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 Hawking radiation prevent black hole formation?
- George Jones
- · Replies 10 ·
Graduate What Is the Expansion Limit of Our Universe?
- .ultimate
- · Replies 65 ·
High School What does wave aspect mean on telescope mirror kits?
- Saladsamurai
- · Replies 11 ·
Graduate Nice thumbnail sketch of Earth's future by John Baez
- marcus
- · Replies 10 ·
Graduate Is it theoretically possible to open a stable wormhole?
- Dr.Calpol3
- · Replies 12 ·
Undergrad Could Extraterrestrial Life Exist in Unique Environments Like Titan?
- jonegil
- · Replies 31 ·
Graduate X-ray background/peculiar velocities and the Big Bang
- xratx
- · Replies 2 ·
Graduate Physical basis for dark energy-I think Bojo found it
- marcus
- · Replies 12 ·
Undergrad Why does light not slow down when moving through air?
- madphysics
- · Replies 30 ·
Undergrad What is a catastrophic nova?
- ameriti$h
- · Replies 3 ·
Graduate Condition for inflation presented by Liddle
- Magister
- · Replies 3 ·
High School Black hole video for high school physics class
- NDHurdler
- · Replies 5 ·
Graduate How can we see a black hole from 12.7 billion years ago?
- bassplayer142
- · Replies 16 ·
Graduate Using the solar atmosphere as a laser amplifier to extract energy
- Ruslan_Sharipov
- · Replies 3 ·
Undergrad Star Collapse: Why Not in Early Stages?
- bassplayer142
- · Replies 2 ·
Undergrad Can you calculate a star's radius from its mass, luminosity and temperature?
- Magister
- · Replies 7 ·
High School What is dark matter and why does it have such strong gravity?
- pixel01
- · Replies 4 ·
High School Did ancient people name Mars for its oceans?
- baywax
- · Replies 9 ·
Graduate Hellfire's introduction to quantum cosmology
- marcus
- · Replies 15 ·
Graduate Does Time Reversal Symmetry Apply to All Interactions?
- FizX
- · Replies 2 ·
Xena officially named Eris (as of 13 Sept)
- marcus
- · Replies 9 ·
Graduate Do Penrose and Carroll Agree on the Specialness of Conditions for Inflation?
- George Jones
- · Replies 10 ·
High School First confirmed exoplanet discovery: 51 Pegasi or PSR B1257+12?
- kop442000
- · Replies 2 ·
Undergrad Can Distance Alone Prove Gravitational Binding?
- wolram
- · Replies 3 ·
Graduate Is Earth's orbital radius stable over geological timescales?
- BillJx
- · Replies 7 ·
Undergrad Publications on the evolution of stars?
- Prairie
- · Replies 1 ·
Stargazing About Parabolic Telescope Mirrors
- Saladsamurai
- · Replies 7 ·
Graduate Homogeneous and Isotropic Stress-Energy Tensor in Cosmology
- nrqed
- · Replies 15 ·
Undergrad What are Some Important Effects or Phenomena in Astrophysics?
- soumyashant
- · Replies 1 ·
Undergrad Most distant black hole discovered 13 billion light-years away
- Astronuc
- · Replies 14 ·
Graduate Websites on lunar perturbations from differential gravity
- lewis198
- · Replies 9 ·
Graduate Debunking claims that matter and energy are identical
- saderlius
- · Replies 11 ·
Graduate Permeability of free space question
- captpaul101@hotmail.com
- · Replies 3 ·
Graduate Can Thermal Fluctuations in Loop Cosmology Solve the Horizon Problem?
- marcus
- · Replies 3 ·
Graduate Can retrocausality explain why our universe favors life?
- madness
- · Replies 19 ·
Graduate Why objects at lagrangian points 4 and 5 are stable?
- magnetar
- · Replies 4 ·
Mysterious hole discovered on Mars
- chief
- · Replies 20 ·
Graduate Does the universe's acceleration have magnitude and direction?
- blumfeld0
- · Replies 7 ·
Graduate How Do Black Holes Escape Their Own Event Horizon?
- OSalcido
- · Replies 27 ·
Graduate Is Our Observable Universe Limited by the Cosmic Horizon?
- Ricky2357
- · Replies 8 ·
Graduate HII Region Temperature Structure
- Poppop
- · Replies 4 ·
Graduate What theories appose a multiverse?
- Harmony
- · Replies 1 ·
Graduate Question regarding the arrow of time
- Nasher
- · Replies 6 ·
Graduate Black hole gravity response question
- Voltage
- · Replies 1 ·
Graduate About Hubble Radius (Radius of the Hubble sphere)
- Ricky2357
- · Replies 8 ·
Graduate Do anti-stars emit or absorb photons?
- Nasher
- · Replies 6 ·
Graduate Good books on inflation theory for beginners
- fresnelspot
- · Replies 3 ·
High School Seeing the Galilean Moons with Celestron 7x50 Binoculars
- cepheid
- · Replies 3 ·
Graduate Does the Friedmann Model Suggest an Unbounded Universe?
- da_willem
- · Replies 29 ·
Undergrad A Query on Sun and Moon Coordinate data
- lewis198
- · Replies 2 ·
Graduate Are we rewriting the birth of the solar system?
