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
Graduate Does the empty Milne Universe have a horizon problem?
- johne1618
- · Replies 23 ·
How do you pronounce perilune and apolune
- flyingpig
- · Replies 1 ·
Graduate Dark matter: gamma rays, direct detection, and solar-system tests
- bcrowell
- · Replies 1 ·
Graduate What Explains the Abundance of Matter During the Annihilation Phase?
- Cosmo Novice
- · Replies 1 ·
Graduate Yesterday's Nuclear Decay Related to Today's Flare
- Dotini
- · Replies 8 ·
Undergrad Viewing the beginning of the universe.
- simbiote3
- · Replies 7 ·
Graduate Critical density formula hides fundamental relationship?
- johne1618
- · Replies 4 ·
Graduate Is Our Universe Really Flat or is it Just Euclidean Jargon?
- mtv22
- · Replies 2 ·
Graduate 10 ^18 Amps, Universal Record for Current
- Dotini
- · Replies 3 ·
Graduate Black Hole White Hole in $\Lambda$CDM Cosmology
- wolram
- · Replies 1 ·
Graduate Extremely Advanced Materials from Manipulation of Space-time
- Shaira
- · Replies 18 ·
Graduate Presuppositions of Standard Model?
- skippy1729
- · Replies 4 ·
Stargazing What telescope aperture is needed for spectroscopy of star clusters within MC?
- randa177
- · Replies 10 ·
Graduate Could a Pre-Big Bang Civilization Have Existed?
- Kalantir
- · Replies 6 ·
Undergrad Question about the Moons formation.
- YoungDreamer
- · Replies 1 ·
Graduate Does the CMBR have a detectable absorption spectrum?
- JDoolin
- · Replies 8 ·
Graduate Is General Relativity Wrong on Large Scales?
- Dotini
- · Replies 4 ·
Undergrad Can we explore white dwarfs with robotic missions?
- bostonnew
- · Replies 12 ·
Undergrad What is the case against the theory of cosmic evolution?
- bostonnew
- · Replies 25 ·
Graduate Question about the expansion of the universe/inflation
- TheIsh
- · Replies 2 ·
Graduate Could the Shape of the Universe be Explained by Black Holes and Supernovas?
- IanBeatbox
- · Replies 3 ·
Graduate Black holes in the early universe
- bcrowell
- · Replies 1 ·
Graduate Star gets torn apart by massive black hole
- AntonL
- · Replies 4 ·
Graduate Big Bang Mystery: Where Did the Explosion Take Place?
- QAZI
- · Replies 15 ·
Graduate What is retrograde planetary perihelion precession?
- magheera
- · Replies 2 ·
High School How Do You Locate Saturn and Jupiter with a Medium Powered Telescope?
- tmoan
- · Replies 3 ·
Astronomy & 2012: What Does It Mean?
- esmeralda4
- · Replies 8 ·
Graduate Inflation, Mach's Principle & the Early Universe
- Bob3141592
- · Replies 7 ·
Graduate What Role Did Electrons and Positrons Play in the Early Universe?
- narrator
- · Replies 4 ·
Graduate Heat Death vs. Bounce: Which Is the True Fate of the Universe?
- wolram
- · Replies 9 ·
Undergrad Big Bang Expansion: Faster than Light?
- Cbray
- · Replies 2 ·
Graduate How does the Earth-Moon system gain energy despite tidal interactions?
- AntonL
- · Replies 8 ·
Stargazing Solar Eclipse - Are we just lucky?
- cramdogs
- · Replies 11 ·
High School Theory of the Universe - 14-Year-Old's Perspective
- Cbray
- · Replies 2 ·
Graduate Black Hole - Questions (discussion)
- Interested In
- · Replies 7 ·
Graduate Speed of light: making non-Newtonian physics tangible
- dotancohen
- · Replies 10 ·
Graduate Accelerating Universe Expansion’s Implications? (layman’s questions)
- shawn-m
- · Replies 6 ·
Graduate Is the Heat Death of the Universe Inevitable and What Can We Do About It?
- Delong
- · Replies 35 ·
Graduate Plot of energy against space-time
- axiomatical
- · Replies 4 ·
High School How would I measure the angle of a certain street from true north?
- Ironside
- · Replies 9 ·
Graduate What is there actually to say of wormholes at the moment?
- TubbaBlubba
- · Replies 11 ·
Model of the universe/s, multiverse's etc (just a thought nothing more )
- great_sushi
- · Replies 3 ·
Undergrad Star Swallowed by Galactic Black Hole
- RJ Emery
- · Replies 4 ·
Graduate Will the Expanding Universe Eventually Become Invisible?
- Whateverworks
- · Replies 3 ·
High School View Saturn Through a Telescope: A Noob's Guide
- Eats Dirt
- · Replies 5 ·
Graduate Unraveling the Mystery of STEP Mission: What Happened and What's Next?
- jumpjack
- · Replies 1 ·
Graduate Positions on possible parallel universe theory
- R=2GM/c^2
- · Replies 1 ·
Graduate Evolution of Elementary particles?
- Aztral
- · Replies 2 ·
Graduate Does the speed of light change if?
- lawnmower man
- · Replies 17 ·
Graduate Would a Neutron Star Stop a Neutrino?
