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 Arcsecond size of the Andromeda Galaxy
- Simfish
- · Replies 2 ·
Graduate Can True Zero Velocity Be Measured in Space?
- capri debris
- · Replies 17 ·
Graduate The Clumping of Dark Matter: A Question of Friction?
- skippy1729
- · Replies 4 ·
Graduate Inflation or normal space/time misunderstood?
- PaulS1950
- · Replies 23 ·
High School A strange informataion is ot realy
- the doctor
- · Replies 6 ·
Graduate Planck's Length and the Quantum Theory of Gravity
- PhanthomJay
- · Replies 2 ·
Graduate How can space be created faster than light during inflation?
- magnusrobot12
- · Replies 11 ·
Graduate Is there a place in space where there is no energy?
- cragar
- · Replies 6 ·
Undergrad Solutions for general astronomy 2 homework questions
- bob1230
- · Replies 1 ·
Graduate Black hole/Hawking radiation thought experiment
- marconius
- · Replies 1 ·
Graduate Why don't black holes disconnect themselves from the universe?
- Deepak Kapur
- · Replies 27 ·
Graduate When did the cosmic microwave background cool to 3 degrees?
- HarryWertM
- · Replies 6 ·
Graduate How does quasar feedback work?
- seto6
- · Replies 2 ·
Undergrad How is dark matter different from the 19th-century aether concept?
- ComfortNumb
- · Replies 7 ·
Undergrad Can the force of gravity from a Black Hole be escaped?
- rusher38
- · Replies 8 ·
Graduate Nuclear Decay Earth Sun Distance
- Saul
- · Replies 1 ·
Undergrad What are gravitational waves made of and what would happen if one hit Earth?
- Gravitons
- · Replies 12 ·
High School Is Evolution Considered Part of Cosmology?
- jaebaeli
- · Replies 7 ·
Graduate Is the three-body problem provably unsolvable?
- Isaac Newton
- · Replies 56 ·
Undergrad Planet Rotation: How Is It Possible?
- Godis1
- · Replies 4 ·
Graduate Traveling in an Expanding Universe
- JWINC
- · Replies 13 ·
Graduate What happens to an astronaut who enters the event horizon of a black hole?
- Energystrom
- · Replies 8 ·
Undergrad Astronomical data in an Ephemeris
- Philosophaie
- · Replies 11 ·
Graduate Could dark matter be linked to parallel universes?
- Numbertwo
- · Replies 1 ·
Graduate Does the Higgs field create both mass and gravity?
- Max Faust
- · Replies 22 ·
High School Questions About Space: Get Answers Here
- Misr
- · Replies 4 ·
High School What is the size of a black hole?
- Deepak Kapur
- · Replies 21 ·
Graduate How Does the Marcus Conjecture Connect CMB Energy Loss to Dark Energy?
- marcus
- · Replies 22 ·
Graduate Gravitational distortion of black holes
- Jon Richfield
- · Replies 16 ·
Graduate How to Calculate Energy and Power from Milky Way's Radio Emissions?
- mkitchen
- · Replies 1 ·
Graduate Gravitational redshift of light in containers at different gravitational fields
- MikeGomez
- · Replies 7 ·
Can anybody find a mistake in this Avatar photo?
- traciutaustin
- · Replies 24 ·
Cassini video of lightning on Saturn
- MarkitScience
- · Replies 5 ·
Graduate Violation of conservation of energy by expansion of the universe
- marthkiki
- · Replies 5 ·
Graduate Can a White Hole Exist as the Opposite of a Black Hole?
- IXI
- · Replies 19 ·
Undergrad Is gravitational redshift taken into account in Hubble's Law?
- m.w.lever
- · Replies 7 ·
Graduate Could cosmic acceleration be an illusion from changing constants?
- ItStartsWith1
- · Replies 17 ·
Graduate Is universe really observer dependent?
- Deepak Kapur
- · Replies 13 ·
Undergrad Being shot by a bullet in space. Damaging? Why/why not?
- rflxion
- · Replies 20 ·
Graduate Does energy convert to mass as often as mass converts to energy?
- jobyts
- · Replies 6 ·
High School Why are Stars Not Visible in Astronaut Photos?
- Farquezy
- · Replies 10 ·
Graduate Do virtual black holes inevitably form from the uncertainty principle?
- axemaster
- · Replies 4 ·
Graduate Why Do Star Systems and Galaxies Flatten in the 3rd Dimension?
- Dropout
- · Replies 2 ·
Graduate Universe as branching parallel worlds from probability at the Big Bang
- XurdeadX
- · Replies 1 ·
Graduate How are black holes linked to worm holes, or are they the same thing,
- Gravitons
- · Replies 6 ·
Undergrad How does one describe the energy of space to the public?
- solarblast
- · Replies 8 ·
Graduate Newbish questions (shape of the observable universe, blueshift, etc.)
- alpskomleko
- · Replies 6 ·
Was last night's fireball in the sky a meteor?
- EnumaElish
- · Replies 3 ·
Graduate Physics of creating a deliver-to-Earth-in-future signal
- nxr134
- · Replies 36 ·
Graduate How Can Two Tidally Locked Planets Coexist Without Catastrophic Repercussions?
