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 there such a thing as lumens/m^3?Would you have to be measuring
- ABHoT
- · Replies 2 ·
Graduate Is 1/0 really infinity, or is it undefined?
- iRaid
- · Replies 4 ·
Graduate How is Hawking Radiation Derived Using the Heisenberg Uncertainty Principle?
- stevebd1
- · Replies 1 ·
High School Is Earth's Rotation Really Slowing Down?
- Bjarne
- · Replies 5 ·
Undergrad Finding the equilibrium bwetween two celestial bodies
- cm_student
- · Replies 2 ·
Undergrad What is a 'Gravitational Slingshot'?
- xilc
- · Replies 3 ·
What is the probability of life in Universe?
- Viva-Diva
- · Replies 72 ·
Graduate Why do cosmologists consider the cosmos infinite?
- shunyadragon
- · Replies 34 ·
Graduate How uniform is the expansion of the universe?
- Notvacka
- · Replies 4 ·
So what to do with knowledge of how the universe works?
- blank.black
- · Replies 5 ·
Graduate Why is Solar Cycle 24 Starting So Slowly?
- Astronuc
- · Replies 3 ·
Graduate Does vacuum energy increase during cosmic expansion?
- TrickyDicky
- · Replies 9 ·
Graduate Is the Universe's Age Finite or Infinite Beyond Our Horizon?
- Halzo82@gmail
- · Replies 7 ·
Graduate Besides the bigbang, are there other published theories about cosmic microwave
- land_of_ice
- · Replies 11 ·
Undergrad What caused the big bang and started the expansion?
- brother time
- · Replies 7 ·
Undergrad How does the three-body system (Earth, moon, Sun) work?
- spare ohs
- · Replies 1 ·
Graduate Latest on black hole infromation paradox?
- nrqed
- · Replies 9 ·
High School Are the planets where we belive these to be
- Bjarne
- · Replies 14 ·
Inner and Outer Spacewhere does it begin, your opinion.
- waterwalker10
- · Replies 4 ·
Graduate LCROSS/LRO and Their Effect on the Moon
- HeLiXe
- · Replies 7 ·
High School Why is the Moon drifting away from Earth?
- Mahbod|Druid
- · Replies 22 ·
High School Is Meade LX200 10 a Good Deal for Your CCD Scope?
- Chronos
- · Replies 5 ·
Graduate How much energy do the neutrinos passing through us carry?
- Borg
- · Replies 10 ·
High School How much has Earth's day length changed over time?
- cap7
- · Replies 1 ·
Undergrad Gravitational Disc consequence ?
- dustydude
- · Replies 1 ·
Graduate Can a Collapsing Star Form a Wormhole?
- PaulS1950
- · Replies 3 ·
Graduate Magnatars (Hypothetical Question)
- 1Truthseeker
- · Replies 6 ·
Undergrad What Is the Longest Wavelength We Can Observe in Radio Astronomy?
- kuahji
- · Replies 1 ·
Undergrad How does inflation explain the rapid expansion of the universe?
- brother time
- · Replies 1 ·
High School Do all planets have magnetospheres?
- physicallove
- · Replies 5 ·
Graduate Could Mars be terraformed by increasing its mass with asteroid impacts?
- Beer w/Straw
- · Replies 16 ·
Graduate What Happens to Neutron Stars Without Black Holes?
- land_of_ice
- · Replies 31 ·
Graduate Black holes and redshift (2 questions)
- grichblix
- · Replies 6 ·
Why No Video Streams of Space Missions?
- luma
- · Replies 12 ·
High School Why does Mercury move much faster than Pluto?
- physicallove
- · Replies 5 ·
Graduate Study group for Carroll & Ostlie's Intro to Modern Astrophysics
- jmccann
- · Replies 1 ·
Graduate Calculating Critical Density Using FRW and Its Implications
- CaptainMarvel
- · Replies 1 ·
High School What is the Max Wavelength of CMB Radiation?
- Magma828
- · Replies 4 ·
Graduate How Does a Black Hole's Gravity Vary Despite Its Infinite Density?
- danihel
- · Replies 20 ·
Graduate How did the Hydrogen Atoms formed from Energy ?
- blueinfos
- · Replies 8 ·
Graduate Supernova from black hole formation or silent collapse
- vanesch
- · Replies 13 ·
High School THE CENTER of The Milky Way Galaxy
- toiletpaper
- · Replies 3 ·
Undergrad Anthropic Principle Interpretations
- Jonnyb42
- · Replies 16 ·
Undergrad Why Haven't We Sent a Probe Into Jupiter's Depths?
- cstoos
- · Replies 7 ·
Graduate Status of Dark Flow Phenomenon: Kashlinsky's Claim
- HossamCFD
- · Replies 2 ·
Undergrad Universe 93 billion light years?
- filegraphy
- · Replies 3 ·
Graduate Hawking On The Edge Of The Universe
- TimBowe
- · Replies 20 ·
Graduate Apparent superluminal velocity in M82 source
- jackiefrost
- · Replies 3 ·
Graduate Could this be an explanation why there is more matter than antimatter?
- Heinlein
- · Replies 16 ·
Undergrad If Mass can be turned into energy, can enegry be turned to Mass?