- Islam Hassan
- · Replies 20 ·
Graduate Why are Andromeda and the Milky Way approaching each other?
- Endervhar
- · Replies 16 ·
Undergrad How are Cepheids used to measure distances?
- Mooky
- · Replies 5 ·
Undergrad Can we identify the generation of any star?
- bostonnew
- · Replies 1 ·
High School View Saturn w/ 1100x120 Reflector: Eye Piece Guide
- cas888
- · Replies 1 ·
Graduate Is the Sun Going Through a Period of Weakening?
- Dotini
- · Replies 2 ·
Undergrad How Do We Calculate the Gravity of Different Particles and Celestial Bodies?
- mvan4310
- · Replies 5 ·
Graduate Neutron Star to Black Hole Via OMG?
- Islam Hassan
- · Replies 8 ·
Undergrad Stefans Boltzmann Law: Find Star Luminosity
- shugar37
- · Replies 2 ·
Graduate Young star generations: where do they get their Hydrogen?
- ExNihilo
- · Replies 10 ·
Graduate Rate and direction of expansion of the universe
- asimov42
- · Replies 6 ·
Exciting Physics Projects: Get Help Choosing Your Next Project!
- usha
- · Replies 3 ·
Undergrad Temperature - Effect on atmospheric pressure.
- ExcessRed
- · Replies 13 ·
Graduate What is the evidence on Big Bang versus steady state cosmologies?
- Greg Bernhardt
- · Replies 1 ·
Graduate What is CMB Rest? - Explained by Forum Experts
- Greg Bernhardt
- · Replies 1 ·
Graduate Black Hole Mass Flows: Is the Balance 0%?
- Islam Hassan
- · Replies 3 ·
Undergrad What is the significance of hour angle in astronomical observations?
- randa177
- · Replies 5 ·
Graduate Gravitational perturbations = tidal forces?
- Deadstar
- · Replies 1 ·
Graduate Is the universe entirely predictable, or is it based in probability?
- Sylickon
- · Replies 10 ·
Undergrad Are Black Holes Hot? A Deeper Look
- Cbray
- · Replies 5 ·
Graduate Did Gravity Exist Before the Big Bang?
- Sylickon
- · Replies 8 ·
Undergrad Planet orbital location database
- krsbuilt
- · Replies 5 ·
Graduate Is the Universe Based on a Simple Binary Code?
- lowing99
- · Replies 2 ·
Graduate Can Black Holes be Propelled by Ion Engines?
- cph
- · Replies 5 ·
Undergrad What happens when a second mars appears?
- Sp33df0rc3
- · Replies 4 ·
High School Spectacular solar eruption 7 june 2011
- AntonL
- · Replies 8 ·
Graduate Age of Universe: Defining Time from Big Bang
- Chewz
- · Replies 1 ·
Graduate Possible non-existence of black holes and its consequences
- stephenwlin
- · Replies 9 ·
Graduate Fate of Universe: Intelligent Species Impact
- Hyperspace2
- · Replies 2 ·
Graduate What is the efficiency of the Sun, really?
- cragwolf
- · Replies 7 ·
Graduate Big Bang With No Center Fallacy?
- Islam Hassan
- · Replies 5 ·
High School Black Holes and their original star
- Johnnb
- · Replies 4 ·
Graduate New Supernova Discovery Shines Bright
- Astronuc
- · Replies 2 ·
Graduate Cosmological principle and quasar distribution
- TrickyDicky
- · Replies 36 ·
Searching for list of measurements of moon-earth distance.
- azoulay
- · Replies 20 ·
Graduate Does the Holographic Principle Suggest a Schwartzchild Radius for the Universe?
- johne1618
- · Replies 2 ·
Opinions about April SciAm article about inflation inflation by Steinhardt?
- Oldfart
- · Replies 10 ·
Graduate DARK MATTER: it was always there
- zaybu
- · Replies 4 ·
Graduate Big surprise - Magnetic foam at edge of heliosheath.
- AntonL
- · Replies 2 ·
Graduate Varying Fine Structure Constant - Any recent results?
- asimov42
- · Replies 2 ·
Graduate Interaction between dark matter and normal matter
- phinds
- · Replies 24 ·
High School Does the temperature stay the same above a certain point?
- tackyattack
- · Replies 5 ·
Graduate Where the rules change, is it sudden?
- narrator
- · Replies 20 ·
Undergrad Are there any theories that explain where matter and energy came from?
- TheJoninator
- · Replies 6 ·
Graduate Black hole growth paradox question
- Grinkle
- · Replies 21 ·
Stargazing Skywatcher Skyliner 150P Dobsonian questions
- MartinJH
- · Replies 11 ·
Graduate How Does the Solar Wind's Protective Role Affect Astronomical Observations?
- unerkennbar
- · Replies 2 ·
Graduate Can a blackhole suck in another blackhole?
- mdmaaz
- · Replies 50 ·
Graduate The bounce and many universe theories
- wolram
- · Replies 9 ·
Graduate Are There Other Universes Beyond Our Own?
- revo74
- · Replies 26 ·
Undergrad Could the acceleration of expansion (of the universe) be an optical illusion?
- pdxfetal
- · Replies 7 ·