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 Calculate time (or fraction of orb. period) of sat. in umbra
- thor36
- · Replies 2 ·
What topics are covered in the University of Arizona's Cosmology Video Lectures?
- Greg Bernhardt
- · Replies 6 ·
Graduate Multiverse and Eternal Inflation Disproved?
- Thomas Moore
- · Replies 8 ·
Graduate Entanglement as the fabric of space-time?
- sanpkl
- · Replies 2 ·
Asteroid 2004 BL86 and its small moon
- Dotini
- · Replies 7 ·
High School Why do natural Moons revolve around planets?
- officialmanojsh
- · Replies 16 ·
What is the A Grand Tour of the Universe video series about?
- Greg Bernhardt
- · Replies 6 ·
Graduate How to measure curvature of 3-sphere from inside its surface
- gulfcoastfella
- · Replies 4 ·
Graduate The initial mass function (IMF) of main-sequence stars,
- bbc
- · Replies 16 ·
Graduate Is all the space there is here now or is space being created
- CaptDude
- · Replies 4 ·
High School Can We Use Silicon Oxide Bags to Fly to the Moon?
- mark!
- · Replies 8 ·
Graduate Gravitational Collapse: How Long Does it Take?
- Ott Rovgeisha
- · Replies 25 ·
Graduate You think there's a multiverse? Get real
- Garth
- · Replies 71 ·
High School What Would We See When Traveling to a Star at Light Speed?
- NoamRiahi
- · Replies 6 ·
Graduate What Fundamental Force Played a Key Role in the Big Bang?
- Wes Tausend
- · Replies 21 ·
A couple of new pix -- M42 and Eta Carina
- davenn
- · Replies 22 ·
Graduate What happens if you travel beyond the observable universe?
- ScientificMind
- · Replies 10 ·
Undergrad Astrophysics Books by Frank Shu | Student Guide
- Kostas Tzim
- · Replies 4 ·
Undergrad Heat and Magnetism: How Does the Sun Maintain Its Magnetism?
- H012
- · Replies 2 ·
Graduate In depth Mars flight trajectory studies
- Taylor Grubbs
- · Replies 5 ·
Graduate Can a singularity expand in volume?
- Al-Aqsa Akbar
- · Replies 5 ·
Graduate How Does the CMB Power Spectrum Relate to Angular Scales?
- ChrisVer
- · Replies 3 ·
Graduate Did space time be created at the Big Bang?
- Quds Akbar
- · Replies 3 ·
Graduate What is the Jeans Anomaly and How Does it Relate to the Birth of a Star?
- Kostas Tzim
- · Replies 2 ·
Graduate Was the announcement that BICEP2 has detected Inflation Gravity Waves premature?
- Garth
- · Replies 15 ·
Graduate How to calculate the mass of a star using redshift?
- LachyP
- · Replies 7 ·
Undergrad Is the Big Bang Theory Just a Pseudo-Issue?
- Priyank
- · Replies 12 ·
Graduate Is Nature Symmetric? A Deeper Look
- GiuseppeR7
- · Replies 9 ·
Graduate Is my reasoning correct? Energy "before" the big bang?
- toothpaste666
- · Replies 10 ·
Undergrad Scenarios for end of the universe
- toothpaste666
- · Replies 3 ·
Graduate Why was the flat, no Lambda Universe previously favoured?
- center o bass
- · Replies 4 ·
High School Gravity -- Does gravity depends on atmosphere?
- san D
- · Replies 31 ·
Graduate Heavy water mismatch between comet 67P and Earth's oceans
- HowardVAgnew
- · Replies 17 ·
Undergrad Space Hazards on ISS: How Much Is at Risk?
- GTOM
- · Replies 9 ·
High School Dawn distance to Ceres ≈ distance to moon
- marcus
- · Replies 41 ·
Graduate CMB dipole anisotropies- we are moving towards cmb?
- ChrisVer
- · Replies 11 ·
Graduate Hypothetical Galactic Navigation System Question
- Physt
- · Replies 2 ·
Graduate Assumptions in dark-energy density parameter measurement
- center o bass
- · Replies 3 ·
Graduate Giant ring system around exoplanet discovered
- mfb
- · Replies 1 ·
Undergrad What would Kessler Syndrome really look like?
- DamonX
- · Replies 5 ·
Graduate Natural Spectrum of the Universe?
- Physt
- · Replies 12 ·
Space Burial: A Futuristic Dream or a Possible Reality?
- iDimension
- · Replies 23 ·
Graduate Microbial mats traced in Mars sediment? Noffke's hypothesis
- marcus
- · Replies 17 ·
Graduate First cosmology computer simulations
- TEFLing
- · Replies 7 ·
Can Radio Telescopes Capture Detailed Images of Asteroids and Their Moons?
- Andy Resnick
- · Replies 7 ·
Graduate Comets' High Deuterium-to-Hydrogen Ratios Explained
- TEFLing
- · Replies 27 ·
Top Sky Viewing Apps for iPhone: A Comparison
- Greg Bernhardt
- · Replies 28 ·
Graduate Does the universe expand uniformly and do closer galaxies accelerate differently?
- orionis
- · Replies 18 ·
Graduate Confused about binary star systems?
- 21joanna12
- · Replies 6 ·
Graduate What Makes the Present Moment Special in an Expanding Universe?
