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 Why is it called the 'Universe?'

  • EndlessTime
  • · Replies 9 ·
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9

Graduate Will charged black holes evaporate?

  • Tachyonguy
  • · Replies 23 ·
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23

Undergrad Hubble Constant am I gettting this right?

  • Loki180
  • · Replies 25 ·
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25

High School Why do black holes have such strong gravitational pull?

  • Mabcs
  • · Replies 3 ·
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3

Graduate Orbital period of a star in the Milky Way?

  • jcott
  • · Replies 9 ·
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9

Graduate Why Don't Observations Support the Big Bang's Optical Predictions?

  • h_cat
  • · Replies 10 ·
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10

Stargazing Pictures from the Hubble Space Telescope

  • Naty1
  • · Replies 2 ·
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2

Graduate Bigbang and the begginnig of time

  • adjacent
  • · Replies 5 ·
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5

High School Why Isn’t the Night Sky Full of Light from All the Galaxies?

  • adjacent
  • · Replies 8 ·
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8

Undergrad Satellite with period equal to that of its planet?

  • Humaj
  • · Replies 3 ·
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3

Need a good analogy of finding life in the universe

  • uperkurk
  • · Replies 36 ·
2
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36

Common miscons (e.g. it exploded from a singularity) &why to check FAQ

  • marcus
  • · Replies 14 ·
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14

Undergrad Looking for some help understanding the Big Bang.

  • Outasight
  • · Replies 1 ·
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1

Graduate What's the bandwidth of the Cosmic Microwave Background radiation?

  • SpaceBear
  • · Replies 14 ·
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14

Graduate How Universe is expanding faster than speed of light?

  • SecretOfnumber
  • · Replies 4 ·
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4

High School Space and Matter: Does it Push Objects?

  • adjacent
  • · Replies 2 ·
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2

Undergrad Kepler mission announces possibly habitable planets found (18 April)

  • marcus
  • · Replies 6 ·
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6

Graduate World's record for highest freq photon ever seen, nature or lab?

  • Albertgauss
  • · Replies 4 ·
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4

Graduate CMB Angular Distribution: Understanding Gaussian Random Fields

  • Madster
  • · Replies 3 ·
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3

Graduate NASA working on warp drive experiments

  • PhysicsDad
  • · Replies 3 ·
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3

Undergrad What Defines a Different Universe?

  • PhyHunter
  • · Replies 5 ·
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5

Graduate Did inflation set off the universe?

  • SaxophoneofTim
  • · Replies 19 ·
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19

Graduate Video talk on Planck results by Kendrick Smith

  • marcus
  • · Replies 2 ·
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2

Graduate Black Hole Singularity of a Universe

  • tkopunek
  • · Replies 2 ·
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2

Undergrad How can the big bang allow infinate universes

  • yup790
  • · Replies 2 ·
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2

Undergrad Is the Universe Infinite or Does It Have a Center?

  • medgalis
  • · Replies 2 ·
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2

Graduate Black hole acceleration beyond C?

  • DARKRIDEE
  • · Replies 13 ·
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13

Graduate Observational Cosmology & LCDM Model: What We Know

  • Chronos
  • · Replies 1 ·
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1

Graduate Why dark matter is dark but not atoms

  • 7555
  • · Replies 5 ·
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5

Graduate Searching for Dark Energy, Dark Matter & Gravitational Radiation

  • wolram
  • · Replies 4 ·
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4

Graduate Our ideas on v_rec/c column added to J's calculator

  • marcus
  • · Replies 31 ·
2
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31

Undergrad Will PhoneSat revolutionize satellite technology?

  • Greg Bernhardt
  • · Replies 1 ·
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1

Undergrad Does three Dimension realy exsist and why?

  • SecretOfnumber
  • · Replies 2 ·
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2

Undergrad Equation of Gravity's influence relative to objects

  • Galric
  • · Replies 1 ·
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1

Undergrad What Are Quasars & How Do They Work?

