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 Definition of unshifted spectral lines?

  • Pilutiful
  • · Replies 2 ·
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2

Undergrad What is the Time Ordered Data set for CMB polarization?

  • Buzz Bloom
  • · Replies 3 ·
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3

Undergrad Is the Force on a Particle in a Homogeneous Static Universe Always Zero?

  • Higgsono
  • · Replies 22 ·
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22

Undergrad Alexander Vilenkin spontaneous creation

  • momo666
  • · Replies 5 ·
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5

Undergrad Mercury's precession due to other planets

  • greypilgrim
  • · Replies 1 ·
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1

Undergrad The Sun's habitable zone and orbital resonaces/stability

  • PlutoXenon
  • · Replies 1 ·
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1

High School Evidence for interacting dark energy from BOSS

  • wolram
  • · Replies 2 ·
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2

Undergrad How Does the Hubble Parameter Relate to Galaxy Movement?

  • Komorebi
  • · Replies 2 ·
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2

High School Earth may owe its birth to a solar eruption

  • CygnusX-1
  • · Replies 3 ·
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3

Undergrad Humidity when T is not constant in space

  • Bankoletti
  • · Replies 3 ·
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3

Undergrad What Causes the Ring Current in Earth's Magnetosphere?

  • Kara386
  • · Replies 2 ·
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2

Graduate Hubble scale and energy density during inflation

  • spaghetti3451
  • · Replies 1 ·
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1

High School Is it possible Earth is a black hole?

  • DIGBY STILLS
  • · Replies 5 ·
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5

Undergrad Entropy and Expansion in a Simple Universe

  • Grinkle
  • · Replies 40 ·
2
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40

Undergrad What is the purpose of cosmological simulations in understanding dark matter?

  • Silviu
  • · Replies 3 ·
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3

Undergrad How Can Data Constrain the Number of e-Folds During Inflation?

  • windy miller
  • · Replies 5 ·
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5

Undergrad Does a black hole cut the fabric of spacetime as it changes

  • SD das
  • · Replies 15 ·
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15

High School Why Can't We Find the Centre of the Expanding Universe?

  • SD das
  • · Replies 2 ·
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2

High School Is Dark Matter physics low or high energy physics?

  • oquen
  • · Replies 27 ·
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27

Undergrad Sun's Magnetic Field, Global Warming

  • Arman777
  • · Replies 10 ·
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10

Graduate Gravitational waves: effect of frequency on strain

  • RyuuJin
  • · Replies 4 ·
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4

High School The Early Universe and the Laws of Physics

  • Sullivan Stockwell
  • · Replies 1 ·
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1

Should we invest in Mars Exploration

  • FritoTaco
  • · Replies 186 ·
7
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186

High School Is Space an Object Capable of Bending?

  • AishaGirl
  • · Replies 6 ·
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6

High School What is the true meaning of the Big Bang?

  • Pyrus
  • · Replies 6 ·
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6

Undergrad Are quark stars a realistic solution to the black hole singularity problem?

  • rootone
  • · Replies 6 ·
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6

Undergrad How will the universe empty out?

  • durant35
  • · Replies 10 ·
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10

Undergrad Sun elevation for ISS visibility

  • Cristiano
  • · Replies 2 ·
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2

Undergrad Testing the information loss problem

  • Chronos
  • · Replies 1 ·
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1

Undergrad How far out are the probes that were sent out

  • Zahid Hasan
  • · Replies 29 ·
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29

Undergrad Entropy Change in Time of Universe

  • Arman777
  • · Replies 2 ·
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2

High School What is the origin of the Gibbons-Hawking temperature?

  • Tim Miller
  • · Replies 14 ·
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14

High School The Earth's magnetic field and moon

  • hsdrop
  • · Replies 11 ·
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11

Graduate Is Dark Energy an Illusion? A Closer Look at Concordance Cosmology

  • phyzguy
  • · Replies 26 ·
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26

Undergrad Does the number of causal patches increase bc of expansion

  • durant35
  • · Replies 4 ·
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4

Undergrad Consequence of curvature of spacetime

  • SD das
  • · Replies 3 ·
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3

Undergrad Do particles create space over time? Is that expansion?

