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 Effect of Rotation on the Earth and Planetary Disk(s)
- Mazin Nasralla
- · Replies 8 ·
Graduate How Do Planetary Distances Influence Retrograde Motion Durations?
- RingNebula57
- · Replies 3 ·
High School Why are two masses attracted to each other by gravity?
- tanmay
- · Replies 2 ·
Graduate Marginal evidence for cosmic acceleration from Type Ia SNe
- Garth
- · Replies 93 ·
Graduate Infinite Universe and Parallel Universes
- RyanH42
- · Replies 35 ·
Graduate Could Lee Smolin's Fecund Universes Theory Solve Black Hole Information Paradox?
- ricardo81
- · Replies 2 ·
Undergrad Difference between conductors and empty space
- carllacan
- · Replies 1 ·
Are Multiverses and Intelligent Life More Than Just Beliefs?
- Lamonte Johnson
- · Replies 1 ·
Undergrad What would it be like to be at a Lagrange Point?
- PPERERA
- · Replies 4 ·
Graduate Speed and / or expansion rate of the Universe?
- Shafat Hasan
- · Replies 2 ·
Graduate Could stellar winds and galactic gas pressure cause cosmic expansion?
- FallingSky
- · Replies 10 ·
Graduate How does gravity cause cosmic deceleration in a flat universe?
- yogi
- · Replies 10 ·
Graduate Lizzie time unit for cosmological timescales
- marcus
- · Replies 23 ·
Graduate How Can I Measure Stellar Aberration Accurately?
- jk1956
- · Replies 6 ·
Graduate How many interstellar exocomets per cubic lightyear and what's the capture probability?
- Aaron8547
- · Replies 5 ·
Graduate Gravitational attraction between two atoms
- Dmitry Tyurev
- · Replies 26 ·
Graduate Evidence that time and space began at the instant of the big
- serp777
- · Replies 8 ·
Graduate Star post-main sequence timescale
- Sherrod
- · Replies 4 ·
Graduate Test set-up for full dark matter simulation
- ohannuks
- · Replies 4 ·
Stacking 204 RAW frames for deep-sky astrophotography
- Andy Resnick
- · Replies 3 ·
Graduate Does the expansion of the universe preserve thermal equilibrium?
- m_robertson
- · Replies 10 ·
Undergrad Venus Transit - What should be a simple problem
- Mazin Nasralla
- · Replies 6 ·
High School Need to exchange a helical focuser for a rack and pinion one
- rodentraiser
- · Replies 5 ·
High School How large an area is that brightly illuminted patch from stars covering?
- james gander
- · Replies 17 ·
Graduate Properties of an evolved universe
- McGarr
- · Replies 4 ·
Graduate Could energy be extracted from spacetime expansion?
- Gerinski
- · Replies 1 ·
Graduate Can the CMB Reference Frame be Changed in the Newtonian Friedmann Equation?
- Mysteryciel
- · Replies 21 ·
Graduate 814 Ghostly Galaxies in the Coma Cluster
- CygnusX-1
- · Replies 1 ·
Graduate Radiation dominated universe in Newton's approximation (no )
- Mishra
- · Replies 8 ·
Graduate Timeline of inflation and perturbation re-entry in early universe
- JJNic
- · Replies 4 ·
Graduate Age of universe -- Probability why it is so young?
- tom aaron
- · Replies 44 ·
High School Will the Voyager Golden Records withstand the harshness of space?
- arunshanker
- · Replies 20 ·
Graduate Does the Equation 1=Ω_k+Ω_m+Ω_Λ Hold for All Universe Types?
- Mysteryciel
- · Replies 4 ·
Graduate Chemical potential equilibrium cosmology
- center o bass
- · Replies 3 ·
Graduate Where can I find observed mass and radius data for white dwarfs?
- ORF
- · Replies 5 ·
Graduate Hubble redshift and calculation of galactic rotation curves
- ConformalGrpOp
- · Replies 3 ·
Graduate Early universe black holes and LCDM's age problem
- Garth
- · Replies 6 ·
Graduate Adiabatic perturbations -- why the name?
- center o bass
- · Replies 2 ·
Graduate Why Does Everything in the Universe Rotate?
- somebodyelse
- · Replies 47 ·
Graduate Integrated Boltzman equation for dark matter
- karlzr
- · Replies 1 ·
Graduate Recent Early Universe Cosmology Review - Funding Essay
- lasm2000
- · Replies 5 ·
Graduate Interpretting the cosmological constant
- bjb406
- · Replies 1 ·
Graduate The impossible early galaxy formation
- wolram
- · Replies 1 ·
Undergrad Pluto's moon Nix and its wild tumbling orbit
- davenn
- · Replies 3 ·
Graduate Does universe expansion create new points in space?
- spaceman spiff
- · Replies 4 ·
Undergrad Will future stars create new elements through evolution?
- elusiveshame
- · Replies 13 ·
Graduate Massive primordial tensor perturbations?
- 302021895
- · Replies 2 ·
Undergrad Plasma tubes floating above Earth
- jedishrfu
- · Replies 4 ·
Graduate Understanding Solar UV Radiation and Its Impact on Earth: A Brief Overview
- neilparker62
- · Replies 3 ·
Graduate Functional dependence of the size of the visible universe
- A. Neumaier
- · Replies 6 ·
Graduate Are Primordial Black Holes Still a Viable Candidate for Dark Matter?