- Andre
- · Replies 1 ·
Graduate Understanding Omega: Baryons, Leptons, Photons and More
- blumfeld0
- · Replies 5 ·
Undergrad What would a black hole look like?
- MonstersFromTheId
- · Replies 6 ·
Graduate Bostrom's philosophy and Hardy's causaloids in defining the universe
- Chronos
- · Replies 59 ·
Undergrad Why are distant galaxies bluer than nearby tan galaxies?
- Jimmy Snyder
- · Replies 16 ·
Graduate What kind of energy is released when matter and antimatter collide?
- ensabah6
- · Replies 4 ·
Graduate What percent of baryonic matter is antimatter?
- ensabah6
- · Replies 1 ·
High School What colors represent different stages of a star's life cycle?
- vi3taznb0i
- · Replies 2 ·
Graduate Could Dark Energy and Dark Matter be .?
- acitizenofearth
- · Replies 9 ·
Graduate Is Gliese 581d a Habitable Super-Earth?
- marcus
- · Replies 0 ·
Undergrad Measuring the Distances to Stars and Galaxies
- McHeathen
- · Replies 4 ·
Graduate If two black holes combind together-
- magnetar
- · Replies 16 ·
Graduate Is Dark Matter More Significant Than Black Holes in the Universe's Mass?
- FrigginGenius
- · Replies 2 ·
Graduate Will the cosmic microwave background redshift beyond our horizon in trillions of years?
- blumfeld0
- · Replies 9 ·
Graduate Why Should The Atom's Form Exist At All?
- justwondering
- · Replies 3 ·
Stargazing Is the James Webb Space Telescope Ready to Replace Hubble?
- meteor
- · Replies 14 ·
High School What Can I See with My Telescope in Boston?
- Saladsamurai
- · Replies 11 ·
Ancient astronomer executed for heliocentrism who said Earth still rotates
- haiha
- · Replies 9 ·
Graduate Can gravity limit how precisely we can measure pi?
- Teresa
- · Replies 11 ·
Graduate Dark matter searches (a survey of-)
- marcus
- · Replies 1 ·
Undergrad What will the SKA study and what are job prospects there?
- Teresa
- · Replies 1 ·
Undergrad Why isn't the local group the center if everything else shows redshift?
- OSalcido
- · Replies 3 ·
Undergrad Why can we see further back than the universe's age?
- BoomBoom
- · Replies 54 ·
Graduate The Ashtekar density (you've heard of the Chandrasekhar mass, now here's )
- marcus
- · Replies 19 ·
Undergrad Interstellar Medium: Est. Mean Mass of Particle
- popffabrik1
- · Replies 1 ·
Where can I find information about black holes and their gravity?
- andrewking
- · Replies 20 ·
High School Could Dead Stars Lead to Abandoned Solar Systems?
- Frozenoak
- · Replies 12 ·
Undergrad Will a supernova 7000 light-years away outshine the sun?
- Ronhrin
- · Replies 15 ·
Graduate Where does the repulsive force in an accelerating universe come from?
- da_willem
- · Replies 19 ·
Graduate Does 1a supernova release the same amount of neutrino as type2 supernova?
- magnetar
- · Replies 1 ·
Graduate Gravitational Waves from Mergers
- RJ Emery
- · Replies 3 ·
Graduate Why Do Stars at the Edge of Galaxies Feel an Inward Pull from Dark Matter?
- Aschere
- · Replies 2 ·
Graduate Solar Cycle & Explanation for Recent Changes?
- William Astley
- · Replies 13 ·
Graduate Simulating the Future: Great Attractor 100 Billion Years Ahead
- HarryWert
- · Replies 3 ·
High School Gravitational Lensing: Learn More about Einstein Rings
- Sourabh N
- · Replies 3 ·
Undergrad What causes electrons to collapse into nuclei in neutron stars?
- madphysics
- · Replies 6 ·
Graduate Is the Universe in a State of Universal Motion?
- wilgory
- · Replies 6 ·
Undergrad Is NASA's New Evidence the Most Direct Detection of Dark Matter?
- ZapperZ
- · Replies 24 ·
Graduate How Do Accretion Discs and Black Holes Emit High-Velocity Charged Particles?
- verdigris
- · Replies 6 ·
Amazing Saturn Photo: Cassini's Awe-Inspiring Image
- setAI
- · Replies 3 ·
LCDM and Cosmology and Cosmologists
- Wallace
- · Replies 2 ·
Undergrad What does apparent magnitude mean for a 3-star system?
- Magister
- · Replies 3 ·
Graduate A hyperbolicshape of the universe, despite measurements
- Hymne
- · Replies 3 ·
Graduate Why does the Einstein cross not form a complete Einstein ring?
- Jorrie
- · Replies 3 ·
Undergrad Gravity and the Rotation of Galaxies
- sweet-stuff
- · Replies 1 ·
Undergrad Density of Gliese 581 d: What's the Real Number?
- DaveC426913
- · Replies 1 ·
Could we(entire universe) be almost nothing?
- u83rn00b
- · Replies 9 ·
Graduate Calculating Mass/Density for a 4x Larger Earth
- surfaceGravity
- · Replies 5 ·
High School Maximum number of orbiting planets
- Rothiemurchus
- · Replies 3 ·
Undergrad Why Do Comets Have Elliptical Orbits While Planets Are Circular?
- madphysics
- · Replies 9 ·