  • negativzero
  • · Replies 12 ·
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12

Stargazing Understanding Kidney Beaning in Wide Field Eyepieces

  • sophiecentaur
  • · Replies 7 ·
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7

Undergrad Where to find in-depth info about each star's composition?

  • Guilherme Franco
  • · Replies 1 ·
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1

Undergrad How do we know we are looking back in time in space?

  • DWT
  • · Replies 25 ·
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25

Graduate What Causes a Shift in Cosmic Ray Distribution on Earth?

  • RyuuJin
  • · Replies 6 ·
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6

Undergrad Argument that a maximum density Universe expands linearly

  • jcap
  • · Replies 9 ·
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9

High School Super-Earth Found in Habitable Zone of Nearby Red Dwarf

  • CygnusX-1
  • · Replies 12 ·
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12

Why colonize Mars and not the Moon?

  • lifeonmercury
  • · Replies 817 ·
28
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817

Undergrad Can negative pions replace electrons in atoms?

  • Ranku
  • · Replies 19 ·
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19

High School What is meant by the size of the early observable universe?

  • Grinkle
  • · Replies 12 ·
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12

Undergrad Where Would Ancient Intelligent Life Have Seen Cosmic Background Radiation?

  • newphy
  • · Replies 2 ·
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2

High School Lawrence Krauss and shortening the lifespan of the universe

  • Trollfaz
  • · Replies 13 ·
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13

High School Could Boltzmann Brains Become a Reality in the Far Future?

  • Alltimegreat1
  • · Replies 26 ·
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26

Graduate Why use Earth as a gravity assist?

  • JayFlynn
  • · Replies 8 ·
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8

High School Does Negative Mass Play a Role in Hawking Radiation?

  • Allen_Wolf
  • · Replies 1 ·
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1

High School How Does Space Expand? Understanding Universe Expansion

  • dirty dan
  • · Replies 2 ·
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2

Undergrad Plateau models of inflation after Planck

  • windy miller
  • · Replies 5 ·
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5

High School Why did Aristotle arrange the planets in this order?

  • Glenn G
  • · Replies 5 ·
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5

Undergrad Oldest galaxy to date: UDFy-38135539

  • infinitebubble
  • · Replies 23 ·
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23

High School Celestial Mechanics: Eccentricity of Orbits

  • madison bond
  • · Replies 6 ·
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6

Undergrad Will the Universe one day become smaller?

  • nico nico nii
  • · Replies 29 ·
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29

Undergrad Questions about the lifecycle of stars

  • JohnnyGui
  • · Replies 77 ·
3
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77

Graduate A cosmological expansion problem too difficult for me

  • Buzz Bloom
  • · Replies 7 ·
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7

High School Is the Expansion of the Universe Uniform?

  • hsdrop
  • · Replies 5 ·
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5

Undergrad Are White Dwarfs Stars? Understanding the Classification and Characteristics

  • Jamison Lahman
  • · Replies 33 ·
2
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33

Undergrad CERN n_TOF experiment: 'Age of the Universe'

  • infinitebubble
  • · Replies 4 ·
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4

Undergrad Observing Naked Singularities: Implications for Quantum Gravity

  • windy miller
  • · Replies 1 ·
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1

High School Do we still live in a Big Bang Singularity?

  • ivant6900
  • · Replies 14 ·
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14

Undergrad Is it possible to travel between the multiverses?

  • Director_Mouse
  • · Replies 3 ·
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3

Undergrad Using big data to identify astronomocal data bias

  • Chronos
  • · Replies 4 ·
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4

Stargazing When and where is the best time to view the 2014jo25 asteroid?

