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 Why can't dark matter simply be ripples in spacetime?
- DanielBolstad
- · Replies 7 ·
Graduate Can Space-Time Events Be Quantized Before the Big Bang?
- geordief
- · Replies 17 ·
Graduate How WMAP satellite surveyed all over observable universe
- hitchiker
- · Replies 5 ·
Undergrad Far away galaxies moving faster than light?
- CarlosLara
- · Replies 54 ·
Undergrad Trying to understand basic gravitation
- U.Renko
- · Replies 1 ·
Undergrad Why do people think red shift is caused by big bang?
- n_kelthuzad
- · Replies 20 ·
Graduate Viewing a far away galaxy through a wormhole
- NWH
- · Replies 2 ·
Graduate Is there any gravitationally unbound' galactic clusters in observable universe
- hitchiker
- · Replies 4 ·
High School August 9, 2011 X6.9 solar flare and CME
- Astronuc
- · Replies 26 ·
Graduate Update to the BALLOON ANALOGY web page
- phinds
- · Replies 2 ·
High School Need Big Bang Theory Evidence for a school debate.
- SchoolDebate
- · Replies 11 ·
Graduate Can we measure Earth's speed relative to the Big Bang?
- Borzol
- · Replies 11 ·
Undergrad Is a Multiverse Considered a Universe or Multiple Universes?
- Flustered
- · Replies 4 ·
High School What conditions must be met before star becomes a black hole?
- Stu21
- · Replies 6 ·
Graduate Gravity speed (I know it's been beat to death, apologies in advance)
- DNMock
- · Replies 4 ·
Graduate Dark Matter Galaxy Collision Galactic Double Slit Test
- FesterCluck
- · Replies 4 ·
Graduate Density fluctuations that result after inflation
- robertjford80
- · Replies 10 ·
Stargazing What is a good aperture for a telescope collecting ISO far-infrared radiation?
- Quagz
- · Replies 9 ·
Graduate What does redshift mean at a black hole's event horizon?
- Aurora-Sky
- · Replies 3 ·
Graduate Could Quantum Mechanics Explain a Super Heavy Universe?
- mitcho
- · Replies 1 ·
Graduate How do physicists use redshift to determine the expansion of the universe?
- hitchiker
- · Replies 33 ·
Graduate How the shape of the universe affects density
- robertjford80
- · Replies 7 ·
Graduate The phase transition of the universe during inflation
- robertjford80
- · Replies 4 ·
High School What do the stars look like from space?
- Albertgauss
- · Replies 12 ·
High School Are there other periodic phenomena's other than the comet Hally?
- Karimspencer
- · Replies 4 ·
Graduate Matter at the core of a neutron star.
- CarlosLara
- · Replies 8 ·
Graduate Is matter not expanding together with the rest of the universe?
- TVI_1405
- · Replies 8 ·
Undergrad Energy source in Type II supernovae: thermonuclear or gravitational?
- goldsax
- · Replies 2 ·
Graduate Frame dragging in the Kerr-Newman metric around black holes
- eggman100
- · Replies 4 ·
Graduate Black holes and the event horizon
- thedude36
- · Replies 3 ·
Graduate Position and velocity vector of point referred to equinox
- solarblast
- · Replies 7 ·
Graduate Why Does 'a' Being Smaller Than 'a0' Eliminate μ in MOND?
- mesa
- · Replies 31 ·
Graduate Cosmological expansion of earth orbit
- Naty1
- · Replies 14 ·
Graduate Questions about (potential) variations in the Fine Structure Constant
- Lino
- · Replies 7 ·
Graduate Practical Interstellar Mission to Alpha Centauri?
- chill_factor
- · Replies 23 ·
Graduate Is the Universe Really Expanding or Are We Just Moving Faster?
- Tyah
- · Replies 3 ·
Graduate Did the universe have a beginning?
- Mononoke
- · Replies 15 ·
Graduate All things aside, how big could a black hole actually get?
- Lunar-Scooter
- · Replies 27 ·
Graduate Looking for advice on solar system integrator
- Deadstar
- · Replies 3 ·
Graduate How all matter antimatter particles annihilated after bigbang
- hitchiker
- · Replies 28 ·
Graduate Testing scalar-tensor gravity with pulsar-white dwarf binary PSR J1738+0333
- Chronos
- · Replies 1 ·
Undergrad Universe expansion is slowing down
- Myslius
- · Replies 36 ·
Undergrad A question regarding the B-V measurements of stars
- Rumor
- · Replies 1 ·
Does Matter's Mass Determine Space's Curvature?
- quantum12345
- · Replies 11 ·
Undergrad Source of Hydrogen: Where Does Our Sun Get Its Fuel?
- Zman
- · Replies 5 ·
High School What Would Happen if Earth Had Two Moons?
- SCKnight14
- · Replies 22 ·
Undergrad What is the Event Horizon of a Black Hole?
- AbsoluteZer0
- · Replies 3 ·
Graduate Are Charged Black Holes Just a Myth?
- trini
- · Replies 7 ·
Graduate A flat-torus as the geometry of space-time
- zhermes
- · Replies 6 ·
Graduate Is Infinite Inflation Possible After the Big Bang?
