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

Stargazing Solar and Lunar Eclipse - size of moon

  • samona
  • · Replies 2 ·
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2

Undergrad Was There Matter or Energy at the Start of the Big Bang?

  • grantwilliams
  • · Replies 16 ·
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16

Graduate One of the standard candle methodologies

  • ehabmozart
  • · Replies 3 ·
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3

Graduate Do Neutron Stars Eventually Decay Into Black Holes?

  • iced199
  • · Replies 7 ·
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7

Undergrad Why Are Red Giants More Luminous Than Other Stars?

  • ehabmozart
  • · Replies 4 ·
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4

Graduate Neutron escaping to parallel universe

  • billa12
  • · Replies 1 ·
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1

Graduate The Shape of the Universe: What is a Flat Universe?

  • TonyTT
  • · Replies 10 ·
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10

Graduate What Physics Laws Govern the Rotation of Astronomical Structures?

  • Paulibus
  • · Replies 4 ·
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4

Undergrad Are All Stars the Same Size Due to Nuclear Fusion?

  • TonyTT
  • · Replies 6 ·
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6

High School Need Research Question Related to Multiverse (High School Level)

  • shaz.662
  • · Replies 46 ·
2
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46

Undergrad Question about detection of very far away objects

  • SolidHelix
  • · Replies 13 ·
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13

High School What should we call other universes besides 'parallel universes'?

  • Imranfish
  • · Replies 4 ·
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4

Graduate What is the equation for high (cosmological) redshift?

  • JArnold
  • · Replies 1 ·
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1

High School Can anyone help me disprove something

  • Timenspace
  • · Replies 1 ·
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1

Undergrad Is Oxygen More Abundant Than Carbon in the Universe Due to Nuclear Fusion?

  • iced199
  • · Replies 6 ·
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6

Undergrad How to calculate g-forces on pilots in climbs, dives, outer space

  • Albertgauss
  • · Replies 3 ·
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3

Graduate Could dark energy be used as an antigravity device?

  • iced199
  • · Replies 1 ·
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1

Undergrad When does helium fusion occur in an evolution of star?

  • ehabmozart
  • · Replies 3 ·
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3

High School Objects in Space: Does Microgravity Change the Rules?

  • oumaima1
  • · Replies 3 ·
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3

Graduate Calculating Historical Positions of the Asteroid Belt's Orbit

  • jackpelham
  • · Replies 11 ·
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11

Graduate Is Hawking Radiation inherently unimportant?

  • Rorkster2
  • · Replies 2 ·
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2

Graduate Sunrise and sunset correction for astronomical and geographical factors

  • Galip
  • · Replies 8 ·
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8

Graduate Warp Drive & Bubble Theory: Can You See & Touch It?

  • Reptile202
  • · Replies 7 ·
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7

Graduate Does the Total Energy of a Black Hole Change During Evaporation?

  • DrZoidberg
  • · Replies 3 ·
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3

Graduate Is our universe the unique possible outcome of the big bang

  • avery
  • · Replies 11 ·
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11

Graduate Is the speed of light the limit of our universe?

  • bedsheet010
  • · Replies 21 ·
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21

Stargazing Using a Telescope: 30X Power for Planets & Moons

  • m~ray
  • · Replies 8 ·
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8

Graduate Black Holes: Infalling Observers and BH Evaporation

  • Drakkith
  • · Replies 37 ·
2
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37

Graduate Size of fictional planet based on gravity and density

  • rdanner3
  • · Replies 3 ·
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3

Graduate 'Density' of 2.73K Cosmic Microwave Background

  • tasp77
  • · Replies 3 ·
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3

High School What happens to the missing time?

  • amalmirando
  • · Replies 1 ·
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1

Graduate Redshift and Expansion of the Universe

  • MattRob
  • · Replies 27 ·
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27

Satellite Purchase: Critical Help required

  • CognitiveNet
  • · Replies 2 ·
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2

Graduate Can there be a place in space where no gravity exists?

