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 Is the Drake Equation Overestimating Intelligent Life in the Universe?

  • Stu21
  • · Replies 18 ·
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18

Graduate Could a Star Collapse into a Quark Star Instead of a Black Hole?

  • AbsoluteZer0
  • · Replies 3 ·
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3

High School Looking further and further into the past?

  • pwdrmntainski
  • · Replies 2 ·
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2

Graduate Fields permeating spacetime - aether?

  • jnorman
  • · Replies 3 ·
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3

High School What Is the Diameter of the Observable Universe?

  • Myslius
  • · Replies 9 ·
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9

Undergrad Does time move faster while measured from space or from earth?

  • Rorkster2
  • · Replies 10 ·
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10

Graduate If the moon was vapourised, would it recondense or get blown away by solar wind?

  • jetwaterluffy
  • · Replies 8 ·
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8

Stargazing How Do I Choose the Right Optical Lenses for Building a Telescope?

  • DrCy
  • · Replies 4 ·
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4

Stargazing Problem about calculating focal length of a telescope

  • Blacky&Imy
  • · Replies 2 ·
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2

Undergrad Unraveling the Chaos: Examining the Birth and Behavior of the Universe

  • Grimstone
  • · Replies 24 ·
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24

Undergrad Space Time Expansion: How Galaxies Formed

  • Brook
  • · Replies 21 ·
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21

Graduate Is Newton's Law a Result of Constant Volumetric Expansion?

  • MDEarl
  • · Replies 19 ·
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19

Graduate Interstellar Medium Around Sol / Interstellar Ramscoop

  • MattRob
  • · Replies 7 ·
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7

Graduate Is eternal inflation possible in LQC?

  • MathematicalPhysicist
  • · Replies 23 ·
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23

Undergrad 10 light years but destroyed 6000 years ago?

  • heartyface
  • · Replies 7 ·
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7

Graduate Dark matter/Dark antimatter Asymmetry?

  • alemsalem
  • · Replies 6 ·
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6

Graduate How is energy/matter density distributed through the universe?

  • Rorkster2
  • · Replies 4 ·
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4

Graduate Dark Matter: Interacting Particles & Gravitational Forces

  • someGorilla
  • · Replies 3 ·
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3

Undergrad What is the width of the Lagrange points?

  • CowedbyWisdom
  • · Replies 1 ·
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1

Graduate How much mass does 'Dark Matter' and 'Nothing' (empty space) have?

  • Rorkster2
  • · Replies 6 ·
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6

Graduate Is the proper distance the shortest distance in FLRW universe?

  • andrewkirk
  • · Replies 7 ·
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7

Graduate Why Doesn't Dark Energy Expand Galaxies?

  • g.lemaitre
  • · Replies 30 ·
2
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30

Undergrad Good Introductory Book/Article to Dark Energy?

  • charmander
  • · Replies 4 ·
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4

Graduate Proposed dark matter detector - how does it work?

  • Roo2
  • · Replies 11 ·
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11

Graduate Can Space Expand Faster Than the Speed of Light?

  • DARKSYDE
  • · Replies 10 ·
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10

Undergrad Do scientists know why planets orbit stars on the same dimentional plane?

  • Rorkster2
  • · Replies 4 ·
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4

Graduate Why Doesn't the Comoving Hubble Length Always Increase?

  • alialice
  • · Replies 9 ·
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9

Graduate Size/Mass of a planet needed in order to have a molten core or a magnetic field?

  • jarroe
  • · Replies 3 ·
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3

Undergrad Speed Of Light In Relation To The Size Of The Universe

  • CowedbyWisdom
  • · Replies 8 ·
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8

Undergrad When did they discover the Gas Giants were fluid?

  • mopc
  • · Replies 4 ·
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4

Graduate Kepler's Equation and its choices

  • solarblast
  • · Replies 9 ·
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9

High School How many degrees of view is cosmic microwave background?

  • Rorkster2
  • · Replies 3 ·
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3

Graduate Question about the expansion of space.

