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 Thick-Skinned Gravastars Vie to Replace Black Holes, in Theory
- brum
- · Replies 3 ·
Graduate What stops a star from fusing all its fuel at once?
- only_theory
- · Replies 16 ·
Graduate Does acceleration make distant observers see objects slow down like near a black hole?
- Sheneron
- · Replies 12 ·
Graduate Does Flat Space Exist in the Context of General Relativity?
- yuanwei
- · Replies 4 ·
Graduate I don't like Dark Matter and Dark Energy
- Illuminaughty
- · Replies 35 ·
Graduate Calculating Celestial Coordinates
- science.girl
- · Replies 5 ·
Undergrad Distance to stars from my house using the parallax technique?
- Stratosphere
- · Replies 5 ·
Graduate Inferring center of mass distance from velocity and acceleration in an orbit
- DiamondGeezer
- · Replies 95 ·
High School Do Planets Orbit Closer to the Sun Over Time?
- mikejr82
- · Replies 1 ·
Graduate How is the Proton to Neutron Ratio Calculated After the Big Bang?
- electerr
- · Replies 6 ·
Graduate Can Black Holes Bend Light and Act as a Time Machine?
- PhantomOeo
- · Replies 14 ·
Graduate Slowing time or expanding space?
- skypunter
- · Replies 1 ·
Graduate Evaluating distance of far objects in space
- philhar
- · Replies 3 ·
Undergrad The origins of universe and development
- Dex
- · Replies 2 ·
Undergrad What Gases Are Present in Dwarf Planets and Kuiper Belt Objects?
- mikejr82
- · Replies 7 ·
High School Distance analogy - am I being accurate?
- leogarcia61
- · Replies 4 ·
Graduate Can Non-Cosmological Redshifts Explain Anomalies in Galaxy Interactions?
- turbo
- · Replies 71 ·
Graduate Seeing Back to the Big Bang: Is it Possible?
- ChrisXenon
- · Replies 3 ·
High School Size of the Universe is 13.7 billion light years?
- Beaudoin
- · Replies 14 ·
Graduate Why is the curvature term in Friedmann equations restricted to k = 0, -1, +1?
- $id
- · Replies 2 ·
Graduate Do the cosmological expansion affect binding systems
- dimilion
- · Replies 2 ·
Graduate Misconceptions about expanding space
- nutgeb
- · Replies 12 ·
High School How do you figure out which zodiac constellation the sun crosses in a given month?
- Cyrus80772
- · Replies 20 ·
Graduate Effective weight of a star's layers
- Nabeshin
- · Replies 12 ·
Undergrad CAMB Output File: TT Power Spectrum (C_l) Columns
- Angelos K
- · Replies 3 ·
Graduate Superluminal Jets: 6c Speeds Detected!
- Zman
- · Replies 1 ·
Undergrad EMwave in space and copper wire.
- jainabhs
- · Replies 2 ·
Graduate What happens to a 0.7 solar mass star when it comes off the main sequence?
- Maria76
- · Replies 7 ·
Graduate Alien Maps of an Ocean-Bearing World
- marcus
- · Replies 1 ·
CD player as a gyroscope in space
- qntty
- · Replies 2 ·
High School Outer space where there was no gravity
- cragar
- · Replies 10 ·
Undergrad Star Calculator (Excel spreadsheet)
- HerrÅberg
- · Replies 2 ·
High School Why do heavenly bodies rotate and what causes this rotation?
- PalashD
- · Replies 9 ·
Graduate How Long Does an Interstellar Cloud Take to Contract?
- knhlove
- · Replies 1 ·
Graduate Is the universe expanding or accelerating?
- Sundance
- · Replies 101 ·
Graduate Can a 3-Space Be Isotropic About Two Distinct Points Without Being Homogeneous?
- lark
- · Replies 3 ·
High School Location of the Asteroid Belt between Mars and Jupiter
- Philosophaie
- · Replies 7 ·
Graduate Why Does the Expanding Universe Cause Red Shift?
- ChrisXenon
- · Replies 7 ·
Graduate Gaining Orbital Energy from Sun's Gravity-Assist Flyby
- Jorrie
- · Replies 10 ·
Graduate The maximum mass of white dwarf star
- feynmann
- · Replies 6 ·
Graduate How Many Elements Formed from Primal Plasma?
- wolram
- · Replies 4 ·
Graduate Explanation on how inflation solves the horizon and flatness problem
- trv
- · Replies 2 ·
Graduate Why are the primordial fluctuations called scale invariant?
- Allday
- · Replies 5 ·
Undergrad Absolute magnitude of a 60W light bulb compared to the Sun
- wyse
- · Replies 9 ·
Graduate Virtual pair production - black holes
- geniusprahar_21
- · Replies 7 ·
Graduate lowest scatter Hubble diagrams ever published (Bailey et al)
- marcus
- · Replies 1 ·
Undergrad Did the early sun's greater mass make it large enough to engulf Earth's orbit?
- LostInSpaceTime
- · Replies 3 ·
Graduate Is DNA Production a Constant in the Life Cycle of the Universe?
- Belzy
- · Replies 8 ·
Graduate Do Galaxies and the CMB Share the Same Reference Frame?
- neopolitan
- · Replies 24 ·
High School Gravity in the Middle of a Planet: Puzzling Questions
- cosmicpencil
- · Replies 3 ·
Undergrad Does the Earth-Moon system work like a binary with tidal forces?