- newjerseyrunner
- · Replies 5 ·
Undergrad Is it theoretically possible for a star to orbit a planet?
- RisingSun361
- · Replies 17 ·
Stargazing Can't see anything through Levenhuk Strike 120 reflector telescope?
- SofiaMo
- · Replies 11 ·
Graduate Is Deja Vu the Brain's misinterpretation of Spacetime?
- mero55
- · Replies 3 ·
Undergrad Milky Way Mass: 60,000 Ly from Galactic Center
- ViperSRT3g
- · Replies 3 ·
Graduate What's wrong with this probability argument against the Big Bang?
- Mark D
- · Replies 2 ·
Undergrad Are proton and electron numbers balanced in the universe?
- Stephanus
- · Replies 16 ·
I just saw a fireball and nobody cares
- DaveC426913
- · Replies 9 ·
Undergrad Does Inflation Refer to the Expansion of Space or the Entire Universe?
- CassiopeiaA
- · Replies 21 ·
Graduate Does Isotropy Necessarily Imply Homogeneity in the Universe?
- ChrisVer
- · Replies 2 ·
Graduate Star Nuclear Reaction: P+P, D+P, He3 and CNO Cycle
- Stephanus
- · Replies 2 ·
Undergrad Why do small bodies stay in orbit around large bodies?
- Jireat
- · Replies 5 ·
Graduate Sky temperature profiles and black body radiation
- lostminty
- · Replies 1 ·
Graduate Emergence of much smaller stars in early Universe?
- AtomicPunk
- · Replies 6 ·
Graduate Where Does the 10^-35 s^-2 Cosmological Constant Value Come From?
- Thomas Moore
- · Replies 13 ·
Graduate Excluding the Standard Model from Dark Matter?
- Quds Akbar
- · Replies 2 ·
Graduate Article with good analysis of different models?
- Ans
- · Replies 3 ·
Graduate Did a Giant Impact Make the Martian Moons?
- CygnusX-1
- · Replies 2 ·
Graduate Is There Evidence of a Type Ia Supernova Formed via the Single Degenerate Mode?
- Chronos
- · Replies 1 ·
Graduate Can a black hole become a white hole if it accumulates too much matter?
- edenk
- · Replies 13 ·
Graduate What is the limit of classical GR in describing the singularity of a black hole?
- Stephanus
- · Replies 9 ·
Undergrad Is the Density of Points in an Interval Twice as Much with Double Length?
- Stephanus
- · Replies 7 ·
Undergrad Physical significance of permittivity of free space and its F/m units
- wasi-uz-zaman
- · Replies 4 ·
Graduate How Do Direct Collapse Black Holes Form in the Early Universe?
- Chronos
- · Replies 50 ·
Undergrad Are Asteroids Formed by Collisions or Accretion?
- Lamonte Johnson
- · Replies 4 ·
Graduate Where Can I Access a Database for Universe Mass Distribution and Movement?
- Omega0
- · Replies 1 ·
Graduate CMB photons, why are they still around?
- Gerinski
- · Replies 15 ·
Graduate Where do things go after they were sucked by a Blackhole?
- at94official
- · Replies 57 ·
Micrometeorite caught on camera in Oklahoma?
- mp3car
- · Replies 3 ·
Graduate Why did gas cloud G2 avoid capture by Sagittarius A*?
- EinsteinKreuz
- · Replies 9 ·
Graduate Geosynchronous satellite altitudes on Mars and Ceres
- marcus
- · Replies 32 ·
Graduate How to calculate the Age of the Universe, from observations
- marcus
- · Replies 6 ·
High School Is this picture correct about the CNO cycle?
- Stephanus
- · Replies 4 ·
Graduate Is Matter/Energy Eternal? Mechanisms for an Endless Universe?
- Deepak K Kapur
- · Replies 24 ·
Can You Spot All the Galaxies in This Virgo Supercluster Photo?
- Andy Resnick
- · Replies 8 ·
Graduate Trajectory opimization: Fast preview algorithm
- Profiler
- · Replies 1 ·
Undergrad Can Kepler's 2nd Law be applied to more than one planet?
- Overt
- · Replies 6 ·
Graduate Other evidences of the Galaxys' Acceleration
- meTheNaive
- · Replies 1 ·
Graduate What does it mean by a flat universe?
- Happiness
- · Replies 13 ·
Undergrad Does the barycenter or the sun sit at the focus in Kepler's first law?
- RisingSun361
- · Replies 1 ·
Graduate Can We Harness Black Holes for Faster Flybys?
- Dr Wu
- · Replies 2 ·
Graduate Four random quasars in a straight line?
- jimgraber
- · Replies 6 ·
Graduate When can globular clusters be considered collisionless?
- kderakhshani
- · Replies 4 ·
Graduate Distances for classical objects vs. photons
- TRB8985
- · Replies 10 ·
Graduate Can you have an antimatter black hole?
- Philjhinson
- · Replies 18 ·
Graduate Friedmann equation reformulated for volume growth rate instead of distance
- marcus
- · Replies 18 ·
Helpful websites about astronomy and cosmology
- Phobos
- · Replies 144 ·
High School Are Galaxies in Hubble Telescope Photos of Clusters?
- synfiniti
- · Replies 2 ·
Graduate Can Anti Matter Galaxies and Black Holes Exist Together?
- Stephanus
- · Replies 12 ·
Graduate Center of mass - cant find error in derivation
- Kyouran
- · Replies 13 ·