  • weinie
  • · Replies 23 ·
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23

High School How do you define a planet's rotation?

  • skiller
  • · Replies 12 ·
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12

Graduate Pulsar Spectrum: The Mystery of Neutron Star's Black Body Emission Revealed

  • alialice
  • · Replies 2 ·
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2

Graduate Need Help Writing a Sci-Fi Film Plot with Astronomy

  • closecall17
  • · Replies 7 ·
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7

Graduate Did all 10^80 particles exist after the first 3 minutes?

  • g.lemaitre
  • · Replies 15 ·
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15

Undergrad What happens to you if you get pulled into a black hole?

  • DrPhy
  • · Replies 26 ·
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26

Graduate How is it possible to live past the event horizon?

  • spacetimedude
  • · Replies 19 ·
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19

Graduate Creating Artificial Gravity for Spacecraft Travel

  • Robert_K
  • · Replies 5 ·
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5

High School Night sky and supernova questions

  • Government$
  • · Replies 9 ·
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9

Undergrad How is molecular hydrogen detected?

  • JDoolin
  • · Replies 95 ·
4
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95

Undergrad Angular momentum and eccentricity

  • Alexrey
  • · Replies 2 ·
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2

Graduate Life in the process of universe: the goal or just a side effect?

  • Graal
  • · Replies 17 ·
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17

Graduate Is the universe 13.7 Billion years old? There seems to be a contradiction

  • surajt88
  • · Replies 48 ·
2
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48

Graduate An Infinite Lapse of Time is Impossible and Unscientific

  • james.goetz
  • · Replies 43 ·
2
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43

High School Pluto's color changes as it makes its closest approach?

  • jarroe
  • · Replies 1 ·
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1

Jumping into a earthcenter tunnel

  • schiz0ai
  • · Replies 4 ·
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4

Undergrad Speed through the universe we are moving?

  • jarroe
  • · Replies 4 ·
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4

Undergrad Is the Expanding Universe Affecting Our Solar System?

  • Ikon Rahu
  • · Replies 37 ·
2
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37

Graduate What is the system of angular units used by astronomers of Venus?

  • kapella
  • · Replies 2 ·
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2

Graduate Could we see Earth 75.2 years ago using light from a supermassive black hole?

  • kevpatts
  • · Replies 6 ·
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6

High School What Were the Two Bright Yellow Lights in the Sky on July 10th?

  • Aero51
  • · Replies 4 ·
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4

Graduate Can Negative Changes in Entropy Occur in the Universe?

  • Aero51
  • · Replies 26 ·
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26

High School Is the Universe Really Flat and What Lies Above or Below the Earth?

  • Erik B
  • · Replies 3 ·
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3

Undergrad Is this a misleading representation of boomerang results

  • jerusalem
  • · Replies 56 ·
2
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56

Graduate CERN particle announcement related to dark matter / energy?

  • Lino
  • · Replies 6 ·
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6

Graduate Why Are Galaxies Rushing Apart According to Weinberg's First Three Minutes?

  • g.lemaitre
  • · Replies 5 ·
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5

Graduate Other dimensions have been proven .

  • jarroe
  • · Replies 15 ·
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15

Graduate Measuring the Accuracy of EM Spectrum Shift: Red vs Blue

  • Bjarne
  • · Replies 11 ·
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11

Undergrad Calculating orbits of moons, when both the planet and star are involved.

  • sydan
  • · Replies 8 ·
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8

Graduate How Flat is Our Universe Really?

  • marcus
  • · Replies 5 ·
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5

Graduate Does a Space Warp Bubble Move Through Space or Does Space Move Around It?

  • jarroe
  • · Replies 3 ·
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3

Graduate Questioning Hubble's Law: Does the Expanding Universe Theory Hold Up?

  • khurramc
  • · Replies 3 ·
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3

Graduate Cosmological expansion vs. stretching

  • Neuroglider
  • · Replies 36 ·
2
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36

Graduate Dark energy related to 10-dimensional universe

  • vened
  • · Replies 2 ·
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2

Graduate Could the Universe Have Regions of Expansion and Collapse?

