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 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 ·
Graduate Is Too Much Physics Bad For Astronomy?
- ZapperZ
- · Replies 5 ·
Graduate Details on the galaxy crash in our future
- marcus
- · Replies 1 ·
Undergrad Is Pluto's Axis of Rotation Almost Perpendicular to Its Orbit?
- DaveC426913
- · Replies 3 ·
High School Signal Transmission from Mars to Earth
- NeoScience
- · Replies 4 ·
Stargazing Building a telescope for a physics project
- holliee
- · Replies 2 ·
Graduate Which Statements about Cold and Hot Dark Matter are Incorrect?
- kingwinner
- · Replies 4 ·
Undergrad Brightest supernova ever observed
- marcus
- · Replies 1 ·
Graduate What is the true definition of proper distance in cosmology?
- pervect
- · Replies 16 ·
Graduate Cosmology: Is Universe Finite or Unbounded?
- da_willem
- · Replies 2 ·
Graduate Could external force cause cosmic expansion instead of dark energy?
- ukmicky
- · Replies 4 ·
High School Universe Expansion: How Fast Is It?
- Chris_Gottschal
- · Replies 2 ·
Graduate How can tidal friction on Earth affect the Moon?
- smithpa9
- · Replies 5 ·
Graduate What Are the Possible Changes in the Fine Structure Constant in the Past?
- talksabcd
- · Replies 3 ·
Graduate Bill Thomson, Harold Jeffreys and Dark Stuff
- oldman
- · Replies 45 ·
High School What is the term for light from the dark part of the moon facing earth
- bassplayer142
- · Replies 13 ·
Graduate Why doesn't gravity slow the universe's expansion?
- ChristianGolfer
- · Replies 34 ·
Undergrad Dark Matter: Info and Math Equations
- apope
- · Replies 3 ·
Graduate Can I Ignite a Star with 1.1 kg of Mass?
- tony873004
- · Replies 6 ·
Graduate How to Calculate the Readout Noise of a CCD?
- r-dizzel
- · Replies 1 ·
Most earthlike exoplanet yet (ESO team 23 April)
- marcus
- · Replies 17 ·
Undergrad Atmospheric Refraction vs Height
- natski
- · Replies 4 ·
Graduate Where Did the Energy from Early Universe Radiation Go?
- aludwig
- · Replies 7 ·
Graduate What is the redshift of the end of the inflationary era?
- George Jones
- · Replies 10 ·
Graduate Could a Spinning Star Defy Gravitational Collapse?
- MonstersFromTheId
- · Replies 6 ·
Graduate Why do we need gravitons if gravity curves spacetime without them?
- Nen
- · Replies 9 ·
Graduate How much of a quasar's redshift comes from gravitational redshift?
- talksabcd
- · Replies 10 ·
Graduate Why the universe is not a black hole (merged)
- Roy Edmundson
- · Replies 9 ·
Graduate Is Self Creation Cosmology a Viable Alternative to the Standard Model?
- Garth
- · Replies 127 ·
Crab nebula rippling
- OSalcido
- · Replies 1 ·
Graduate What astrophysical processes polarize light and how?
- RJ Emery
- · Replies 3 ·
Wikisky.org - beautiful views of the universe
- OSalcido
- · Replies 2 ·
High School Writing a 5-minute speech on estimating the size of the universe
- Firepanda
- · Replies 7 ·
What is dark matter?
- solaisenberg
- · Replies 7 ·
Graduate Where is the Cosmological Event Horizon in the LCDM model?
- marcus
- · Replies 4 ·
Graduate If energy cannot be destroyed, how can everything eventually die?
- Zenparticle
- · Replies 7 ·
Graduate What expands if there's no rubber?
- marcus
- · Replies 12 ·
Graduate If two white-dwarf stars combined together,there will be supernova?which type?-
- magnetar
- · Replies 7 ·
High School Math prerequisites and resources for learning astrophysics
- Red Anvil
- · Replies 15 ·
Undergrad Could simulations using known laws reveal undiscovered physics?
- bassplayer142
- · Replies 4 ·
How many galaxies have been observed?
- Glynis
- · Replies 10 ·
Undergrad What happens if a ship at 0.1c hits space debris or a probe?
- Fletcher
- · Replies 10 ·
Graduate Can you detect dark energy and dark matter within a single galaxy?
