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 Calculating Gravitational Energy
- Bravodhan
- · Replies 5 ·
Graduate Position angle of Moon's bright limb (formula)
- JeffOCA
- · Replies 5 ·
Graduate Steinhardt's crit of inflation (PIRSA video)
- marcus
- · Replies 21 ·
Graduate How does the jetstream of particles manage to escape from the blackhole?
- mdmaaz
- · Replies 12 ·
Undergrad Black Holes Schwarzschild radius
- Cbray
- · Replies 7 ·
High School Some questions about the Universe and its expansion.
- JerryClower
- · Replies 10 ·
Undergrad Dark energy - Expansion of the universe
- teddd
- · Replies 10 ·
Graduate Why aren't the <v^2> and <vr^2> curves different in my Hernquist model?
- LordV
- · Replies 1 ·
Graduate Black holes: zero volume and infinite density
- lovenugget
- · Replies 6 ·
Graduate Do sound vibrations from plate tectonics (earthquakes) attract asteroids?
- dreamerregina
- · Replies 2 ·
Graduate 12 min orbit white dwarfs found Best target for gravitational waves
- MTd2
- · Replies 4 ·
Stargazing Why do Blanco telescope blue filters transmit blue light?
- randa177
- · Replies 8 ·
Is the JWST Doomed? Scientists Speak Out Against Budget Cuts
- Tanelorn
- · Replies 1 ·
Undergrad Calculating gravitational acceleration between Earth and Sun for N-body simulation
- braindeaduser
- · Replies 6 ·
Graduate Into what shape does an orbiting sphere get distorted by tidal forces?
- Paulibus
- · Replies 4 ·
Graduate How Do Thermodynamics and Branes Influence the Universe's Origin?
- alex_j
- · Replies 3 ·
Graduate How does the universe handle paradoxes caused by time travel?
- soryy708
- · Replies 2 ·
Graduate Information on first planets formed in the universe
- Cosmo Novice
- · Replies 1 ·
Undergrad Where Can I Find Accurate Data for Simulating Solar System Orbits in Java?
- trelek2
- · Replies 4 ·
Graduate Electro magnetic craft levitation at earths magnetic pole possible?
- siiix
- · Replies 1 ·
Graduate Missing matter found by Monash student.
- scvblwxq
- · Replies 19 ·
High School How would you steer a spacecraft?
- Germanunkol
- · Replies 22 ·
Graduate CMBR anisotropies and constraints on universal rotation
- Lino
- · Replies 4 ·
Graduate Find Orbital Elements given Orbital State Vectors
- FireStorm000
- · Replies 7 ·
Graduate Physical meaning of the Gauss-Bonnet term in cosmology
- anuradha
- · Replies 2 ·
Graduate Can a new Big Bang arise from the energy of a dying universe?
- Nernico
- · Replies 58 ·
Undergrad The star Betelgeuse going supernova soon?
- Glennage
- · Replies 35 ·
Graduate How accurate are simple models of the solar system?
- Jack21222
- · Replies 13 ·
Graduate Magnetic Fields on Sudarsky Class II Gas Giants
- MattRob
- · Replies 1 ·
High School Interested in looking at the night sky
- Ironside
- · Replies 4 ·
Graduate Correct Physics for Fictional World
- MattRob
- · Replies 3 ·
Graduate How confident are we of the neutrino CMB energy density?
- BillSaltLake
- · Replies 4 ·
Undergrad Are we at the center of the universe and whats at the edge?
- YoungDreamer
- · Replies 27 ·
Undergrad What Determines the Size and Growth of a Black Hole?
- chippy!
- · Replies 6 ·
Graduate Collisional Astrophysics Models for Computer Scientists
- carltropper
- · Replies 2 ·
Graduate What Is Beyond The Observable Universe?
- Silverbackman
- · Replies 378 ·
Undergrad Why is the edge of the universe the place to look for the oldest stars?
- kilzok
- · Replies 21 ·
In Big Bang Theory (the show) what are their jobs?Serious
- maverick_starstrider
- · Replies 21 ·
Graduate What does a black hole look like from behind?
- Majo18
- · Replies 2 ·
Graduate Lunar solstice when the Moon's Equator crosses the Zero Plane of the Earth
- Philosophaie
- · Replies 1 ·
Potential Cancellation of the JWST
- SpecialKM
- · Replies 3 ·
Undergrad Objects in orbit are weightless?
- Whateverworks
- · Replies 9 ·
Graduate If somehow a supernova will be redirected to 30, 45, 60, 80, 90
- the6thmesseng
- · Replies 6 ·
Graduate Understanding Singularity: Zero Mass, Infinite Density
- YoungDreamer
- · Replies 3 ·
Graduate Quantum mechanics and black holes
- mikef20000
- · Replies 25 ·
Graduate Magnetic bubbles at the edge of the solar system and CMB
- zonde
- · Replies 21 ·
High School How Does Gravity Influence the Movements of Planets and Moons?
- Redi
- · Replies 3 ·
Best location for stars with naked eye
- blarznik
- · Replies 4 ·
Undergrad Is Iron the Ultimate Killer of Stars?
- vkash
- · Replies 13 ·
Graduate Elliptical Orbits (Using Newton's Model)
- stevmg
- · Replies 6 ·
Undergrad How Is Andromeda Approaching If Space Is Expanding?