  • coolcalx
  • · Replies 27 ·
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27

Graduate Post big bang matter/energy distribution

  • jarroe
  • · Replies 2 ·
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2

Graduate Can black holes be disintegrated from a sufficiently powerful explosion?

  • Bararontok
  • · Replies 34 ·
2
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34

Graduate Imposssible to see light that left a star 13.4 billion yrs ago

  • aboro
  • · Replies 20 ·
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20

Graduate Dark Matter - How strong is it at a galaxy periphery?

  • Bjarne
  • · Replies 1 ·
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1

Graduate Why is a gravitational field negative energy ?

  • andrewkirk
  • · Replies 5 ·
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5

Undergrad Gravity in the Universe: Is There a Weakest Force?

  • Lino
  • · Replies 10 ·
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10

Undergrad Size of the Universe? I'm confused.

  • TheSwamper
  • · Replies 7 ·
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7

Graduate Would the universe be the same if it was reset?

  • ResolutE
  • · Replies 27 ·
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27

Undergrad Calculating distance from redshift

  • chris1969
  • · Replies 6 ·
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6

Graduate In what sense is the standard model enormously successful

  • g.lemaitre
  • · Replies 14 ·
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14

Undergrad Dark matter is the thread connecting galaxy clusters

  • arabianights
  • · Replies 3 ·
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3

Graduate Plotting planetary movements through space

  • Rakky
  • · Replies 8 ·
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8

Graduate What is the universe itself made of beyond its contents?

  • WMan
  • · Replies 7 ·
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7

Is This CM Book by Roy on Orbital Motion?

  • solarblast
  • · Replies 2 ·
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2

Graduate Is Our Universe Just a Balloon in an Infinite Matrix?

  • megacal
  • · Replies 2 ·
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2

Graduate Explosion picture: most common mistake

  • marcus
  • · Replies 2 ·
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2

Graduate Did a Higgs Boson trigger the big bang?

  • Magnus Warhol
  • · Replies 6 ·
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6

Graduate Calculating the Size of the Universe

  • denism
  • · Replies 32 ·
2
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32

Undergrad Critical density in our expanding universe

  • Positralino
  • · Replies 4 ·
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4

Graduate Could dark matter be invisible bound states of ordinary matter or ehm, aliens?

  • Antti
  • · Replies 1 ·
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1

Graduate Is the Universe Spinning? | General Relativity

  • Always curious
  • · Replies 31 ·
2
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31

Graduate Is the Sun's luminosity in specific filters greater than its overall luminosity?

  • StarDweller
  • · Replies 1 ·
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1

Undergrad Venus Spinning Slower Than Thought

  • Andre
  • · Replies 25 ·
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25

Graduate Eight steps to the understanding the CEH

  • marcus
  • · Replies 1 ·
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1

Graduate Why is the Universe electrically neutral?

  • lpetrich
  • · Replies 2 ·
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2

Graduate Exploring the Properties of Gravitational Waves: Evidence, Structure, and Speed

  • SinghRP
  • · Replies 6 ·
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6

Undergrad What if time is not linear? Can it be experienced out of sequence?

  • cdot
  • · Replies 7 ·
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7

Graduate Calculating Force and Energy Requirements for a Reactionless Drive in Space

  • MIKESMIND
  • · Replies 4 ·
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4

Graduate Higgs & Inflaton: Does New Boson Discovery Change Anything?

  • skydivephil
  • · Replies 7 ·
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7

Undergrad Is space really absolutely nothing?

  • NeptuniumBOMB
  • · Replies 20 ·
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20

Graduate What Does Density Contrast in the Universe Mean in the Context of Chaplygin Gas?

  • kptsilva
  • · Replies 10 ·
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10

Graduate What is absolute in this universe?

  • Nikhilb
  • · Replies 24 ·
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24

Undergrad Distance time travels per second

  • Pricey
  • · Replies 3 ·
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3