- wolram
- · Replies 17 ·
Graduate How does the Sun's fusion process work and what's between its core and surface?
- Poita
- · Replies 8 ·
Graduate Atmospheric Absorption of Starlight
- sderamus
- · Replies 1 ·
Graduate How can we see the cosmic background radiation?
- FizX
- · Replies 5 ·
High School Origin of Radio Waves: An Explanation
- Glynis
- · Replies 1 ·
Graduate Does the Coupling Between Space and Matter Affect the Expansion of Our Universe?
- wolram
- · Replies 3 ·
High School Why Did NASA Rename Its Astrophysics Division to Universe?
- marcus
- · Replies 1 ·
Graduate Ekpyrotic model explanation of the big bang
- SuperStringboy
- · Replies 4 ·
Graduate Can dark energy be explained by superconductors?
- wolram
- · Replies 1 ·
Graduate Humans can maybe create a universe
- fournier17
- · Replies 22 ·
High School Why is a Comet More Dangerous Than an Asteroid?
- Nuklear
- · Replies 15 ·
Undergrad Inflation (The evolution of the Universe)
- Bart
- · Replies 12 ·
Undergrad OK. So was the Big Bang the beginning or not?
- FeynmanMH42
- · Replies 16 ·
Graduate Sad disconnect at Cosmic Variance blog-how not to discuss
- marcus
- · Replies 9 ·
Graduate Why Is LCDM Preferred Over VSL in Modern Cosmology?
- fasterthanjoao
- · Replies 3 ·
High School Why should gas giants like Jupiter count as planets without solid surfaces?
- Nuklear
- · Replies 14 ·
Sun photos from Skyway Bridge September 2005 with unusual features
- Mario4272
- · Replies 1 ·
Graduate Can naked singularity actually move the space craft in PAST?
- Huma waseem
- · Replies 12 ·
High School Hexagon on Saturn: NASA Investigates
- ukmicky
- · Replies 1 ·
Undergrad Why was Roemer's speed of light measurement off by 80,000 km/s?
- Cane_Toad
- · Replies 6 ·
Graduate Estimating the ratio of flux of sunlight to moonlight (at full moon)
- cragwolf
- · Replies 2 ·
Graduate Velocity of rotation at the edge of the Galaxies
- talksabcd
- · Replies 5 ·
Undergrad Absolute Magnitudes for Cepheids
- sailof
- · Replies 2 ·
Graduate Where Did the Electrons Come From in Big Bang Nucleosynthesis?
- sruthisupriya
- · Replies 4 ·
Graduate Is Empty Space Beyond the Universe Influencing Its Expansion?
- bogie
- · Replies 36 ·
Chris Hillman plaintalk summary of today's GPB announcement
- marcus
- · Replies 1 ·
Graduate Radiative equilibrium in near-Earth space
- nugae
- · Replies 2 ·
High School Why does a comet lose its tail permanently?
- pixel01
- · Replies 1 ·
Graduate How Did Quantum Fluctuations Initiate the Big Bang?
- FeynmanMH42
- · Replies 7 ·
Graduate Are there newer theories of spiral galaxy formation beyond shock waves and density waves?
- wolram
- · Replies 3 ·
Graduate Where are the Rules of the Universe Stored?
- grahamc
- · Replies 45 ·
Undergrad Can dark matter clump together to form a star?
- ukmicky
- · Replies 10 ·
Graduate Why Is Heat Distribution Unequal in the Expanding Universe?
- csrichie
- · Replies 3 ·
Orange light that appeared and disappeared in the sky
- Chris_Gottschal
- · Replies 4 ·
Graduate What is the Ultimate Source of Energy in the Universe?
- ReggieB
- · Replies 37 ·
Graduate Further looks bigger beyond z = 1.6
- marcus
- · Replies 6 ·
Graduate Why does M87's jet appear to move faster than light?
- RJ Emery
- · Replies 1 ·
Graduate Massive neutron star rules out exotic matter
- wolram
- · Replies 1 ·
Undergrad Can Mars Effect the Asteroid Belt?
- Giuseppe Mayart
- · Replies 1 ·
Graduate Could gravity's strength also require denisty as an alternative to MOND
- ensabah6
- · Replies 1 ·
Graduate Calculating the redshift at which radiation energy density equaled mass density
- yijiao
- · Replies 4 ·
Graduate Imaginary engine powered by dark energy with dark matter governor
- wolram
- · Replies 2 ·