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 How Would a Halved Earth Mass Affect the Moon's Rotation Period?

  • nmsurobert
  • · Replies 2 ·
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2

Graduate Is the location of galaxy X in the universe constant?

  • HZY
  • · Replies 22 ·
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22

Lunar super eclipse Sept. 27th. 2015

  • hagar
  • · Replies 49 ·
2
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49

High School Find 1.25" Focuser for 8" Newtonian Telescope

  • zeriodpeezeriod
  • · Replies 2 ·
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2

Graduate Negative energy is repulsive, but PE is negative, so?

  • nomadreid
  • · Replies 2 ·
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2

High School Need reliable resources on basic astronomy and quantum physics

  • CrackerMcGinger
  • · Replies 12 ·
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12

Graduate How to measure CMB anisotropies *In Practice*

  • astrolollo
  • · Replies 2 ·
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2

Graduate Pre-Big Bang Environment & Rules: Insights on the Known Laws of the Universe

  • michaeljmj
  • · Replies 15 ·
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15

Graduate Does Gravity Gravitating Alter Cosmology?

  • wolram
  • · Replies 20 ·
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20

Graduate Frame of reference: grade 2n vs. grade 2n-1

  • eaglechief
  • · Replies 2 ·
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2

High School What Is the True Speed of Earth in Relation to the Solar System?

  • hafiz ns
  • · Replies 5 ·
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5

Graduate Modified Newtonian Dynamics vs. Quantum Gravity

  • sderamus
  • · Replies 1 ·
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1

Humans Settling on the Moon: What Do You Think?

  • @PK nd
  • · Replies 78 ·
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78

Undergrad Can Neutrinos Escape Black Holes?

  • Stephanus
  • · Replies 18 ·
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18

Graduate Does space have a velocity in spacetime?

  • eaglechief
  • · Replies 5 ·
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5

Graduate Finding Number of Stars that have Died

  • astrofunk21
  • · Replies 3 ·
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3

Undergrad Why don't black holes become stars again?

  • azhelton69
  • · Replies 12 ·
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12

Graduate How do you project a Sersic Profile into 3D?

  • Earnest Guest
  • · Replies 1 ·
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1

Graduate Accurate measurement of z = 8.68 galaxy

  • marcus
  • · Replies 16 ·
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16

Graduate Can We Measure the Probability of Order in the Universe?

  • Morphsnorkle
  • · Replies 8 ·
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8

Graduate The Lords of the Rings among centaurs

  • PF_SpaceNews
  • · Replies 3 ·
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3

Graduate How/Why does GR break down in Planck Epoch?

  • Buzz Bloom
  • · Replies 8 ·
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8

Undergrad Size of the Universe: Imperial & Metric Measurements

  • samisbored
  • · Replies 17 ·
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17

Graduate Size of Universe: Planck Time to Inflation

  • clinden
  • · Replies 7 ·
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7

Stargazing Got my First Telescope | Celestron Sky Prodigy 130 | Astrophotography

  • Glenstr
  • · Replies 32 ·
2
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32

High School Who discovered the cause of a red moon?

  • Opus_723
  • · Replies 3 ·
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3

High School Unraveling the Mystery of the Comet Dust Layer

  • fred20
  • · Replies 5 ·
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5

Undergrad How much does weight affect re-entry into the atmosphere?

  • stacks
  • · Replies 1 ·
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1

Graduate Could the Higgs Boson Help Identify Dark Matter?

  • Quds Akbar
  • · Replies 5 ·
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5

High School Mars panorama from Curiosity shows petrified sand dunes

  • PF_SpaceNews
  • · Replies 1 ·
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1

Graduate How much is popping into and out of

  • udtsith
  • · Replies 2 ·
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2

Undergrad How do we determine distances of objects in space?

