacecraft Feasible?

  • {~}
  • · Replies 3 ·
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3

Undergrad Ratio of Orbital Distance to Transit Time

  • Panda
  • · Replies 4 ·
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4

High School What is Gravity? Understanding Its Role in Universe Formation

  • kleinma
  • · Replies 42 ·
2
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42

Graduate Evidence for a flat universe vs. circular logic

  • kmarinas86
  • · Replies 6 ·
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6

Undergrad Why Don't Black Holes Absorb Hawking Radiation?

  • Swapnil
  • · Replies 15 ·
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15

Undergrad Unraveling the Mysteries of Jupiter's Auroras

  • Baiji
  • · Replies 2 ·
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2

Graduate Where Can I Find Tutorials on Orbital Elements Perturbations?

  • dagmare
  • · Replies 1 ·
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1

Graduate Calculating the Radius of a Neutron Star

  • sammyz
  • · Replies 3 ·
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3

High School Theories and the begining of universe

  • navneet1990
  • · Replies 5 ·
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5

Graduate White Dwarf + Hydrogen Gas: Can It Revive Fusion?

  • El Nexus
  • · Replies 2 ·
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2

Undergrad Where should I begin with Astrophysics?

  • Bart
  • · Replies 41 ·
2
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41

High School The Sun Exploding: Effects on Earth

  • Glynis
  • · Replies 2 ·
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2

Undergrad Finding the Exact Time of Alignment of Earth, Sun and Center Sun

  • osirisisis
  • · Replies 10 ·
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10

High School Season Indicators: Know When Seasons Start & End

  • navneet1990
  • · Replies 16 ·
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16

Graduate What Are the Least Researched Topics in Observational Astrophysics?

  • moonquark
  • · Replies 6 ·
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6

Undergrad What Factors Affect the Color of a Star from Earth?

  • ranger
  • · Replies 3 ·
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3

Undergrad Can Gravity Explain the Tilt of Mars and Neptune?

  • krateesh
  • · Replies 10 ·
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10

High School How Can I Identify Constellations in the Night Sky?

  • mubashirmansoor
  • · Replies 6 ·
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6

Graduate How does the cosmological event horizon change the matter density?

  • Mike2
  • · Replies 1 ·
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1

Undergrad Speed of Gravity: Is It As Fast As Light?

  • TheMuses
  • · Replies 5 ·
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5

High School What Are Tidal Forces and How Do They Affect Different Bodies?

  • Zeit
  • · Replies 4 ·
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4

Undergrad Why Symmetry of Tides on Earth (influenced by moon, sun)

  • Ouabache
  • · Replies 3 ·
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3
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2

Graduate Mysteries of White Dwarf Formation: Massive Diamonds Inside?

  • Kitten Kaboodle
  • · Replies 4 ·
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4

Undergrad Where Can I Find a Comprehensive Database of Supernovae?

  • Andre
  • · Replies 11 ·
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11

High School Find the error in this paragraph about physics

  • 8parks11
  • · Replies 5 ·
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5

The Way Back to Your Universe Test

  • Evo
  • · Replies 15 ·
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15

Undergrad Siobhan Morgan's cosmology calculator has a new url

  • marcus
  • · Replies 5 ·
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5

High School Coordinate conversion calculator

  • big man
  • · Replies 2 ·
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2

Graduate Could Parallel Universes Be Created by Colliding Branes?

  • ptalar
  • · Replies 1 ·
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1

Undergrad How do we know how much hydrogen the sun has?

  • ranger
  • · Replies 3 ·
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3

Water Flows on Mars: What We Make of This Article

  • Azael
  • · Replies 11 ·
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11

High School .Is Water on Mars? Colonization: Frozen or Sent Men?

  • Integral
  • · Replies 18 ·
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18

High School Are There Infinite Earths in Infinite Space?

  • ||spoon||
  • · Replies 13 ·
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13

Undergrad Space Exploration and its effect on the Earth's Oxygen supply: I have a question

  • SAPierce2006
  • · Replies 15 ·
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15

Graduate Relativistic effects on interior of our sun?

  • chemisttree
  • · Replies 5 ·
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5

High School Just a little question on orbits.

  • Delzac
  • · Replies 9 ·
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9

MySpace Group Hacked And Deleted

  • zoobyshoe
  • · Replies 10 ·
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10

Undergrad How does gravity affect rotation?