- Helland
- · Replies 3 ·
Graduate Is the Earth's Thermal Output Constant Compared to Other Interstellar Cores?
- dirtyd33
- · Replies 3 ·
Graduate Hohmann Transfer: Maximum Radii Ratio
- sadiethebull
- · Replies 1 ·
Graduate Large-scale spatial geometry of the universe
- AWA
- · Replies 21 ·
Graduate A few different questions and concepts
- valdar
- · Replies 1 ·
Graduate 13.5 billion year age versus 93 billion due to spatial expansion?
- diagopod
- · Replies 12 ·
Graduate Where/when are we in a yo-yo universe?
- daveshorty
- · Replies 9 ·
Graduate Could Red Shift Be Influenced by Gravitational Effects Over Long Distances?
- walkerfx
- · Replies 33 ·
Graduate Calculate the redshift of a galaxy that is 650 Mpc away
- renmoresnow
- · Replies 10 ·
Graduate Dark matter as matter cooled to zero Kelvin
- JK0K
- · Replies 13 ·
Graduate Relativistic mass increase due to high temperatures inside stars?
- kahoon
- · Replies 2 ·
Graduate What could be beyond the boundaries of our seemingly infinite universe?
- Deepak Kapur
- · Replies 4 ·
Graduate Speed of Light and Size of the universe
- Praelly
- · Replies 4 ·
Graduate If spacetime is 3D, what dimension does it distort into?
- sreekant
- · Replies 15 ·
Graduate Is Chaotic Inflammatory Theory a valid theory in the field of physics?
- libbon
- · Replies 4 ·
High School Developed an interest in, Astronomy? Astrophysics?
- eveo
- · Replies 2 ·
Undergrad What causes gas and dust to form a star before gravity becomes significant?
- JayKo
- · Replies 16 ·
Graduate Why do quasars show little or no redshift?
- sanman
- · Replies 8 ·
Graduate Using Black Holes for FTL travel
- imadaman
- · Replies 9 ·
Undergrad Black hole structure and classification
- libbon
- · Replies 1 ·
Graduate What is the electron density of stars in their atmospheres?
- amalmirando
- · Replies 4 ·
Graduate How can you measure the mean density of a neutron star
- renmoresnow
- · Replies 2 ·
Undergrad Parabola for 18 aluminum mirror
- jixon
- · Replies 2 ·
Graduate Can an Atom Become a Black Hole?
- ALYAZAN
- · Replies 13 ·
Graduate Planetary orbits in a Binary Star system.
- ThomasEdison
- · Replies 4 ·
Graduate Query - could a comet impact create a wormhole?
- stany
- · Replies 12 ·
Graduate Universe expansion and hubble's law
- papa lazarou
- · Replies 6 ·
Graduate Can Photons Orbit a Black Hole?
- Medium9
- · Replies 4 ·
Undergrad Why is the Drake equation so famous?
- improsnipers
- · Replies 8 ·
Graduate What is the meaning of 'not perturbative accelerations' in astrodynamics?
- Rasalhague
- · Replies 9 ·
Graduate Lost energy of red shifted photons
- MikeGomez
- · Replies 4 ·
Graduate Fisheye Lens (alt/az) to Flat (RA/Dec)?
- solarblast
- · Replies 1 ·
Graduate Collapse of Dark Matter into Black Holes
- friend
- · Replies 7 ·
Graduate Dynamic Event Horizon: The Effects of Tidal Gravitational Forces on Black Holes
- qwe
- · Replies 4 ·
Graduate Why Do We Believe the Big Bang Contained All Matter and Energy in the Universe?
- Mazerakham
- · Replies 3 ·
Graduate Does the universe have a boundary?
- Mazerakham
- · Replies 8 ·
High School Can You Breathe in Space While Rockets Fire?
- sensor7
- · Replies 7 ·
Graduate Mark Whittaker says the dark matter cant cool
- BkBkBk
- · Replies 2 ·
Undergrad Canis Major dwarf galaxy *thought* to be our closest neighbor?
- GreatBigBore
- · Replies 17 ·
Graduate My First Post: conciousness, the brain, gravity, the universe. Connections?
- mattythewolf
- · Replies 2 ·
Undergrad What is the proportionality constant for the Sun's gravitational force?
- moonman239
- · Replies 3 ·
Graduate Can Matter Escape a Black Hole's Gravitational Pull Beyond the Event Horizon?
- ABHoT
- · Replies 3 ·
High School What Is Dark Matter?
- DaTario
- · Replies 54 ·
Graduate Dark Matter, Cluster Dynamics and The Bullet
- inflector
- · Replies 17 ·
Graduate Evidence of alien megastructures around stars
- ABHoT
- · Replies 3 ·
High School Moon's Lack of Atmos. vs Titan's Abundance
- danihel
- · Replies 2 ·
Graduate Current state of gravitational wave detection technology
- Ranku
- · Replies 3 ·
High School Measurements between sun and earth
- mullerfabien
- · Replies 5 ·
Graduate Time as a fractional spatial dimension
- dimensionless
- · Replies 11 ·
Graduate Some black holes may actually be Quark Stars
- rhody
- · Replies 8 ·
Graduate Our perception of Euclidean space
- madness
- · Replies 29 ·