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 Which Telescope Offers the Best Value for Under $150?
- DHF
- · Replies 4 ·
Undergrad Unusual light rising from Martian surface
- Dotini
- · Replies 1 ·
Graduate Could the collapse of a black hole lead to the creation of a new Big Bang?
- BenZaleschuk
- · Replies 1 ·
Graduate Does BICEP2 kill Conformal Cyclic Cosmology?
- twistor
- · Replies 2 ·
Graduate What Are the Dynamics and Time Scales of Dark Matter Halos?
- oldGhost1
- · Replies 6 ·
Graduate How can we predict a Big Crunch?
- Yashbhatt
- · Replies 13 ·
Graduate Why do stars show absorption lines?
- zincshow
- · Replies 5 ·
Undergrad Gravitational Redshift and Hubble.
- piareround
- · Replies 17 ·
Graduate Significance of the 3K cosmic microwave background radiation
- cakeislife
- · Replies 9 ·
Undergrad Is the Mass-Luminosity Relationship for Main-Sequence Stars Linear?
- Agasthiyaraj L
- · Replies 4 ·
Graduate Black Hole Formation and Iron Distribution
- nehorlavazapal
- · Replies 5 ·
Graduate What sets the fusion rate in a main-sequence star?
- Ken G
- · Replies 5 ·
Graduate Critical density from Hubble time: what units does the formula give?
- marcus
- · Replies 1 ·
Graduate Does Dark Matter Surround Us Unseen?
- Quotidian
- · Replies 20 ·
Undergrad The Sun's End: Predicting the Inevitable
- flyinhigh
- · Replies 5 ·
Graduate How many particles could be crammed into the universe?
- Atomised
- · Replies 1 ·
Graduate Quantum perspectives in basic astrophysics?
- aim1732
- · Replies 4 ·
Time magazine spreads the horse manure
- phinds
- · Replies 43 ·
Graduate Understanding Photon Thermalization and Its Impact on CMB Anisotropies
- guest1234
- · Replies 8 ·
Graduate Orbit change due to hypothetical mass change
- meteor84
- · Replies 8 ·
Undergrad Building an n-body simulation with finite speed of gravity
- nearc
- · Replies 12 ·
Graduate Are Modifications Needed for Escape Velocity in Elliptical Orbits?
- vikasagartha
- · Replies 6 ·
Graduate How to Plot a Map Using Healpix and Real Data?
- fineTuner
- · Replies 16 ·
Undergrad Expansion of space vs stuff just moving away
- imsmooth
- · Replies 70 ·
Graduate Help understanding the Friedmann equations?
- Misplaced
- · Replies 3 ·
Undergrad Smallest Body Possible to Have Rings
- 3point14rat
- · Replies 8 ·
Graduate Primordial B modes discovery press conference
- Greg Bernhardt
- · Replies 78 ·
Graduate Near black hole event horizon time dilation?
- darkhorror
- · Replies 1 ·
Undergrad Do stars form more easily in cool or hot dense nebulae?
- Sastronaut
- · Replies 8 ·
Graduate How does a solar flare cause a magnetic crochet?
- Dotini
- · Replies 1 ·
High School Can Sun's Gravity Alter Earth's Landscape Over Billions of Years?
- us40
- · Replies 2 ·
Undergrad Were we really created from supernovas?
- Chris42393
- · Replies 4 ·
Undergrad The weak force, first step of nuclear fusion in the Sun
- bluejello
- · Replies 5 ·
Graduate Where did my 65 kg mass come from at Planck time?
- big_bounce
- · Replies 1 ·
Graduate Why not a flat but finite spatial universe?
- nomadreid
- · Replies 17 ·
Graduate Superkick effect: why merging black holes can be ejected from galaxies
- D H
- · Replies 9 ·
Which software is used for creating simulated cosmic systems?
- rmfw
- · Replies 4 ·
High School Why Do Only Gas Giants Have Rings?
- DHF
- · Replies 18 ·
Graduate What explains the fine-tuning of 35 cosmological parameters?
- rasp
- · Replies 19 ·
Graduate When was (or will be) inflation confirmed?
- the_pulp
- · Replies 8 ·
Undergrad Will there be a normal force on a ball on a table in a stationary spaceship?
- shreder
- · Replies 21 ·
Graduate Could Pluto and its moons be a collisional family?
- |Glitch|
- · Replies 5 ·
Graduate What if the Gravitational Constant were larger?
- Columbus
- · Replies 1 ·
Exciting Future Space Missions: JWST and New Horizons on the Horizon!
- Cosmobrain
- · Replies 5 ·
Undergrad Rings discovered around Centaur asteroid Chariklo
- Dotini
- · Replies 2 ·
Graduate If G is constant, why didn't the early universe collapse?
- Stonius
- · Replies 10 ·
Graduate Time, energy, information constants
- jgreene
- · Replies 3 ·
Undergrad Astronomy Day is coming at my university; any suggestions for demos?
- SupernerdSven
- · Replies 11 ·
The Open Astronomy Journal publishing history and reputation
- Nereid
- · Replies 20 ·
Graduate How do we know the uncertainty principle is real and not just experimental error?