- raknath
- · Replies 24 ·
Undergrad Are multiple universes and higher dimensions the same thing?
- thepopasmurf
- · Replies 1 ·
Stargazing Cleaning Eyepieces - What's the Best Method?
- Sheneron
- · Replies 10 ·
Undergrad The Odds of Life in the Universe - What Are Your Thoughts?
- cosmicpencil
- · Replies 15 ·
Graduate How is Hawking Radiation Related to a Black Hole's Mass and Time of Dissipation?
- Synchrotron
- · Replies 3 ·
Graduate Determining the Best Wavelength for Darwin's Space Mission
- wyse
- · Replies 3 ·
Graduate What is the force of the cosmological constant?
- Ranku
- · Replies 12 ·
Graduate How display a mollview projection of CAMB output fits file ?
- fab13
- · Replies 1 ·
Undergrad Could the shuttle land with Hubble?
- squidsoft
- · Replies 9 ·
High School Is Mars Really Approaching Close to Earth on August 27th?
- GetPhysical
- · Replies 4 ·
Undergrad Can elevons and rudders effectively steer spacecraft in the vacuum of space?
- bluej774
- · Replies 4 ·
Graduate Can we determine the rotation speed of a black hole?
- cosmicpencil
- · Replies 5 ·
Graduate How are Supernovae Ia and Dark Energy Related?
- pi.rootpi
- · Replies 2 ·
Graduate Formation of Relativistic Jets from Black Holes
- Oscar Wilde
- · Replies 1 ·
Graduate How can a closed 4D manifold accommodate an expanding universe?
- Schlofster
- · Replies 13 ·
High School What makes an asteroid an asteroid and not a comet
- raknath
- · Replies 8 ·
Graduate Best model to explain expansion of universe is needed
- eha
- · Replies 6 ·
Graduate Assigning Contributions of Dark Energy to the Cosmos
- RoKo
- · Replies 7 ·
Undergrad What are the actual dimensions of the Horsehead nebula?
- Maria76
- · Replies 1 ·
Graduate What is Equation of state for the Dark Matter?
- Dmitry67
- · Replies 9 ·
Graduate The new Hubble rate estimate of 74 means a new critical density.
- marcus
- · Replies 10 ·
Graduate Why does the Moon orbit Earth when the Sun's gravitational pull is stronger?
- zarmewa
- · Replies 4 ·
High School Is the Spin of Earth Constant Throughout the Year?
- Mahbod|Druid
- · Replies 4 ·
Graduate How can it be that gravity can bend time and slow it down
- cosmicpencil
- · Replies 8 ·
Graduate What are the differences between rotating and non-rotating black holes?
- Mr. Paradox
- · Replies 3 ·
Undergrad How can distant galaxies recede faster than light if space itself is expanding?
- cosmicpencil
- · Replies 2 ·
Graduate Is it Possible to Escape a Black Hole Using a Spaceship and Hawking Radiation?
- ACG
- · Replies 18 ·
Graduate Is Our Universe the Creation of Intelligent Aliens?
- pavi_elex
- · Replies 13 ·
Graduate How does the equation-of-state depend on the Quintessence potential?
- Amanheis
- · Replies 1 ·
Graduate Is gravity driving the expansion of the universe? If so
- NWH
- · Replies 3 ·
Graduate Is Cosmic Radiation Accounting for Missing Matter and Energy in the Universe?
- OB 50
- · Replies 8 ·
Graduate Schwarzschild radius and black hole entropy
- hkhandrika
- · Replies 10 ·
Undergrad Is there really a black hole at the center of the Milky Way?
- klite
- · Replies 1 ·
Undergrad Works of Riemann related to Astronomy that I can understand?
- benorin
- · Replies 3 ·
Undergrad Does Star Evolution Always Lead to Expansion?
- Maria76
- · Replies 1 ·
Graduate What is Wheeler's participatory principle and how does it apply to modern cosmology?
- Belzy
- · Replies 1 ·
Graduate What's the real story behind recent dark matter media coverage?
- nicksauce
- · Replies 11 ·
Graduate Moving an asteroid into Earth orbit
- Count Iblis
- · Replies 8 ·
Graduate Does dark flow provide evidence for another universe?
- buffordboy23
- · Replies 4 ·
Graduate What were the necessary conditions for the Big Bang?
- gabrielh
- · Replies 7 ·
High School Giant blob of gas detected in early universe
- Ivan Seeking
- · Replies 8 ·
PG&E signs deal for space-based solar power
- Ivan Seeking
- · Replies 8 ·
Graduate What Is Containing Our Universe?
- Sorry!
- · Replies 4 ·
Undergrad Why are the orbits elliptical in shape?
- yalgaar
- · Replies 20 ·
Undergrad How much lighter do I weigh at noon than I do at dawn?
- thenewmans
- · Replies 9 ·
Graduate Why is the Big Bang force not studied as much as gravity in cosmology?
- youngkiwi
- · Replies 8 ·
Graduate What Was the Force Holding Matter Together Before the Big Bang?
- XanPaul
- · Replies 35 ·
Graduate If objects are accelerating, are we measuring the systems getting smaller?
- NWH
- · Replies 5 ·
High School Can we calculate when Earth will spiral into the sun?
- learningisfun
- · Replies 19 ·
Graduate Accelerating universe, decreasing hubble constant
- Ranku
- · Replies 8 ·