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 What is the universe itself made of beyond its contents?
- WMan
- · Replies 7 ·
Identifying a classical mechanics book on orbital motion
- solarblast
- · Replies 2 ·
Graduate Is Our Universe Just a Balloon in an Infinite Matrix?
- megacal
- · Replies 2 ·
Graduate Explosion picture: most common mistake
- marcus
- · Replies 2 ·
Graduate Did a Higgs Boson trigger the big bang?
- Magnus Warhol
- · Replies 6 ·
Graduate How is the radius of the observable universe calculated?
- denism
- · Replies 32 ·
Undergrad Critical density in our expanding universe
- Positralino
- · Replies 4 ·
Graduate Could dark matter be invisible bound states of ordinary matter or ehm, aliens?
- Antti
- · Replies 1 ·
Graduate Can the universe have angular momentum in general relativity?
- Always curious
- · Replies 31 ·
Graduate Is the Sun's luminosity in specific filters greater than its overall luminosity?
- StarDweller
- · Replies 1 ·
Undergrad Venus Spinning Slower Than Thought
- Andre
- · Replies 25 ·
Graduate Eight steps to the understanding the CEH
- marcus
- · Replies 1 ·
Graduate Why is the Universe electrically neutral?
- lpetrich
- · Replies 2 ·
Graduate Observational evidence for gravitational wave structure, speed, and polarization
- SinghRP
- · Replies 6 ·
Undergrad What if time is not linear? Can it be experienced out of sequence?
- cdot
- · Replies 7 ·
Graduate Calculating Force and Energy Requirements for a Reactionless Drive in Space
- MIKESMIND
- · Replies 4 ·
Graduate Higgs & Inflaton: Does New Boson Discovery Change Anything?
- skydivephil
- · Replies 7 ·
Undergrad Is space really absolutely nothing?
- NeptuniumBOMB
- · Replies 20 ·
Graduate What Does Density Contrast in the Universe Mean in the Context of Chaplygin Gas?
- kptsilva
- · Replies 10 ·
Graduate What is absolute in this universe?
- Nikhilb
- · Replies 24 ·
Undergrad Distance time travels per second
- Pricey
- · Replies 3 ·
Undergrad Is there any cosmological research field concerning signal processing?
- uglybachelor
- · Replies 3 ·
Graduate The theory of Cosmological Relativity by Dr. Moshe Carmeli.
- kuartus4
- · Replies 7 ·
Undergrad Is Dark Flow Considered a Fringe Theory?
- Chaos' lil bro Order
- · Replies 4 ·
Graduate Finding when the Earth-Sun-Mars angle reaches 44.4 degrees
- xaz
- · Replies 1 ·
Undergrad How does one descibe a co-orbiting system?
- Lino
- · Replies 2 ·
Graduate Why an infinite time's arrow is impossible
- james.goetz
- · Replies 58 ·
Graduate Will Neutron Stars Last Forever Without Proton Decay?
- Dremmer
- · Replies 9 ·
Undergrad Why are black holes shaped like hurricanes?
- daveandjack
- · Replies 20 ·
Graduate What happens when two neutron stars collide?
- drakken1985
- · Replies 7 ·
Graduate Nature and The Universe, How can Nature being conscious, know what it is doing ?
- SBC
- · Replies 2 ·
Graduate Frustrated Over Tonight's Morgan Freeman Show
- BadBrain
- · Replies 15 ·
Graduate Relativistic Jets from Supermassive Black Holes?
- Islam Hassan
- · Replies 13 ·
Undergrad Are Black Holes Really Black and Just Holes?
- Dremmer
- · Replies 16 ·
Graduate Difference between outbursts and flares in X-ray accreting binaries
- RHK
- · Replies 1 ·
Graduate How do we know there is a timespace fabric?
- Vierstein
- · Replies 1 ·
Graduate What shape would the expanding universe have if you could hold it?
- AlbertE
- · Replies 142 ·
Graduate Why does a black hole appear black if light is also time-dilated?
- FOIWATER
- · Replies 4 ·
Graduate A could be explenation for the universe but probably not.
- AustinJones
- · Replies 15 ·
Graduate Infinite universe and big bang singularity
- kuartus4
- · Replies 26 ·
Graduate Gravitational waves and others contradictoriness
- Dinar
- · Replies 9 ·
Graduate Is the Milne model compatible with Einstein's field equation?
- andrewkirk
- · Replies 11 ·
Undergrad Why doesn't a black hole's infinite gravity pull in all matter instantly?
- Rossi_UK
- · Replies 37 ·
Undergrad Acceleration due to gravity in a galaxy?
- Bjarne
- · Replies 5 ·
Graduate Just wondering what the latest descriptions of space were.
- bill alsept
- · Replies 8 ·
Graduate How Fast Do Stars Orbit in Different Galaxies?
- Bjarne
- · Replies 2 ·
Undergrad Are there active volcanoes on Venus?
- Mehrdad1
- · Replies 8 ·
DSI Pro II showing black or grey screen instead of live view
- Chronos
- · Replies 10 ·
High School When was Halley's Comet first recognized as periodic?
- BadBrain
- · Replies 2 ·
Graduate Do neutron stars need their proton crust to stay stable?