  • kamermans
  • · Replies 6 ·
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6

Undergrad Shape of Universe: Why Is It Not Spherical?

  • TonyTT
  • · Replies 16 ·
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16

Graduate Why isn't the universe a big black hole?

  • ncarron
  • · Replies 21 ·
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21

Graduate From Boomerang to Planck: reading the ancient light

  • marcus
  • · Replies 8 ·
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8

Stargazing What creates the star points in telescope pictures of stars?

  • rbj
  • · Replies 24 ·
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24

Graduate The universe total energy and the conservation of energy

  • Gjovik10
  • · Replies 2 ·
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2

Graduate Questions about Parallel Worlds by Michio Kaku: the big bang

  • ail
  • · Replies 2 ·
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2

Graduate Calculating Pluto's Orbital Time Above/Below Ecliptic

  • Globe199
  • · Replies 1 ·
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1

Graduate Could the Visible Universe Be a Fuzzball in String Theory?

  • Jonny_trigonometry
  • · Replies 2 ·
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2

Graduate Question about white/black holes

  • EvanD
  • · Replies 16 ·
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16

Undergrad Why Do We See So Many Gamma Ray Bursts?

  • SHISHKABOB
  • · Replies 8 ·
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8

High School Is This a Solar Flare?" - Investigating Possible Phenomenon

  • Neptulin
  • · Replies 2 ·
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2

Undergrad How delicate is the Earth's Orbit?

  • esmeralda4
  • · Replies 2 ·
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2

Graduate Multiple collections of energy, very far apart

  • coktail
  • · Replies 4 ·
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4

Graduate Calculating Tithis in the Hindu Calendar - Petrix108's Query

  • petrix108
  • · Replies 2 ·
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2

Undergrad Classification of stars by spectrum

  • ehabmozart
  • · Replies 1 ·
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1

Undergrad Measuring Radial Velocity with Amateur Equipment

  • Drakkith
  • · Replies 1 ·
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1

High School The dereference between; astrophysics, astronomy, cosmology and space science

  • wolfspirit
  • · Replies 2 ·
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2

Graduate Can Different Vacuum States in Curved Spacetime Appear Thermal to Each Other?

  • grammophon
  • · Replies 3 ·
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3

High School Gravity between the Earth and the Moon

  • mynameistessa
  • · Replies 3 ·
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3

Venus passes in front of our sun

  • Naty1
  • · Replies 9 ·
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9

Undergrad How are panatery Nebula formed and when do they die

  • ehabmozart
  • · Replies 1 ·
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1

Graduate How to Compute the Length of a Year on Earth in a Two-Body System?

  • nikolafmf
  • · Replies 6 ·
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6

Undergrad The stellar evolution. Low Mass stars

  • ehabmozart
  • · Replies 5 ·
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5

Graduate Accretion disk/black hole/gas jets

  • bassplayer142
  • · Replies 21 ·
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21

Undergrad Why Do We Use Angular Size Instead of Steradian for Objects in the Night Sky?

  • 4everphysics
  • · Replies 1 ·
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1

Graduate Is anything falling into a black hole *now*?

  • ith
  • · Replies 7 ·
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7

Graduate VLBI SETI: Detecting Signals in Gliese 581 System

  • Chronos
  • · Replies 6 ·
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6

Undergrad Spectrum of Stars: Explaining the Spectral Lines of Stars

  • ehabmozart
  • · Replies 2 ·
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2

Undergrad What causes the pressure in a neutron star?

  • lntz
  • · Replies 15 ·
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15

Undergrad Width of Spectral Lines: Explaining Main Sequence Star Determination

  • ehabmozart
  • · Replies 1 ·
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1

Undergrad So much of diversity in universe.

  • rishi.sharma
  • · Replies 5 ·
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5

Graduate What Causes the Beamed Emission of Pulsars?

  • RHK
  • · Replies 11 ·
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11

Graduate How do accretion disks and black holes interact with electromagnetic forces?

