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 Cell phones used to detect cosmic rays worldwide
- Hornbein
- · Replies 3 ·
High School "WT1190F" is the name for space junk that will hit Earth
- jim mcnamara
- · Replies 2 ·
Experience the Milky Way via 46 billion pixels
- jedishrfu
- · Replies 3 ·
Graduate Why Are Subterranean Colonies Rarely Proposed in Space Colonization Scenarios?
- #Thomas#
- · Replies 7 ·
Graduate Does a rigid box of gas cool over cosmological timescales?
- jcap
- · Replies 1 ·
Graduate When Did We Last Get a Glimpse of the Big Bang?
- Helios
- · Replies 34 ·
Calculate the Gravity of a Black Hole
- ZavraD
- · Replies 6 ·
Graduate Orbit Dynamics in an Expanding Universe
- Buzz Bloom
- · Replies 17 ·
High School Questions about black holes and gravity
- Kenneth Korsmo
- · Replies 76 ·
Undergrad How was Galileo able to observe Venus's phases?
- TheExibo
- · Replies 6 ·
High School How Are Black Holes Formed and What Are Their Key Facts?
- haileyparikh
- · Replies 34 ·
High School Where Do Wormholes Take Us in Space and Time?
- astrophysicskid
- · Replies 1 ·
Graduate What happens to a seesaw extending to another galaxy if one end moves at 100 mph?
- PhysicsFan11
- · Replies 25 ·
What Would a Trip from Earth to Orion Look Like?
- tony873004
- · Replies 1 ·
Graduate Origins of the Fundamental Interactions/Forces
- HeavyWater
- · Replies 3 ·
Nice ongoing planetary alignment
- Bandersnatch
- · Replies 1 ·
Undergrad Juno Flyby Anomaly - Searching for Answers
- nearc
- · Replies 8 ·
Undergrad Could an infinite universe ever end?
- Einstein's Cat
- · Replies 6 ·
Graduate How can light have momentum if it has zero mass?
- bcrowell
- · Replies 6 ·
Graduate Is a Magnetic Levitation Space Launcher Possible?
- msinclairinork
- · Replies 11 ·
Graduate Is Multiverse proven by Plank data?
- Alexis1304
- · Replies 4 ·
Graduate Metric expansion misunderstanding
- Lanniakea
- · Replies 13 ·
High School Could Mars's seasonal streaks be water or another liquid?
- newjerseyrunner
- · Replies 1 ·
Graduate Is the Universe's Expansion Actually Slowing Down?
- jssamp
- · Replies 6 ·
Graduate MOND and the missing baryons problem
- wolram
- · Replies 41 ·
High School What are the ways we can search for alien life?
- @PK nd
- · Replies 62 ·
Graduate No Dark Matter or gravity modification for flat rot
- wolram
- · Replies 5 ·
High School Software to simulate lunar orbit changes and effects on Earth's day-night cycle
- AHashemi
- · Replies 2 ·
Proper motion of Ursa Major (Big Dipper)
- tony873004
- · Replies 2 ·
Graduate Gravitational lensing as a way of observing Milky Way?
- SheriffPeabody
- · Replies 6 ·
Graduate The Inflaton Field And Repulsive Gravity
- BOAS
- · Replies 13 ·
High School How much force to accelerate a million-pound rock to 1g in one hour?
- marmstrong941
- · Replies 26 ·
Graduate Could the universe undergo cyclic expansion and contraction?
- halpmaine
- · Replies 9 ·
Graduate Why does Saturn have less helium than other gas giants?
- JDoolin
- · Replies 6 ·
High School What Are the Physical Limitations of a Dyson Sphere?
- Justice Hunter
- · Replies 5 ·
Graduate Does time remain consistent across the universe if mass varies?
- pnorris2000
- · Replies 2 ·
Graduate Heliocentric polar orbit crossing the Earth's orbit twice
- xpell
- · Replies 8 ·
Graduate Is the universe fine tuned for life
- wolram
- · Replies 21 ·
Graduate Collision of massive star with black hole
- Johninch
- · Replies 13 ·
Undergrad Kepler's 2nd across a system of planets
- tfr000
- · Replies 4 ·
High School Suggest a Quantum Physics Book for a 16 Year Old
- ayush solanki
- · Replies 6 ·
Graduate Question re Galaxy Rotation Curve
- Buzz Bloom
- · Replies 3 ·
Graduate Where is the mass of a black hole actually located?
- Nemika
- · Replies 8 ·
Graduate Likelihood of confirming past life on Mars
- dilletante
- · Replies 6 ·
Undergrad Cosmology looks beyond the standard model
- wolram
- · Replies 3 ·
High School Why is Venus hot and how much sunlight would cool it down?
- marmstrong941
- · Replies 3 ·
Graduate Consequences of Overlapping Event Horizons in Supermassive Black Hole Mergers
- FredrikJ
- · Replies 4 ·
Graduate What happens to matter when it enters a black hole?
- RealTwistedTwin
- · Replies 12 ·
Is the Celestron Omni XLT 120 Refractor Telescope worth the investment?
- DaveC426913
- · Replies 7 ·
Undergrad How do you calculate the density of the universe?
- AleksanderPhy
- · Replies 7 ·
Graduate Can Neutrons Emit Light Without Electrons to Swoosh Them Away?
