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
Undergrad Redshift - does energy fade or get absorbed?
- Corkie2003
- · Replies 5 ·
Graduate Would an Object Fall Straight Through a Hole in a Spinning Planet?
- Dmstifik8ion
- · Replies 5 ·
Graduate How do dwarf galaxies form?
- vincentm
- · Replies 1 ·
Undergrad Light years-distance or light travel time?
- Chip Orr
- · Replies 3 ·
Undergrad Proving Venus's Orbit is 0.72x Earth's: Understanding Greatest Elongation
- ahirschey
- · Replies 2 ·
Undergrad Can Gravity Create a Perpetual Motion System in Planetary Orbits?
- neurotic
- · Replies 6 ·
Graduate Why is the Poincaré dodecahedron not observed in the universe?
- fmichel
- · Replies 17 ·
Graduate Scalar field pressure and energy density
- S.P.P
- · Replies 4 ·
Undergrad Horizontal system of celestial coordinates
- suedenation
- · Replies 1 ·
Orion Atlas 11 telescope arriving soon
- russ_watters
- · Replies 24 ·
Graduate How was cosmic background radiation generated and what does it reveal?
- marlon
- · Replies 25 ·
Undergrad Gravitational pull is related to rotational speed?
- waterchan
- · Replies 3 ·
Undergrad What Is the Significance of Zero Right Ascension in Astronomy?
- chill85
- · Replies 1 ·
Graduate Do galaxies have a negative mass defect?
- kmarinas86
- · Replies 2 ·
Graduate This universe would expand right?
- aquabug918
- · Replies 11 ·
Graduate Inflationary Theory out of thin air?
- Chaos' lil bro Order
- · Replies 33 ·
Book recommendations for cosmology and modern physics
- student007
- · Replies 7 ·
Graduate Expanding Universe (an interestin mind experiment)
- pfontec
- · Replies 4 ·
Undergrad Measuring the absolute value of the AU
- Alvin
- · Replies 1 ·
Graduate Does the Maximum Entropy of a Black Hole Allow for Hawking Radiation?
- TriTertButoxy
- · Replies 1 ·
Graduate The possiblity of a solid planetary disk
- Loren Booda
- · Replies 18 ·
Graduate How to Solve Tolman-Oppenheimer-Volkov Equations for Neutron Stars?
- Karliski
- · Replies 3 ·
Graduate Mass of Black Holes: Measuring the Unmeasurable?
- zero12104
- · Replies 2 ·
Graduate Why doesn't the universe expand as a sphere?
- Arithus
- · Replies 13 ·
High School When does Cruithne return to Earth's orbit?
- thenodfather
- · Replies 2 ·
High School Earth's Celestial Poles: North and South
- chill85
- · Replies 1 ·
Graduate The Supernova Legacy Survey (SNLS)
- Astronuc
- · Replies 3 ·
Graduate No HUP, a universe without unknowns?
- David Burke
- · Replies 18 ·
Graduate A question on the rate of time in the Light we observe
- popfuzz
- · Replies 2 ·
Graduate New Nature Paper: Old Ia Supernovae different?
- George Jones
- · Replies 4 ·
Will NASA's Hubble Servicing Mission Save the Telescope?
- russ_watters
- · Replies 1 ·
Black spot visible in photos of the sun from April 2006
- mik0930
- · Replies 2 ·
Graduate Why Can't I Solve This Kepler's Law Problem Correctly?
- takoma
- · Replies 1 ·
Graduate Are Extreme Internal Accelerations Significant in the Inflationary Universe?
- oldman
- · Replies 3 ·
Graduate Is dark matter just an illusion?
- Mk
- · Replies 21 ·
Graduate What Causes a White Dwarf Star to Exceed the Chandra Mass Limit and Explode?
- Labguy
- · Replies 4 ·
Stargazing I want to build my telescope any advice ?
- ranroun
- · Replies 5 ·
High School Astronomy in West LA: Can You Observe with a Telescope?
- Quaoar
- · Replies 5 ·
Undergrad How Big Would A Planet Have To Be To Have Earth's Gravity?
- SAZAR
- · Replies 17 ·
Graduate How can a neutronstar that only consists of neutrons
- Hymne
- · Replies 6 ·
Undergrad Physical properties of objects that orbit each other in the universe
- judi6070
- · Replies 2 ·
Graduate Why is HAT-P-1 so much larger than expected?
- Astronuc
- · Replies 3 ·
Can you see orange sunset clouds from space?
- ncr7
- · Replies 10 ·
Graduate Why do double lobed radio galaxies and Seyfert galaxies have similar energy sources?
- blumfeld0
- · Replies 1 ·
Undergrad !Evidence of Star Formation in Molecular Clouds
- blumfeld0
- · Replies 5 ·
Undergrad What if objects go toward each other rather than away
- Skhandelwal
- · Replies 2 ·
Can you photograph a satellite through a telescope with a handheld camera?
- DaveC426913
- · Replies 34 ·
Undergrad Why do Jupiter's atmospheric bands move at different speeds?
- argonurbawono
- · Replies 3 ·
Graduate Can Light Be Multiply Scattered in the Universe?