- PantherModern
- · Replies 25 ·
Graduate Using the CMB to verify the universe is flat
- robertjford80
- · Replies 2 ·
Undergrad How to compare stellar lifespans given luminosity and mass ratios
- tommyboo
- · Replies 5 ·
Undergrad Againwhat is a vaccum made of?
- Desraj
- · Replies 17 ·
Graduate Why is the moon's gravity differential field pointing away from the
- vin300
- · Replies 1 ·
White Dwarf, 12 Billion Years Old, Found Only 100LY Away
- Dotini
- · Replies 18 ·
Graduate Gravitational Perturbation - How does it work?
- Bjarne
- · Replies 2 ·
Can Ordinary Telescopes Detect Moon Bases?
- WhiteHawk
- · Replies 1 ·
Graduate Accretion disk around galaxy NGC 4261
- JeffOCA
- · Replies 3 ·
Undergrad Could SF6, Photosynthetic Bacteria, Hydrogen, and Ozone Make Mars Habitable?
- Frogeyedpeas
- · Replies 15 ·
Could Life Adapt to the Solar Flares of Red Dwarf Stars?
- phyzguy
- · Replies 3 ·
Undergrad Why do distant observers see events from the past when viewing far away?
- Gaddasconi
- · Replies 4 ·
Graduate When was the Friedmann-Robertson-Walker metric derived and why?
- Acker
- · Replies 3 ·
Graduate Index of Refraction of Outer/Interplanetary Space
- Jolb
- · Replies 2 ·
Graduate What is the significance of a universe emerging from nothing?
- Chalnoth
- · Replies 24 ·
Graduate Can observers at different locations see different cosmic horizons?
- Kaldanis
- · Replies 5 ·
Graduate Re: CMB Redshift Question (Visible Wavelengths)
- JArnold
- · Replies 5 ·
High School Asteroid hits moon → moon hits Earth possible?
- Blue_Jaunte
- · Replies 68 ·
High School Asteroid, Meteorite, Meteoroid, or Meteor?
- jenny_shoars
- · Replies 11 ·
Graduate Do recent observations challenge dark matter theories?
- Mononoke
- · Replies 25 ·
Graduate Pauli Exclusion Principle in Black Holes.
- CarlosLara
- · Replies 11 ·
Graduate Proportion of energy compared to mass in universe
- auntio
- · Replies 2 ·
Graduate What does a more massive neutron star constitute?
- tomjennings
- · Replies 6 ·
Graduate How Can Space Exist Without Time?
- peacerenity
- · Replies 2 ·
Graduate Gravitational waves in elsewhere of light cone
- PhysicoRaj
- · Replies 13 ·
Undergrad Solar elements and their placement
- Riptide
- · Replies 4 ·
Stargazing How do i make a telescope computerized?
- Patridor
- · Replies 2 ·
Graduate What is Jean's Creation in Relation to Interstellar Mediums?
- Mabs
- · Replies 2 ·
Undergrad Why Isn't the Moon's Shadow Line Perpendicular to the Sun-Moon Line?
- johann1301
- · Replies 8 ·
Graduate Can Jupiter Become a Stable Star?
- Bavid
- · Replies 3 ·
High School Science Fair Project Ideas for Astronomy
- Masonn
- · Replies 3 ·
Undergrad Are there any fields of astrophysics with no general relativity?
- chill_factor
- · Replies 12 ·
Undergrad How Does Visible Light from Quasars Reach Us?
- seandarcher
- · Replies 6 ·
Is Nothing Still Considered Something?
- Lensman
- · Replies 35 ·
Graduate What Happens to Sound Waves Near Black Holes?
- freddy123
- · Replies 18 ·
Undergrad What is the photon sphere and where is the singularity in a black hole?
- AbsoluteZer0
- · Replies 2 ·
Graduate How do we infer a closed universe from FLRW metric?
- pellman
- · Replies 3 ·
Graduate Is the Dark Matter Hypothesis Dead?
- LouisB
- · Replies 7 ·
Graduate How to find scale factor at recombination?
- eherrtelle59
- · Replies 11 ·
Graduate How Long Does the Bipolar Outflow Stage Last in Proto/T Tauri Stars?
- skydivephil
- · Replies 1 ·
What makes a great astrophysicist
- cre8flow
- · Replies 9 ·
High School Could the Big Bang have been triggered by a collapsing previous universe?
- KevinT
- · Replies 10 ·
High School Effects on earth from a heavier moon
- Tomp115
- · Replies 2 ·
Undergrad Is the Universe Flat or Curved?
- kaushik_s
- · Replies 38 ·
Graduate Chromosphere population inversion?
- jabowery
- · Replies 2 ·
High School Do all stars have same revolving speed?
- Ravi Mandavi
- · Replies 8 ·
High School Do black holes absorb light, or does their gravity just attract it?
- Marshallaw4
- · Replies 6 ·
Graduate Linear model uniquely implies a boundary to our Universe?
- johne1618
- · Replies 5 ·
High School How do we move around the sun?
- spark802
- · Replies 16 ·
Graduate What will Juice tell us about Europa?
- skydivephil
- · Replies 8 ·
Undergrad Density of Venus' atmosphere - historical
- PhilDSP
- · Replies 2 ·