- Bobbie Dae
- · Replies 6 ·
Undergrad Can the Sun be treated as a black body radiator?
- Major_Disaster
- · Replies 5 ·
Graduate Size comparison of WASP-12b (gray) with Jupiter.
- Orion1
- · Replies 1 ·
Graduate Our universe is a Black Hole in a 10D universe
- WmCElliott
- · Replies 1 ·
Graduate Discontinuity of Spacetime (and other things)
- Jonnyb42
- · Replies 6 ·
Graduate Distunguishing matter/antimatter black holes
- skippy1729
- · Replies 22 ·
What is the energy of planets and how is it produced?
- mreq
- · Replies 5 ·
Graduate Black hole inside a larger black hole.
- Meatbot
- · Replies 33 ·
High School Difference between asteroids, meteorites and meteors
- Frannas
- · Replies 1 ·
Graduate Is the Universe Infinite or Finite?
- Jake4
- · Replies 68 ·
Graduate How energy divided up in early Universe.
- Spinnor
- · Replies 4 ·
Undergrad Space Weather reports possibility of Hyder Flare that will hit the earth
- Glennage
- · Replies 5 ·
Was the 1969 Moon Landing a Hoax?
- RoughRoad
- · Replies 1 ·
Graduate Are Inflation and the Multiverse Indisputably Linked?
- skydivephil
- · Replies 6 ·
Undergrad How small or large was the initial Big Bang object
- jamesadrian
- · Replies 6 ·
Graduate Does the Age of the Universe Need to Factor in Light's Expansion?
- jinny1
- · Replies 9 ·
Graduate Collapsed hypergiant forms a gamma ray pulsating black hole
- Null_
- · Replies 3 ·
Graduate Time from the origin of universe
- emc2cracker
- · Replies 5 ·
Undergrad Why do neutron stars suck the gas from their companions?
- TCS
- · Replies 10 ·
Graduate SN2005E supernova lacks carbon and oxygen, defies known mechanisms
- Nusc
- · Replies 2 ·
Undergrad Potential for Gamma Ray Bursts to Pose a Threat to Earth?
- Jonnyb42
- · Replies 1 ·
Graduate Will the Milky Way and Andromeda Collide Despite the Expanding Universe?
- buddhakan
- · Replies 2 ·
Graduate Topography of Spacetime over time
- D.S.Beyer
- · Replies 2 ·
Graduate Can a Black Hole Be Weaponized?
- Dr Chaos
- · Replies 36 ·
Re:star crust 10 billon times stronger than steel
- bayboy144l
- · Replies 11 ·
Graduate How do physicists know spacetime formed at the big bang from galaxy recession?
- Jonnyb42
- · Replies 1 ·
Graduate What do mainstream cosmologists mean by Infinte universe ?
- HossamCFD
- · Replies 18 ·
Undergrad Finding Distance to Sirius Using Parallax Method
- yukkuy
- · Replies 6 ·
High School Why does the Moon keep the same face toward Earth but Earth doesn't toward the Sun?
- Martin Rattigan
- · Replies 4 ·
High School Did the Big Bang really start the universe from nothing?
- Mr. Pullen
- · Replies 44 ·
Did aliens hijack Voyager 2?
- physixlover
- · Replies 12 ·
Graduate Age of the universe from a photons point of view
- skydivephil
- · Replies 18 ·
High School Can we reach the edge of the universe if it contracts in a big crunch?
- RikTammenaers
- · Replies 22 ·
High School Earth's Rotation Speed: Would We Notice?
- epr2008
- · Replies 5 ·
Graduate Is the Dark Matter Hypothesis Failing to Explain Galaxy Formation?
- Saul
- · Replies 46 ·
Undergrad Why Don't Stars Expand with Space?
- menniandscience
- · Replies 2 ·
Graduate Is M-theory Defined by Speculative Events?
- tohamas
- · Replies 8 ·
Graduate Is there more to the universe than what we can see?
- seto6
- · Replies 3 ·
Graduate Couple of questions about black holes and event horizons
- Varine
- · Replies 23 ·
High School How much of space has humanity observed?
- Unit
- · Replies 1 ·
Graduate WMAP evidence for cosmic neutrino background and early star formation
- SF
- · Replies 4 ·
High School Does space end or continue forever, and what does that mean for its shape?
- spaceends
- · Replies 6 ·
Graduate Can science explain what the universe expands into?
- menniandscience
- · Replies 9 ·
Undergrad Does water on Mars and the Moon expand the habitable zone?
- cstoos
- · Replies 4 ·
NY Times Article: Mater vs. Anti-Mater
- diogenesNY
- · Replies 1 ·
Undergrad Is Dark Matter a Cop-Out in Cosmology?
- chuchulainn
- · Replies 3 ·
Graduate Quark Degeneracy? String Degeneracy? (and the effect on Black Holes)
- mjacobsca
- · Replies 2 ·
Undergrad Simple description of a Singularity
- tit4tat
- · Replies 12 ·
Undergrad Why didn't gravity collapse the early universe after the Big Bang?
- Bolo1
- · Replies 24 ·
Graduate Why do we need inflation to explain the homogeneity of CMB?
- petergreat
- · Replies 6 ·
Graduate Explosion/expansion isn't there a period of acceleration
- awestruck
- · Replies 10 ·