  • hsdrop
  • · Replies 6 ·
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6

High School Why doesn't dark matter reside in gas clouds?

  • wolram
  • · Replies 4 ·
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4

Undergrad Why Can We Still Observe the Cosmic Microwave Background?

  • JulienB
  • · Replies 7 ·
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7

Undergrad Curvature and the size of the Universe

  • CassiopeiaA
  • · Replies 20 ·
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20

Undergrad Is there a relationship between dark matter and anti-matter?

  • Dade Murphy
  • · Replies 6 ·
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6

Graduate Micrometeorites and Karman effect

  • Arac15
  • · Replies 1 ·
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1

Undergrad Math doesn't add up: stars + planets < particles in universe?

  • Travois
  • · Replies 9 ·
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9

Graduate Understanding Expansion of Space

  • Zachary Markham
  • · Replies 54 ·
2
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54

High School Where have we looked, or are looking, for life?

  • Jarvis323
  • · Replies 9 ·
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9

Graduate Spectral Classification Syntax for Binaries

  • Solkar
  • · Replies 7 ·
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7

High School Will eLISA have the potential to detect early universe GWs?

  • binbagsss
  • · Replies 3 ·
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3

Undergrad What causes retrograde rotation in planets and moons?

  • Avimanyu Ray
  • · Replies 8 ·
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8

Undergrad Energy-momentum tensor and Friedmann Equations

  • Diferansiyel
  • · Replies 8 ·
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8

High School Naive Calculation of the Age of the Universe

  • jeffbarrington
  • · Replies 3 ·
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3

Undergrad Big Bang timing: according to what frame of reference?

  • Sophrosyne
  • · Replies 5 ·
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5

Undergrad Is a superflare capable of changing a planets orbit?

  • Edward Barrow
  • · Replies 18 ·
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18

Undergrad Can we predict the Sun's path accurately?

  • Trainee Engineering
  • · Replies 10 ·
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10

High School An exercise related to the mass of the Milky Way, sort of.

  • TreeLover
  • · Replies 2 ·
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2

Stargazing Considerations for size of telescope survey

  • BOAS
  • · Replies 2 ·
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2

High School How can we see Background radiation

  • Addez123
  • · Replies 2 ·
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2

High School Is the Universe Truly Eternal or Just a Temporary Fluctuation?

  • mcronald
  • · Replies 3 ·
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3

Undergrad Question about a magnetic dynamo on tidally locked moons

  • Althistorybuff
  • · Replies 7 ·
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7

High School Does every elementary particle eventually decay into quarks?

  • zinq
  • · Replies 13 ·
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13

Undergrad Defending the Earth from meteors using lasers

  • Dovla
  • · Replies 44 ·
2
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44

Undergrad Zero G Health Risk: Effects & Readjusting to Earth's Gravity

  • John Morrell
  • · Replies 1 ·
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1

Undergrad New Wired article on "where's the antimatter"

  • jnorman
  • · Replies 9 ·
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9

High School Finite Universe vs. Uncertainty Principle

  • Helios
  • · Replies 15 ·
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15

Insights Q&A With Universe Today's Fraser Cain - Comments

  • Greg Bernhardt
  • · Replies 4 ·
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4

High School Does the Big Bang Expansion Include All Objects in the Universe?

  • Vivek Siddarth K
  • · Replies 3 ·
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3

High School Finding Black Holes: Possible or Not?

  • Tim Layton
  • · Replies 2 ·
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2

Undergrad Observation of photons from CMB by different observers

  • BernieM
  • · Replies 7 ·
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7

High School How do black holes attract light?

  • Nabin kalauni
  • · Replies 8 ·
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8

High School Just how Powerful is Computer Science + Astrophysics?

  • Alex Shi
  • · Replies 3 ·
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3

High School Space expanding or Time speeding up? Part 2

  • CosmologyHobbyist
  • · Replies 3 ·
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3