  • AaromTheBritt
  • · Replies 1 ·
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1

Russian cosmonaut back after record 879 days in space

  • PF_SpaceNews
  • · Replies 4 ·
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4

Graduate Questions re electroweak de-unification during inflation

  • Buzz Bloom
  • · Replies 2 ·
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2

Graduate How can I apply probability to the cosmological constant?

  • Shadowclan
  • · Replies 2 ·
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2

Undergrad Why Does Earth Appear Mostly Blue from Space?

  • rootone
  • · Replies 3 ·
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3

Graduate Understanding Big Bang Singularity: Physics Forums Q&A

  • Buzz Bloom
  • · Replies 26 ·
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26

High School A Question About Parallel Universes....

  • BadgerBadger92
  • · Replies 2 ·
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2

High School Why does Pluto revolve clockwise

  • Saleh0003
  • · Replies 5 ·
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5

Is Galileo Similar to GPS?

  • PF_SpaceNews
  • · Replies 2 ·
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2

Sweeping over the south pole of Mars

  • PF_SpaceNews
  • · Replies 1 ·
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1

Undergrad Planet at the center of mass of a binary star system

  • John Fluharty
  • · Replies 4 ·
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4

High School Could we throw stuff into space?

  • kieyard
  • · Replies 14 ·
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14

Undergrad Moon's crust as fractured as can be

  • PF_SpaceNews
  • · Replies 7 ·
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7

Graduate VSl theoreis and energy creation

  • palmer eldtrich
  • · Replies 1 ·
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1

Undergrad Stochastic Matrices in Cosmology

  • TRB8985
  • · Replies 5 ·
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5

Undergrad Astronomers find galaxy cluster with bursting heart

  • PF_SpaceNews
  • · Replies 3 ·
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3

Graduate Underground magma ocean could explain Io's 'misplaced' volcanoes

  • PF_SpaceNews
  • · Replies 1 ·
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1

SETI reborn—the new search for intelligent life

  • PF_SpaceNews
  • · Replies 2 ·
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2

The Mysteries of Cosmic Ray Data: A Comprehensive Guide

  • Tone L
  • · Replies 3 ·
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3

Graduate Does Redshift Change Over Time for a Constant Recession Speed?

  • JohnnyGui
  • · Replies 11 ·
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11

Undergrad Who first found the Heliocentric or Geocentric Distances

  • Philosophaie
  • · Replies 8 ·
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8

Graduate Cassini confirms global ocean at Enceladus

  • mfb
  • · Replies 4 ·
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4

Graduate Neutral hydrogen gas in galaxy clusters

  • PF_SpaceNews
  • · Replies 2 ·
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2

Graduate Finding the One Degree Peak in a Power Spectrum

  • gluon
  • · Replies 15 ·
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15

Graduate Oxygen is not definitive evidence of life on habitable extrasolar planets

  • PF_SpaceNews
  • · Replies 4 ·
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4

Graduate How Do You Calculate Hydrogen Ionization Using a Metagalactic Radiation Field?

  • astrofunk21
  • · Replies 2 ·
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2

Graduate How Can I Derive the Kepler Equation?

  • Philosophaie
  • · Replies 4 ·
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4

Graduate Convert from Magnitude Density to Mass

  • Earnest Guest
  • · Replies 1 ·
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1
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8

Graduate Astronomers discover how lowly dwarf galaxy becomes star-forming powerhouse

  • PF_SpaceNews
  • · Replies 1 ·
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1

Undergrad Which is more realiable: NED or SIMBAD?

  • Earnest Guest
  • · Replies 1 ·
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1

China aims to be first to land probe on moon's far side

  • PF_SpaceNews
  • · Replies 5 ·
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5

Graduate Celeste: A new model for cataloging the universe

  • PF_SpaceNews
  • · Replies 2 ·
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2

Graduate Question about first peak of CMB

  • gluon
  • · Replies 1 ·
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1

Graduate Planck Stars & FRBs: Rovelli's Hypothesis

  • skydivephil
  • · Replies 3 ·
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3

Graduate How do I calculate the event horizon?