- iced199
- · Replies 31 ·
Undergrad With the laws of physics you can get Universes?
- jackmell
- · Replies 21 ·
What Is The Sky - Gazing Into Space?
- moatasim23
- · Replies 3 ·
Graduate How Does Dark Matter Influence Gravity in Galaxies?
- keepitmoving
- · Replies 3 ·
High School Has There Been a Recent Supernova in Andromeda?
- Thecla
- · Replies 4 ·
Undergrad Matter, energy, space, time and gravity
- Dremmer
- · Replies 4 ·
Graduate Could every possible universe exist somewhere ?
- IngemarAEH
- · Replies 16 ·
List of Astronomical Associations / Astrologist in USA
- exchanger107
- · Replies 1 ·
Who Decides Humanity's Space Destinations and Why?
- sigurdW
- · Replies 9 ·
Graduate Why is the Hubble sphere expanding?
- andrewkirk
- · Replies 16 ·
Undergrad Universe Expansion = Drop in Gravity ?
- blackskynet
- · Replies 6 ·
High School Comet near the sun whose orbit is?
- dolphinsny
- · Replies 7 ·
Undergrad What Powers a Supernova Explosion?
- Xcellerator
- · Replies 2 ·
High School What happens to an empty can in space?
- bigdog7696
- · Replies 4 ·
Undergrad How big and bright is the Sun seen from 120 AU?
- beginner49
- · Replies 5 ·
Graduate Solar sailing Mercury into Venus
- Mou_Laurin
- · Replies 7 ·
Graduate Black Hole - Dark Energy and Matter Question
- Eddyb1
- · Replies 7 ·
Graduate How much hydrogen has been consumed?
- iced199
- · Replies 15 ·
Graduate Traveling to Alfa Centauri at 1/2 the speed of light
- McCartney
- · Replies 40 ·
Graduate How do we know that 74% of the universe is dark energy?
- iced199
- · Replies 5 ·
Graduate Quantum Confusion - Does not exist until it's observed and age of universe
- sshai45
- · Replies 3 ·
Graduate Can space be inferred from the senses rather than being a priori?
- John Creighto
- · Replies 6 ·
Graduate Redshift Time and the Start of the Solar System
- John15
- · Replies 3 ·
Stargazing Viewing night sky in the middle of a major city
- BadBrain
- · Replies 4 ·
Graduate Can Time Exist Before the Big Bang?
- blackskynet
- · Replies 2 ·
Undergrad Should the Astronomical Unit be replaced by the Light Second/Light Minute Etc.?
- BadBrain
- · Replies 23 ·
High School Does Space Need to Be Filled for Distance to Exist Between Two Objects?
- nick1o2
- · Replies 3 ·
High School Does the expanding universe have an edge or boundary?
- courtney1111
- · Replies 37 ·
Undergrad Astro Physics Research for Undergrads
- kptsilva
- · Replies 15 ·
Undergrad The First Three Minutes - Steven Weinberg
- s_sayed
- · Replies 24 ·
Graduate Relationship between dark energy and the strong force
- silent bob
- · Replies 10 ·
Graduate Mirror neutrons all over the science news
- skydivephil
- · Replies 20 ·
Undergrad Can quasar gets converted into pulsar?
- Mehrdad1
- · Replies 4 ·
Graduate What value is expected for baryon to photon density?
- arroy_0205
- · Replies 1 ·
Graduate How Is Satellite Orbit Speed Calculated with Atmospheric Resistance?
- Bjarne
- · Replies 3 ·
Graduate Why do photons from distant objects reach us after billions of years?
- Frank Stepien
- · Replies 15 ·
Graduate Size of universe and quantity of mass
- kuartus4
- · Replies 1 ·
Undergrad 10^80 particles in observable v unobservable universe
- robertjford80
- · Replies 45 ·
Graduate What can we expect from dark matter detection missions?
- skydivephil
- · Replies 5 ·
Graduate Is the inverse-square law valid for all cosmological distances?
- StateOfTheEqn
- · Replies 34 ·
Stargazing James Webb Telescope capability ?
- blackskynet
- · Replies 1 ·
Graduate Why do Venus and Mercury have stable axial tilts without moons?
- iced199
- · Replies 2 ·
Graduate Collision course trajectory / velocity
- CarlosMarti12
- · Replies 1 ·
Undergrad G-Forces in Space and the Human Body
- jonc151
- · Replies 8 ·
Undergrad Relation between the sol, mass, gravity, and black holes
- Jeaaas
- · Replies 1 ·
Undergrad Heliosphere's Long-theorized Bow Shock Does Not Exist
- chemisttree
- · Replies 7 ·
Graduate Carried along by the Hubble flow.
- yuiop
- · Replies 37 ·
Graduate Need specific Hubble images. Archive does not have them.
- Peb63
- · Replies 2 ·
Undergrad Position of the Sun and Moon in ECEF coordinates
- Trolll
- · Replies 3 ·
Graduate Tugs from Beyond the Observable Universe
- blackskynet
- · Replies 2 ·
Undergrad Can gravity increase on its own?
- schiz0ai
- · Replies 7 ·