- oldman
- · Replies 5 ·
Stargazing Upgrading from small dobsonian to a larger telescope for astrophotography
- vincentm
- · Replies 19 ·
Graduate The cross section of a photon traversing the observable universe
- Loren Booda
- · Replies 16 ·
Graduate Supernova 1987a, light, neutrinos, VSL claims
- danriley
- · Replies 17 ·
Graduate New double pulsar testbed for GR and alts.
- marcus
- · Replies 0 ·
Graduate CP violation and element forging
- Pavel
- · Replies 17 ·
Graduate Can gravitational lensing detect dark matter?
- ham 'n eggs
- · Replies 1 ·
Graduate Gravity On Earth Dependant On Distance From Center
- Darwin
- · Replies 8 ·
What created the big bang if the big bang created the universe?
- unscientific
- · Replies 43 ·
Graduate Just an idea I've been going over.
- Arithus
- · Replies 2 ·
Graduate How Do You See Spectral Lines in Near IR from the Sun?
- rp895
- · Replies 1 ·
Graduate Tiny Blackholes may pervade space
- vincentm
- · Replies 7 ·
High School What was the pole star 9,000-10,000 BC?
- Myra759
- · Replies 18 ·
Graduate Wet planets common (new simulation study by Raymond et al)
- marcus
- · Replies 0 ·
Graduate What Is the Role of Vacuum Fluctuations in the Universe's Origin?
- RAD4921
- · Replies 3 ·
High School Should gas giants count as planets?
- Aquafire
- · Replies 7 ·
Undergrad Sedna must be a planet (at least for now) according to new definition?
- ACG
- · Replies 7 ·
Graduate Superluminal Matter at Two Stages of Big Bang ?
- berkeman
- · Replies 1 ·
How Big is Earth Compared to the Sun?
- JamesU
- · Replies 18 ·
Earth Narrowly Escapes 2006 QM111 Asteroid Flyby
- tony873004
- · Replies 5 ·
Graduate Research Project Ideas - Taylor's Brainstorming
- TmanMrT
- · Replies 3 ·
The Astronomy Peer Review Process
- VikingF
- · Replies 12 ·
Graduate How do dark energy candidates like quintessence differ from the cosmological constant?
- Jan Janssens
- · Replies 1 ·
Interested in The Sky at Night webcasts?
- Kurdt
- · Replies 1 ·
Will a Satellite Crash into the Moon Tonight?
- DaveC426913
- · Replies 8 ·
Undergrad Why does higher density of the early universe result in a faster expansion rate?
- lwymarie
- · Replies 2 ·
Graduate How Does Precession Relate to Hindu Scriptures and Ancient Astronomy?
- navneet1990
- · Replies 4 ·
Graduate What evidence supports the Big Bang theory beyond galactic redshift?
- Neohaven
- · Replies 15 ·
Graduate Arrow of Time Forbids a Positive Cosmological Constant
- marcus
- · Replies 5 ·
Graduate Why don't Saturn's rings condense into a moon?
- FeynmanMH42
- · Replies 4 ·
Undergrad How close can planets safely exist from each other?
- ghost77
- · Replies 1 ·
High School Do All Planets Have Moons and How Did They Form?
- ghost77
- · Replies 1 ·
High School Is Space Just a Magnified Illusion of a Fluid Universe?
- soft_rain
- · Replies 6 ·
Graduate Can the Universe Be Understood as a Two-Dimensional Model?
- Futobingoro
- · Replies 3 ·
Graduate Is Infinity Possible? A Discussion on Hawking's Theories of the Universe
- Born2Perform
- · Replies 27 ·
Rare Astronomical Event Observed for the First Time
- neutrino
- · Replies 1 ·
Popular Cosmology Books - Which to Buy or Not?
- wolram
- · Replies 3 ·
Graduate Wolfgang Priester forsaw Big Bounce cosmology
- marcus
- · Replies 1 ·
High School Why Is Pluto No Longer Considered a Planet?
- poppop24
- · Replies 5 ·
Graduate Could Quasar Activity Explain the Distribution of Dark Matter in Galaxies?
- FeynmanMH42
- · Replies 7 ·
Graduate Was the Singularity Rotating at the Time of the Big Bang?
- jowjowman
- · Replies 10 ·
High School Why don't we feel Earth's motion around its axis, sun and galaxy?
- mistersmith
- · Replies 6 ·
High School Mars Closest Encounter With Earth
- bioginz
- · Replies 1 ·
Undergrad Universe could be Bigger and Older - Move over 13.7 Gy
- neutrino
- · Replies 29 ·
Graduate Could ordinary matter account for dark matter instead of exotic particles?
- oldman
- · Replies 22 ·
Graduate Investigating an Unknown Hypothesis on Gravity Unequality
- Werg22
- · Replies 1 ·
Undergrad Scaling limiting magnitude from 16-inch to 12-inch telescope
- big man
- · Replies 3 ·
Graduate Locacal coordinate system in GR observed?
- hurk4
- · Replies 12 ·
Undergrad IAU 2006 definition of a planet: Pluto reclassified as dwarf planet
- Ouabache
- · Replies 7 ·
Undergrad Brightness of Mars as observed from earth
- lebbo
- · Replies 4 ·
High School How can stars burn without oxygen in space?
- MRCHEM
- · Replies 5 ·
Undergrad The moon moves in a near-circular orbit around earth
- lebbo
- · Replies 2 ·