  • Spring
  • · Replies 3 ·
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3

Undergrad Young gas giants fly close to their suns

  • PF_SpaceNews
  • · Replies 4 ·
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4

Undergrad Is Dark Matter Present in the Milky Way Galaxy?

  • Tony Stark
  • · Replies 6 ·
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6

Undergrad The Universe accelerating and light

  • Jaami M.
  • · Replies 11 ·
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11

Graduate What are the best parameters for λCDM?

  • Earnest Guest
  • · Replies 19 ·
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19

Undergrad Could a Tidal Lock Cause the Earth to Stop Rotating?

  • tony1grendel
  • · Replies 28 ·
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28

Graduate Higgs cyclic model from Steinhardt, Turok, Bars

  • palmer eldtrich
  • · Replies 3 ·
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3

Graduate Universe Expansion: What are the Limits?

  • Tiago
  • · Replies 1 ·
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1

Graduate Time between farthest and closest distance from Jupiter

  • Nathanael
  • · Replies 1 ·
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1

Graduate Gravitational Lensing: Wave or Particle Nature?

  • Varun Lall
  • · Replies 7 ·
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7

Graduate Gravitational lensing and Dark Energy

  • astrolollo
  • · Replies 7 ·
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7

Graduate Heory of Spacetime Curvature and Gravity

  • twelfthroot2
  • · Replies 6 ·
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6

Undergrad Where Does Earth's Counter Gravity Go in an Expanding Universe?

  • Ahmed Nabi
  • · Replies 72 ·
3
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Graduate Can Neutrinos Prevent Cavities?

  • CygnusX-1
  • · Replies 2 ·
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2

Solar Tornado Captured by NASA's SDO Probe

  • Mordred
  • · Replies 3 ·
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3

What can we learn about the Milky Way using an 85mm lens and static tripod?

  • Andy Resnick
  • · Replies 30 ·
2
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30

Insights A Poor Man's CMB Primer Part 0: Orientation - Comments

  • bapowell
  • · Replies 4 ·
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4

High School Is the Milky Way at the center of the expanding universe?

  • Passionate Eng
  • · Replies 7 ·
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7

Graduate The Age Distribution of Intelligent Life in the Milky Way

  • Chronos
  • · Replies 5 ·
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5

High School Unveiling the Mystery of our Spiral Galaxy

  • Passionate Eng
  • · Replies 2 ·
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2

Graduate Questions About Contact in the Movie

  • skredp
  • · Replies 28 ·
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28

Graduate WMAP Q&A: Information about Powerspectrum & Inflation

  • gluon
  • · Replies 7 ·
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7

Graduate What defines the surface of the Sun?

  • Hornbein
  • · Replies 2 ·
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2

Undergrad Data for Earth Orbiting Satellite & Ionosphere: Research Help

  • Tone L
  • · Replies 1 ·
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1

Graduate Light in the expanding space universe

  • Gerinski
  • · Replies 13 ·
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13

Graduate Does Zero Net Energy equal Zero Energy?

  • Athanatsius
  • · Replies 10 ·
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10

Graduate Exact Classical Correspondence in Quantum Cosmology?

  • Garth
  • · Replies 6 ·
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6

Graduate How Has General Relativity Evolved Over 100 Years?

  • Garth
  • · Replies 3 ·
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3
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30

Graduate The Inflationary and The Big Bang Theory

  • yazanhomsi
  • · Replies 2 ·
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2

High School Presenting to middle-schoolers on black holes - suggestions?

  • Ghostcrown
  • · Replies 4 ·
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4

Graduate Age of Universe in Planck normalized units

  • Filipe Salles
  • · Replies 2 ·
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2

Undergrad A question about the flatness of galaxies

  • JohnnyGui
  • · Replies 17 ·
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17

Graduate How can we calculate universe diameter at a given time

  • Quarlep
  • · Replies 40 ·
2
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40