- TEFLing
- · Replies 28 ·
Graduate Is Space-Time Curvature Just a Force Field?
- Euclid Areti
- · Replies 23 ·
Will Dawn successfully enter orbit around Ceres?
- marcus
- · Replies 1 ·
Undergrad Do Pulsars Really Produce Sounds or Are They Just Radio Wave Representations?
- subzero0137
- · Replies 10 ·
Graduate Event Horizon in a closed, matter (dust) dominated universe
- Heisenberg1993
- · Replies 1 ·
Undergrad What is the definition of disc scalelength?
- PCB
- · Replies 6 ·
Graduate Pre big bang infinite cold inflation?
- zerozenones
- · Replies 9 ·
Graduate What Happens to Gravity When an Object Travels at the Speed of Light?
- hafiz ns
- · Replies 21 ·
Undergrad Diameter of Earth-like planet / gravitational force
- chris2112
- · Replies 6 ·
Graduate Thermalized components/virialized
- ChrisVer
- · Replies 3 ·
Graduate Most total e-folds from inflation
- chasrob
- · Replies 7 ·
Graduate Methods to find exoplanets more easily
- Gitirana
- · Replies 5 ·
Graduate How to determine the mass of a planet using redshift?
- avito009
- · Replies 4 ·
Undergrad How can you tell what kind of orbit a body will have?
- 21joanna12
- · Replies 5 ·
Graduate Can Weibel Instability Generate Cosmic Magnetic Fields?
- Dotini
- · Replies 5 ·
Graduate CMB Hemisphere of Evil: Planck Asymmetry Examined
- Chronos
- · Replies 16 ·
Graduate Modelling The Sun’s Magnetic Field
- JvanDyne
- · Replies 2 ·
Graduate What Makes a Black Hole a 'Hole' If It's a Point Mass?
- AdityaDev
- · Replies 2 ·
Undergrad What creates energy in a nova, supernova?
- King Solomon
- · Replies 3 ·
Graduate Stability of Orbital Resonance Ratios
- dragonfiremalus
- · Replies 5 ·
Cosmology/QED/Astrophysics Lectures: Ideas Welcome!
- Brian S.
- · Replies 2 ·
Graduate So what is your favourite theory for the beginning of the universe
- 11jdodds
- · Replies 10 ·
Graduate How massive do neutrinos need to be to account for all dark matter?
- edpell
- · Replies 24 ·
Graduate Integrated Sachs Wolfe Effect - redshifting?
- ChrisVer
- · Replies 1 ·
Graduate Does energy level determine the smallest region of spacetime that can be probed?
- Edward Wij
- · Replies 1 ·
Graduate Paradox on the Chandrasekhar Limit
- ubergewehr273
- · Replies 9 ·
Graduate Earth-Like Planets & Iron: Questions Answered
- Johninch
- · Replies 51 ·
Graduate Why aren't there any space tugs in use?
- Ganesh Ujwal
- · Replies 14 ·
Undergrad How did "Visible light" come into existence?
- Timelord88
- · Replies 8 ·
Graduate Is Dark Energy a Myth?
- wolram
- · Replies 17 ·
Stargazing How Can I Build a Telescope?
- Vphysics2013
- · Replies 13 ·
Where Can I Find Comet Lovejoy in the Sky Right Now?
- davenn
- · Replies 15 ·
High School Earth-Sun Distance: Perfect for Life?
- Star28
- · Replies 24 ·
Undergrad Image reduction and analysis software for windows
- PLuz
- · Replies 6 ·
Graduate Diapl - Difference Image Analysis Package
- yba
- · Replies 3 ·
Graduate Question about the Penrose process
- pbjsandwich
- · Replies 2 ·
Graduate Is it possible to understand inflation through Einstein?
- Stoney Pete
- · Replies 1 ·
Graduate Understand CMB Anisotropies & Interpret Figures
- ChrisVer
- · Replies 3 ·
Graduate CMB dipole anisotropies & Hubble's Law
- ChrisVer
- · Replies 10 ·
Undergrad Floating in space and angles of galaxies
- elusiveshame
- · Replies 12 ·
Graduate Making sense of distance and speed of expanding universe
- supernova88
- · Replies 12 ·
Graduate When can I use radiation pressure P = αT⁴ for stars in virial equilibrium?
- leonmate
- · Replies 1 ·
Graduate Anti-matter annihilation and the CMBR
- Herbascious J
- · Replies 7 ·
Graduate Size of the Observable universe at the Big Bang Singularity
- Drakkith
- · Replies 8 ·
Graduate I Simply Cannot Understand Olbers' Paradox -- Finite/Infinite Universe
- BHL 20
- · Replies 20 ·
Graduate Differential equation for motion within stars
- leonmate
- · Replies 6 ·
Graduate What happens in the center of mass of binary star system ?
- WallaceHS
- · Replies 9 ·
Graduate Is Time Quantized? | Scientific American
- CaptDude
- · Replies 2 ·
Graduate How to estimate/calculate stellar wind from a star?
- AotrsCommander
- · Replies 6 ·
Graduate How Does Motion Influence Wave Frequency in Doppler Shift?
- D_Laban
- · Replies 1 ·
Stargazing How Can I Build My Own Telescope Without a Tube?
- mishoz
- · Replies 2 ·