- PlayUK
- · Replies 7 ·
Graduate What Form Did Matter and Antimatter Take During Annihilation After the Big Bang?
- Deepak247
- · Replies 5 ·
Graduate Is a Grand Unifying Theory Possible in an Evolving Universe?
- luigidopobici
- · Replies 7 ·
Graduate Hello PF.I would like to get your view on the plausible scenario
- Whateverworks
- · Replies 9 ·
Graduate Did early universe temperature differences persist through expansion?
- bkelly
- · Replies 23 ·
Undergrad Is the Mass of the Universe Accurately Represented in Astronomy Magazine?
- jimjohnson
- · Replies 4 ·
Graduate Spherical harmonic gravity model of asteroid 433 Eros coefficients increasing unexpectedly
- AdityaNanda
- · Replies 4 ·
Graduate Intergal result and quantum cosmology
- skydivephil
- · Replies 1 ·
Graduate Quantum mechanics and General Relativity overlap
- daveian
- · Replies 3 ·
Graduate How Do Acoustics in Space Affect Communication with Other Civilizations?
- stever19
- · Replies 7 ·
Stargazing How Do Telescopes Show Us Distant Objects in Space?
- minhas
- · Replies 6 ·
Graduate Can measurements of red shift be affected by the shape of spacetime?
- Tanelorn
- · Replies 18 ·
Undergrad Does dark energy strength increase with distance between objects?
- Cbray
- · Replies 11 ·
Undergrad NASA Space Shuttle Launches iPhone to Test Radiation Effects
- Sakha
- · Replies 3 ·
Undergrad Researching to Become a Theoretical Astrophysicist
- Cbray
- · Replies 1 ·
Graduate What Was the Mass of the Universe Immediately After the Big Bang?
- nearc
- · Replies 4 ·
Undergrad What is the ratio of hydrogen to helium in the Sun?
- shirin
- · Replies 3 ·
Graduate When a protostar stops contraction
- shirin
- · Replies 3 ·
Graduate Most Distant Quasar a Theory Problem?
- Dotini
- · Replies 19 ·
Graduate Solar sail using radioactive decay
- udtsith
- · Replies 26 ·
Graduate An upper limit to the size of black holes?
- bkelly
- · Replies 1 ·
Undergrad Could a Swallowed Moon Explain Uranus's Tilt and Magnetic Field?
- YoungDreamer
- · Replies 4 ·
Undergrad Why does the permeability of free space invoke pi?
- connorb1542
- · Replies 22 ·
Graduate Mass distribution inside the event horizon
- PaulMurphy
- · Replies 3 ·
Undergrad How does relativity relate to universe expansion and Einstein's cosmological constant?
- phys lover199
- · Replies 1 ·
Graduate An age of the Universe around 20 billion years
- yheyman
- · Replies 3 ·
Graduate Primordial Black Holes: Could Spacetime Form BHs?
- PaulMurphy
- · Replies 1 ·
Undergrad Is the Universe Really Cyclic and Set to Repeat?
- byron178
- · Replies 15 ·
Graduate You should be shot for asking: how does matter move faster than light?
- marcus
- · Replies 4 ·
Graduate What existed before the quantum vacuum if it preceded the Big Bang?
- Nernico
- · Replies 8 ·
High School Can an asteroid be permanently captured into Earth's orbit like the moon?
- TitanRZ
- · Replies 16 ·
Graduate Top 10 Questions on Leonard Susskind's "The Black Hole War
- PaulMurphy
- · Replies 11 ·
Undergrad What causes the universe to expand?
- S_McLachlan
- · Replies 8 ·
High School Landing a Spacecraft: Understanding Gravity in Space
- emma149
- · Replies 5 ·
Graduate Can black holes form without gravity in the early universe?
- dlevanchuk
- · Replies 6 ·
Graduate YSBSFA: how did our matter get here ahead of the light?
- marcus
- · Replies 3 ·
Graduate Understanding rotation of spiral galaxies
- eaclou
- · Replies 2 ·
Undergrad Space Elevators and Other Alternatives
- Nano-Passion
- · Replies 71 ·
Graduate Control Systems, State space to Transfer Function
- k87
- · Replies 1 ·
Undergrad How to overcome Mars' CO2 atmosphere and radiation for terraforming
- Nikitin
- · Replies 80 ·
Graduate Helium Abundance in ISM of Galaxies: Best-Estimate Value
- vladivostok
- · Replies 1 ·
Graduate How is the 15.5 billion year age of the universe determined?
- eighteyes
- · Replies 7 ·
Undergrad Star formation: stellar output, HII fraction, and supernovae
- Telephone
- · Replies 2 ·
Graduate How could distant objects form at similar times after the Big Bang?
- TheRealUFOMan
- · Replies 8 ·
Graduate Initial conditions for a halo orbit
- Deadstar
- · Replies 1 ·
Graduate Variations in the fine structure constant
- enotstrebor
- · Replies 2 ·
Graduate ? about Steven Weinberg's view on theroretical prejudices
- phinds
- · Replies 13 ·
Space travel on TV infuriates me
- Pengwuino
- · Replies 3 ·
Graduate Does the Universe Rotate and Does it Have an Axis?
- utek1
- · Replies 92 ·
Graduate What does homogeneity mean (in the cosmological context)?
- Lino
- · Replies 13 ·