  • Holesarecool
  • · Replies 9 ·
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9

Graduate Understanding the Scale Factor in the Friedman Equation | Cosmology Explained

  • robertjford80
  • · Replies 14 ·
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14

Graduate How Do Low Mass Stars Evolve After Exhausting Hydrogen Fuel?

  • ehabmozart
  • · Replies 1 ·
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1

Graduate Messenger particles and black holes

  • Warp
  • · Replies 10 ·
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10

Undergrad Definition of a Planet (and other stuff)

  • paldin
  • · Replies 6 ·
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6

High School Question about momentum in vacuum of space

  • kris_yo
  • · Replies 2 ·
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2

Graduate Understanding the Density Parameter in Cosmology: Matts Roos' Text Explanation

  • robertjford80
  • · Replies 9 ·
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9

High School Astronomical-objects outside our own galaxy

  • johann1301
  • · Replies 5 ·
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5

Graduate What Happens If We Travel in One Direction in the Universe?

  • robertjford80
  • · Replies 11 ·
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11

Graduate Higgs Field, Big Bang, and Spacetime

  • coktail
  • · Replies 7 ·
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7

Graduate Patched Conics Trajectory from Initial Orbit State

  • TheHarvesteR
  • · Replies 9 ·
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9

Graduate How Does an Infinite Static Arrangement Collapse Under Gravity?

  • Rear Naked
  • · Replies 8 ·
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8

Graduate Universe structure, movement, creation/destruction

  • Eurakhunt
  • · Replies 1 ·
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1

Graduate Could a new type of compass be created using a rotating permanent magnet?

  • Robin07
  • · Replies 1 ·
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1

Graduate The WMAP objective is to measure the temperature differences in the

  • azizlwl
  • · Replies 1 ·
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1

Graduate The big bang model, time, and general relativity

  • Hypatio
  • · Replies 17 ·
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17

What is the scale of our universe?

  • goldsax
  • · Replies 2 ·
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2

Graduate Asteroid orbit determination from observations

  • solarblast
  • · Replies 3 ·
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3

Graduate Are objects disappearing as the universe expands?

  • 4everphysics
  • · Replies 19 ·
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19

Graduate Cosmic Microwave Background Radiation, why from 380,000?

  • 4everphysics
  • · Replies 8 ·
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8

Undergrad Can anyone recommend any astronomy books

  • Astronomyboy
  • · Replies 1 ·
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1

Graduate Unraveling the Mystery: Superstring Theory and the Timeline Before the Big Bang

  • robertjford80
  • · Replies 12 ·
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12

Graduate Is Time an Irrational Concept in Space-Time Understanding?

  • shotgun
  • · Replies 13 ·
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13

Graduate How does frame dragging cause a stick to rotate in the opposite direction?

  • Holesarecool
  • · Replies 1 ·
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1

Graduate More exact prediction of collision with Andromeda galaxy

  • marcus
  • · Replies 1 ·
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1

Graduate The flatness of the observable and unobservable univ

  • robertjford80
  • · Replies 24 ·
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24

Undergrad Transiting Exoplanet Light Curve

  • Drakkith
  • · Replies 10 ·
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10

Graduate Can alternate radiation model explain redshift?

  • shotgun
  • · Replies 15 ·
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15

Undergrad What Does a Redshift Calculation of 2.5 Mean?

  • eggman100
  • · Replies 8 ·
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8

Graduate What are the jets from a feeding blackhole made of?

  • Lino
  • · Replies 4 ·
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4

Undergrad Length of the life of a red supergiant.

  • crawleen
  • · Replies 4 ·
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4

Undergrad The Mystery of the Universe's Fate

  • azizlwl
  • · Replies 12 ·
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12

Undergrad Does 4th Dimension Space Really Exist Beyond Our Perception?

  • jd12345
  • · Replies 7 ·
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7

High School Do objects within a galaxy rotate in the same direction as the galxy itself?

  • Lino
  • · Replies 5 ·
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5