- Low-Q
- · Replies 22 ·
Graduate The Universe Never Expands Faster than the Speed of Light
- Chalnoth
- · Replies 11 ·
Undergrad At what speed is our universe expanding?
- Shafat Hasan
- · Replies 18 ·
Undergrad Does an Expanding Universe Alter How Quickly Light Travels Through Space?
- Gal
- · Replies 2 ·
Graduate Will a bouncing cosmology lose information
- wolram
- · Replies 12 ·
Graduate Why Does Increased Baryon Loading Shift Power Spectrum to Higher Multipoles?
- gluon
- · Replies 1 ·
Graduate What Happens to Electrons in Synchrotron Radiation?
- shirin
- · Replies 2 ·
Graduate Are Atoms Just Empty Space If Fundamental Particles Are Zero-Dimensional?
- Nav
- · Replies 12 ·
Graduate Horizon complementarity between de Sitter and Minkowski space
- slatts
- · Replies 7 ·
Graduate What Is the Impact of Shape on Escape Velocity in an Expanding Universe?
- Buzz Bloom
- · Replies 8 ·
Graduate Why should the Bullet Cluster focus light?
- Earnest Guest
- · Replies 35 ·
Undergrad Understanding Observing Frequency and Its Significance in Radio Astronomy
- shirin
- · Replies 5 ·
Stargazing What are the upper physical resolution limits on telescopes?
- BWV
- · Replies 7 ·
Graduate Do radio and X-ray galaxies differ by redshift or emission mechanism?
- shirin
- · Replies 6 ·
Graduate First detection of direct collapse black holes?
- Chronos
- · Replies 2 ·
Graduate Possible to derive an approximation of G from a Saros ?
- Isaacsname
- · Replies 2 ·
High School Does flowing water on Mars mean life is possible?
- @PK nd
- · Replies 6 ·
Undergrad Does the black matter has weight?
- Nemika
- · Replies 1 ·
Graduate What does the Friedmann equation tell you and what are its terms?
- AleksanderPhy
- · Replies 4 ·
Graduate What can the Anthropic Principal predict?
- Buzz Bloom
- · Replies 2 ·
Graduate Event Horizons = Cosmological Horizons?
- Salamon
- · Replies 19 ·
Graduate Confusion re Laniakea Super Cluster
- Buzz Bloom
- · Replies 1 ·
Undergrad Dependence of rotational angular velocity of planets
- Abhirikshma
- · Replies 2 ·
Graduate What is the purpose of the Einstein stress-energy tensor?
- AleksanderPhy
- · Replies 1 ·
Undergrad Why are photons affected by gravity?
- ayush solanki
- · Replies 8 ·
Undergrad About doubling the mass of the planets and the sun of our solar system
- ayush solanki
- · Replies 10 ·
Graduate How Does Synchrotron Radiation Influence Observations in Radio Astronomy?
- shirin
- · Replies 2 ·
Graduate Radiation from the surface of a star
- jorgeavg
- · Replies 6 ·
Graduate Gas Mass Calcuation in Galaxy Cluster
- Earnest Guest
- · Replies 3 ·
Stargazing Why Aren't There Telescopes on the Moon?
- Gerinski
- · Replies 115 ·
Graduate Spaghettification and gravity in theory of relativity?
- Pejeu
- · Replies 1 ·
Graduate Are Interstellar Extinction Variations Misleading Cosmological Measurements?
- wolram
- · Replies 1 ·
Graduate Time at the big bang and in very early time after that
- Prins
- · Replies 2 ·
Graduate Population 1 vs Population 2 Stars: Metal Rich vs Metal Poor
- Shivansh Mathur
- · Replies 1 ·
Graduate Is the X-Ray Mass of the Coma Cluster Accurately Measured?
- Earnest Guest
- · Replies 2 ·
George Will endorses space research
- gleem
- · Replies 1 ·
Graduate Random Walk Question re Inflation
- Buzz Bloom
- · Replies 8 ·
Graduate Does the Bullet Cluster Disprove MOND and Challenge ΛCDM?
- Earnest Guest
- · Replies 41 ·
Graduate Origin of Quantum Perturbations?
- slatts
- · Replies 15 ·
Graduate Good 1st year grad level texts in galaxies and cosmology
- CosmicDestiny
- · Replies 1 ·
Graduate How Does the CMB Frame Differ from Other Frames in Relativity?
- palmer eldtrich
- · Replies 8 ·
High School I've heard gravity can "fling" stuff, how does this work?
- Coolamebe
- · Replies 6 ·
Graduate Computing osculating orbital elements
- cptolemy
- · Replies 4 ·
Graduate How many hypothetical particles do we need
- wolram
- · Replies 5 ·
Undergrad Why can dark matter make our planets move in same velocity?
- Space Dragon
- · Replies 11 ·
Graduate Fine tuning, muitverse and a double standard
- palmer eldtrich
- · Replies 10 ·
Graduate How does gravity get out of a black hole?
- nburns
- · Replies 4 ·
Graduate Destruction of Solar System by passing Star
- Hornbein
- · Replies 14 ·
Graduate What is the evidence for dark matter in the solar neighborhood?
- wolram
- · Replies 7 ·
Graduate How Do Scientists Determine the Composition of a Star's Core?
- Jimmy87
- · Replies 3 ·