  • medgalis
  • · Replies 5 ·
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5

High School Why do stars collapse in on itself ?

  • PhyHunter
  • · Replies 20 ·
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20

Undergrad How Does Spinning a Ship in Space Create Artificial Gravity?

  • Over My Head
  • · Replies 11 ·
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11

Undergrad Tidal bulge on the moon, and its facing etc

  • Curious45
  • · Replies 8 ·
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8

Graduate Report on expansion history of universe

  • wolram
  • · Replies 3 ·
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3

Graduate Hubbles law and expansion of the universe

  • trot
  • · Replies 8 ·
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8

Undergrad Origin of the Moon and it's Retreat

  • enceladus_
  • · Replies 5 ·
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5

High School Is it possible for a star to gain mass throughout it's life?

  • liubare
  • · Replies 6 ·
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6

Is Dark Matter Finally Revealing Its Secrets?

  • Tanelorn
  • · Replies 1 ·
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1

Undergrad Why is Far-UV spectrum unobservable

  • PianoDentist
  • · Replies 2 ·
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2

Undergrad Directing dangerous objects to Sun

  • Yuri B.
  • · Replies 6 ·
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6

Stargazing $1.3 billion Thirty Meter Telescope (TMT) gets approved

  • Greg Bernhardt
  • · Replies 2 ·
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2

Undergrad How exactly does the universe expand?

  • Thomas1989
  • · Replies 16 ·
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16

Undergrad Can Asteroid Mining Technology Serve as a Global Defense System?

  • thorium1010
  • · Replies 65 ·
3
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Graduate Stress Energy Tensor - Confusion about signs and metrics

  • Allday
  • · Replies 2 ·
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2

Graduate What Was the Initial Energy of the Universe: Planck Energy or Singularity?

  • liometopum
  • · Replies 3 ·
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3

Graduate How quickly would Mars loose its atmosphere?

  • Menninger
  • · Replies 3 ·
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3

High School Calculating the Kinetic Energy of a Meteor: What Factors Influence its Velocity?

  • Numeriprimi
  • · Replies 5 ·
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5

Graduate Could Dark Energy be concentrated inside galactic bubbles?

  • skeleton
  • · Replies 5 ·
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5

Graduate Why do stars collapse in ot itself? Part 2

  • PhyHunter
  • · Replies 14 ·
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14

Undergrad Observing stuff in space over various distances

  • wendal
  • · Replies 9 ·
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9

Undergrad Is Staring at a Red Dwarf Harmful?

  • AndromedaRXJ
  • · Replies 11 ·
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11

Graduate Cosmological Observations Conundrum

  • wstrohm
  • · Replies 43 ·
2
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43

Graduate Understanding Mercury's Precession

  • OnceKnown
  • · Replies 5 ·
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5

Undergrad Characteristics of electromagnetic waves traveling through the cosmos.

  • morningstar
  • · Replies 9 ·
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9

High School What is the Speed of Earth on its Orbit During Equinoxes and Solstices?

  • Yuri B.
  • · Replies 9 ·
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9

Graduate Exploring the Transparency of Black Holes: A Relativity Question

  • stargazer3
  • · Replies 17 ·
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17

Graduate Is Big Bang a Misleading Term for Describing the Early Universe?

  • dpooga
  • · Replies 1 ·
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1

Graduate Is the Solar system expanding with the Universe?

  • johne1618
  • · Replies 7 ·
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7

Graduate Are black holes explained by complex analysis?

  • Hercuflea
  • · Replies 16 ·
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16

Graduate Atomic Hydrogen gas cloud to Star

  • Brown Arrow
  • · Replies 9 ·
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9

Undergrad The acceleration of the expansion of the known universe

  • Over My Head
  • · Replies 27 ·
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27

Graduate Do All Stars Rely on Quantum Tunneling for Fusion?

  • deadscientist
  • · Replies 2 ·
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2

Graduate Why do the smallest luminous objects lie along a line corresponding to

  • Brown Arrow
  • · Replies 5 ·
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5

Graduate Eternity's Big Bounce: What Do You Think?