  • Kirl
  • · Replies 3 ·
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3

Undergrad Random MOND theory / dark matter question(possibly really easy to answer)

  • lampshade
  • · Replies 4 ·
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4

Graduate Understanding Friedmann Equations Equation of State: Step-by-Step Walkthrough

  • parsifal
  • · Replies 2 ·
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2

Undergrad How can a star turn into a black hole, with the law of conservation of mass?

  • ilikefun411
  • · Replies 4 ·
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4

Stargazing Fixing Vertical Flipping in Prismatic Telescopes: A Troubleshooting Guide

  • [AFT]
  • · Replies 3 ·
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3

Undergrad Why does Jupiter have more gravity than its density should allow?

  • Jota
  • · Replies 9 ·
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9

Graduate Questions on the Movement of Stars

  • stardrop
  • · Replies 3 ·
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3

Undergrad Do hypernova events really exist, is there any proof for one existing?

  • Wellsi
  • · Replies 13 ·
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13

Graduate End of the Sky: Is There a Limit?

  • chandubaba
  • · Replies 6 ·
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6

Graduate Is Carlos Barcelo's Research Redefining Cosmology and Gravity?

  • Chronos
  • · Replies 52 ·
2
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52

Graduate Can we hit black hole's surface without dying?

  • chandubaba
  • · Replies 21 ·
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21

Graduate White Dwarf Radii: Minimizing Total Energy

  • quasar987
  • · Replies 7 ·
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7

Graduate What effects do the collision of galaxies have on the solar system?

  • Vast
  • · Replies 7 ·
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7

High School Understanding Kepler's Laws and Parallax in Astronomy

  • Wellsi
  • · Replies 6 ·
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6

Graduate Dark Matter Evidence: Baryonic & Non-Baryonic

  • SupersonicMan
  • · Replies 13 ·
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13

Graduate Why Doesn't This Black Hole Emit X-rays?

  • Labguy
  • · Replies 1 ·
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1

Graduate Is the Axis of Evil still a valid feature in the CMB data?

  • Garth
  • · Replies 8 ·
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8

Graduate Could Multiple Stars Be Hiding in Eta Carinae's Nebula?

  • Wellsi
  • · Replies 2 ·
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2

Graduate Help wanted with accelerated expansion and gr

  • Rip
  • · Replies 21 ·
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21

Graduate Why Is the Chandrasekhar Limit Estimated with Unrealistic Assumptions?

  • quasar987
  • · Replies 3 ·
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3

Stargazing First up is M13, 20 exposures of 30 seconds

  • Brinx
  • · Replies 9 ·
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9

Graduate Scientific explanation of the Universe

  • Handsome_Dick
  • · Replies 8 ·
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8

Graduate Does G vary because of Mach's Principle?

  • Garth
  • · Replies 13 ·
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13

Graduate How Do Upcoming Surveys Constrain Cosmological Models and Dark Energy?

  • SupersonicMan
  • · Replies 3 ·
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3

Stargazing Telescope Advice for Military Employee in Middle East - $1000 - $2000

  • gqusaf
  • · Replies 7 ·
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7

Graduate Can Photons Emit Gravitons in the Absence of Black Holes?

  • .ultimate
  • · Replies 2 ·
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2

Undergrad Last edited by a moderator: May 2, 2017

  • hasman
  • · Replies 14 ·
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14

Graduate What would happen if two black holes collided?

  • ocalhoun
  • · Replies 2 ·
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2

Undergrad Uncovering the Composition of Space: A Scientific Explanation

  • nannoh
  • · Replies 11 ·
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11

Undergrad Are Black Holes Universal Recycling Bins?

  • Epircus
  • · Replies 15 ·
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15

Graduate The Possibility of Curved Spacetime, Black Holes, and Big Bang. .

  • cosmopot
  • · Replies 1 ·
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1

High School Far Side of Sun: Can Satellites View Opposite Side?

  • RJ Emery
  • · Replies 9 ·
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9

Graduate WMAP and Big Crunch: Is the Universe's Fate Sealed?

  • vincentm
  • · Replies 1 ·
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1

Graduate Can science and technology give us complete control over the universe?

  • octelcogopod
  • · Replies 2 ·
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2

Graduate Exploring Binary Pulsar Mechanics: Lagrangian Formulations

  • Logarythmic
  • · Replies 1 ·
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1