- Quarlep
- · Replies 24 ·
Graduate Can top rungs replace bottom ones in cosmic distance ladder?
- geoduck
- · Replies 5 ·
Undergrad The elliptical orbits and inverse-square law forces.
- d-richard
- · Replies 3 ·
Graduate Regaining Causal Contact by passing Event Horizons
- craigi
- · Replies 6 ·
Graduate Does dark energy interact with matter?
- oldGhost1
- · Replies 15 ·
Graduate Is there a density point which reduces anything to a black hole?
- delsaber8
- · Replies 13 ·
Graduate Does time's flow create space as a field?
- Kenn.Guilstorf
- · Replies 11 ·
High School Can atoms move from place to place without passing the space
- soqrat
- · Replies 1 ·
Stargazing ALMA vs James Webb: Which telescope will reveal more about the universe?
- revo74
- · Replies 4 ·
Graduate Understanding Superhorizon Dynamics in Cosmology: A Mathematical Perspective
- the_pulp
- · Replies 2 ·
High School How much of the night sky one could see from various locations
- EskWIRED
- · Replies 9 ·
Undergrad Does time slow down with Earth's motion through space?
- nycoh
- · Replies 1 ·
Graduate The Fastest-Approaching Object in the Universe
- CygnusX-1
- · Replies 8 ·
Graduate Metal packing structure and curved space
- craigi
- · Replies 8 ·
Undergrad What substance could potentially flow and pool on the surface of Venus?
- Terdbergler
- · Replies 4 ·
High School How long would it take for an asteroid to travel to our sun-system ?
- Anonymous_1
- · Replies 2 ·
Undergrad Cosmology vs. Physical Cosmology
- pierce15
- · Replies 1 ·
Undergrad How likely is it that Europa has life under its icy surface
- AdrianHudson
- · Replies 15 ·
High School How do we know how old the universe is?
- Anonymous_1
- · Replies 4 ·
Graduate The Measure Problem and the Youngness Paradox
- Salamon
- · Replies 1 ·
Graduate A thermal expansion coefficient of spacetime?
- ryan albery
- · Replies 16 ·
Graduate B-mode plots, spherical harmonics?, fundamental modes?
- Spinnor
- · Replies 1 ·
Graduate How is dark energy different from homogeneous tidal forces?
- Glurth
- · Replies 10 ·
Undergrad Why are the nearest stars to Earth mostly red dwarfs?
- Sastronaut
- · Replies 7 ·
Graduate How Does the BICEP Measurement Indicate Inflation Near the GUT Scale?
- the_pulp
- · Replies 7 ·
Graduate Remove Pupil Ghost using IRAF rmpupil
- abbeynewton
- · Replies 2 ·
Graduate Falling matter of supernova does work heating the core?
- Spinnor
- · Replies 3 ·
Graduate The Horizon Problem: Explaining Universe Isotropy
- alvallis
- · Replies 4 ·
Graduate Space/time curvature of the young universe?
- EskWIRED
- · Replies 7 ·
Graduate Understanding Primordial B-modes and Cosmic Inflation
- connorp
- · Replies 4 ·
Graduate About a spacecraft trip to the asteroids
- Emspak
- · Replies 3 ·
Graduate Last scatter by e-, light looks hotter, cooler, time, wavelength.
- Spinnor
- · Replies 6 ·
Graduate How could inflation interact with recombination radiation?
- wmikewells
- · Replies 8 ·
Graduate CMB polarization data plots, almost a vector field, then what?
- Spinnor
- · Replies 3 ·
Undergrad Are Black Holes Necessary for the Universe to Function?
- Nugso
- · Replies 11 ·
Pluto found larger than Eris in new analysis
- CygnusX-1
- · Replies 3 ·
High School What does the universe look like today if we could see it in real time?
- flyinhigh
- · Replies 5 ·
Graduate Closed, collapsing universe+only photons at first -> matter when hot?
- Spinnor
- · Replies 6 ·
Undergrad The magnitude of Earth from Moon
- Numeriprimi
- · Replies 13 ·
High School Indulge a poet a few questions about Big Bang?
- mrblint
- · Replies 5 ·
Graduate Why is a non-rotating object moving in a circle impossible?
- jtban
- · Replies 21 ·
Graduate Hawking radiation and information
- acesuv
- · Replies 4 ·
Graduate Can a thimbleful of neutron star material cause damage to Earth?
- Mr.Aaron
- · Replies 10 ·
Undergrad Is moon dust hazardous from UV or cosmic radiation exposure?
- bwinter
- · Replies 3 ·
Graduate Primordial black holes ruled out as dark matter candidate
- Chronos
- · Replies 11 ·
Undergrad Antimatter recreating the big bang
- Manraj singh
- · Replies 12 ·
Graduate How does the expansion of space affect the direction of time?
- Geordie Ross
- · Replies 9 ·
Graduate Where does Space time come from?
- jaiii
- · Replies 1 ·
Graduate Why doesn't the sun's rotation align with the invariable plane?
- anorlunda
- · Replies 4 ·
Graduate Fast/slow Alfven waves in High/Low Beta Plasma?
- Alita1984
- · Replies 6 ·
Undergrad Can a hypernova explosion last for years?
- bobie
- · Replies 4 ·