  • Dionysos25
  • · Replies 1 ·
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1

High School The Earth as pendulum tied not to the Sun

  • Yuri B.
  • · Replies 9 ·
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9

Undergrad Size of VY Canismajoris and gravity

  • SecretOfnumber
  • · Replies 5 ·
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5

Graduate The awkward expression 1 km/s per Mpc-the radius is better

  • marcus
  • · Replies 12 ·
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12

What is the estimated worth of a planet made entirely of diamond?

  • 42Physics
  • · Replies 21 ·
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21

Graduate Can Extended Theories of Gravity Explain Dark Matter and Dark Energy?

  • CWatters
  • · Replies 24 ·
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24

Graduate Placing a cargo on a parabolic orbit from europa moon of Jupiter

  • Cerdocyon
  • · Replies 3 ·
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3

Is the Universe Organized or Chaotic in its Younger Years?

  • capcom1983
  • · Replies 11 ·
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11

High School What is this galaxy? I can't work it out

  • Shutupwesley
  • · Replies 17 ·
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17

Graduate Shape of Universe: Is Flatness Approved? Causes of Big Crunch

  • Chemist@
  • · Replies 119 ·
4
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119

Undergrad Is there a place in the Universe without any matter and energy?

  • gen6
  • · Replies 12 ·
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12

Graduate Understanding Circumstellar Disks: Exploring Surface Density in 3D

  • robotopia
  • · Replies 6 ·
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6

High School Is Earth Orbiting the Sun Dynamically?

  • syrf3763
  • · Replies 8 ·
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8

High School Why Does the Sun Bob Up and Down in its Orbit?

  • enceladus_
  • · Replies 28 ·
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28

Graduate Can Energy exist with the absence of matter?

  • Ayham
  • · Replies 2 ·
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2

Graduate It's a rate (not a constant) so let's call it that

  • marcus
  • · Replies 8 ·
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8

Graduate Conceptual Q: Gravity, Angular Momentum, and Galaxies

  • tolove
  • · Replies 9 ·
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9

High School Is Constant Rest Possible in Outer Space?

  • MathematicalPhysicist
  • · Replies 2 ·
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2

Graduate Could the Big Bang Have Been a Massive Black Hole Eruption?

  • Randomtask94
  • · Replies 17 ·
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17

Graduate Black hole growth and evaporation

  • egcavalcanti
  • · Replies 2 ·
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2

Graduate Are Statistical Mechanics Adequate for Interstellar and Intergalactic Clouds?

  • anorlunda
  • · Replies 3 ·
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3

Graduate Nature of spacetime and interest in the field

  • Macrobe
  • · Replies 1 ·
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1

Graduate What's the latest update on the possible discovery of dark matter?

  • DiracPool
  • · Replies 13 ·
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13

Graduate What is the relationship between light and space?

  • Seminole Boy
  • · Replies 7 ·
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7

Graduate Which Planck numbers to use? (Ned Wright's choice?)

  • marcus
  • · Replies 10 ·
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10

Graduate Kudo list of well-written exchanges for the month of April :-D

  • marcus
  • · Replies 0 ·
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0

Graduate Thoughts/Questions about GR and dark matter

  • DLH112
  • · Replies 3 ·
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3

Graduate Would Dark Energy Alter Layzer's Entropy Model?

  • j1mcross
  • · Replies 8 ·
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8

Graduate Why doesn't dark matter clump together?

  • mrspeedybob
  • · Replies 1 ·
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1

High School Why Do We Search for Exoplanets?

  • wolram
  • · Replies 20 ·
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20

Graduate Formula for the dark energy density (dark energy formula)

  • Alexroma
  • · Replies 5 ·
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5

Graduate Analyse Simulated Galaxies with SDSS Telescope | Survey by J.W. Trayford

  • wmfw23
  • · Replies 3 ·
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3