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 Is Gravitation Responsible for the Stability of the Universe?
- Souhardya Nandi
- · Replies 9 ·
High School Distance between the Earth and The Moon
- mr1batman
- · Replies 10 ·
Insights The Friedmann equation and cosmological models
- Arman777
- · Replies 6 ·
High School Are Black Holes Actually Giant Neutron Stars Cloaked in an Event Horizon?
- Jason R Carrico
- · Replies 70 ·
Undergrad Star spectra and star color relation
- nmsurobert
- · Replies 3 ·
High School What's the deal with dark matter
- Snooch
- · Replies 45 ·
High School Can the Solar System's Chaos Lead to Earth's Sudden Demise?
- wolram
- · Replies 6 ·
Graduate Entropy and derivations - is my logic faulty?
- Nick Prince
- · Replies 34 ·
Undergrad New Kepler results (8th planet around Kepler-90)
- mfb
- · Replies 29 ·
Undergrad Low mass limit of a neutron star
- tzimie
- · Replies 26 ·
Undergrad Friedmann Equation - Positive Curvature
- Arman777
- · Replies 12 ·
Insights A poor man's CMB primer part 5: quantum seeds
- bapowell
- · Replies 10 ·
High School Why does the multiverse theory have only 4 levels?
- Suekdccia
- · Replies 2 ·
High School Does the multiverse really include ALL outcomes?
- Suekdccia
- · Replies 2 ·
Stargazing Programable telescope that will point to any spot on Earth?
- David Berger
- · Replies 11 ·
Graduate Does zero exist in the energy term?
- SeM
- · Replies 1 ·
Graduate Equation of State w=1: Why Not Considered in Cosmology?
- Demystifier
- · Replies 4 ·
Undergrad Are there galaxies with 2 cores?
- Gerinski
- · Replies 9 ·
High School Do we see things slower the further away they are?
- EmileJ
- · Replies 3 ·
Undergrad How to measure time in the early universe?
- Cosmology2015
- · Replies 18 ·
Undergrad What is the acceleration of expanding space?
- DAirey
- · Replies 43 ·
High School How does the Aguirre-Gratton model create a no-boundary universe?
- relatively-uncertain
- · Replies 5 ·
High School Is Everything in the Expanding Universe Growing Along with It?
- Gedanken
- · Replies 52 ·
Undergrad How did time move forward during the Big Bang?
- DAirey
- · Replies 13 ·
Stargazing Is it nebulosity or an artefact?
- sophiecentaur
- · Replies 28 ·
High School How do astronomers find the "parallax angle" of a star?
- Karagoz
- · Replies 25 ·
Stargazing For those aurora chasers -- a heads up
- davenn
- · Replies 52 ·
Undergrad Is the Friedmann Space-Time Observable Without Dark Energy?
- fresh_42
- · Replies 8 ·
Graduate Deriving vernal equinox reference angle from Keplerian elements
- Philosophaie
- · Replies 1 ·
Graduate New high-redshift quasar age issue
- sebastian_1
- · Replies 1 ·
Undergrad Transit Photometry: Questions about Detecting Exoplanets
- le chat
- · Replies 5 ·
High School How does spacetime curvature affect the motion of matter?
- laymanB
- · Replies 18 ·
High School Is information about infalling objects preserved in Hawking radiation?
- Will K
- · Replies 27 ·
Undergrad How long would it take for gas to leak out of a space box?
- Albertgauss
- · Replies 19 ·
Undergrad Expansion Rate of Cosmic Bubbles
- Thuring
- · Replies 24 ·
Undergrad Entropy of the last scattering surface and today's universe?
- Astrotek
- · Replies 5 ·
Graduate How to calculate ambient temperature in space or in orbit?
- SoRobby
- · Replies 18 ·
Undergrad Quasar Number Densities and Lifetimes
- aurora7790
- · Replies 1 ·
Undergrad Is high redshift data a problem for ΛCDM?
- ohwilleke
- · Replies 7 ·
High School Optical eyepieces for star observations
- bruha
- · Replies 17 ·
Undergrad Why haven't Martian ice core samples been studied?
- Rubidium_71
- · Replies 5 ·
Undergrad Why is neutron star interesting to physics ?
- Leonardo Machado
- · Replies 8 ·
Undergrad What happens if two black holes collide
- Dalton Peters
- · Replies 12 ·
High School Bouncing cosmology as an alternative to the Big Bang
- ISamson
- · Replies 10 ·
Undergrad Why is the time of formation of this Black Hole in question?
- SWB123
- · Replies 15 ·
Undergrad Fly-by anomaly is back with Juno
- mfb
- · Replies 1 ·
Undergrad What is the Cause of Space Expansion?
- KurtLudwig
- · Replies 49 ·
High School Are there any SPH planet collision simulators?
- MrQuack
- · Replies 19 ·
Undergrad Action Dynamics of the Local Supercluster
- |Glitch|
- · Replies 7 ·
Undergrad Can someone explain the Higgs Boson and its significance in particle physics?
- Souhardya Nandi
- · Replies 3 ·
High School A photon left galaxy G, 12 by ago and is reaching Earth now
- Serifos
- · Replies 13 ·
Undergrad MUST every possible thing happen in a Tegmark L1 Multiverse?
- andrewkirk
- · Replies 4 ·
High School How did this Black Hole come to exist?
- wolram
- · Replies 5 ·
Undergrad Will the acceleration of the expansion of universe ever decrease?
- Souhardya Nandi
- · Replies 11 ·
Undergrad Can Hubble Red Shifts be Gravitational Red Shifts?
- Tom Mcfarland
- · Replies 24 ·
Undergrad Holographic principle versus no-cloning
- nomadreid
- · Replies 2 ·
Undergrad GW170608: Observation of a 19-solar-mass binary black hole coalescence
- websterling
- · Replies 24 ·
Undergrad Maintaining interest in the new 'private' space race
- Posy McPostface
- · Replies 22 ·
High School Balloon Analogy - 3D universe on a 2D plane
- Souhardya Nandi
- · Replies 10 ·
High School Life is less likely on exoplanets
- wolram
- · Replies 19 ·
High School Debate about how a light year can be used
- Harshu Pande
- · Replies 10 ·
Undergrad CMB and the reference point for vacuum energy
- nomadreid
- · Replies 3 ·
Stargazing Southern sky image: Southern Cross, Coal Sack, Omega Centauri
- davenn
- · Replies 8 ·
High School Can the Sirius Star System Support Physical Life Amidst Its Unique Conditions?
- bluecap
- · Replies 3 ·
Graduate What Factors Influence the Habitability of Exoplanetary Systems?
- wolram
- · Replies 2 ·
Undergrad Tidal effects on Earth's rotation and moon's orbit
- Buzz Bloom
- · Replies 10 ·
Undergrad Do Solar Tides affect Earth's Orbit?
- Buzz Bloom
- · Replies 18 ·
Undergrad Dark Matter and Dark Energy Conundrum
- Charles Fichter
- · Replies 18 ·
High School Could de Sitter space exist in the heat death of an expanding universe?
- laymanB
- · Replies 8 ·
High School Simulation: Our Solar System's Hyperbolic Residents
- tony873004
- · Replies 2 ·
High School Jupiter's gravitational pull on the Sun and Earth
- Glenstr
- · Replies 28 ·
High School What would happen if you take a piece of a pulsar
- johnpro1
- · Replies 1 ·
High School Does the Universe have finite or infinite size?
- fxdung
- · Replies 20 ·
High School Scale Invariance and dark matter/dark energy
- aokrongly
- · Replies 6 ·
Undergrad Where in our solar system are asteroids that contain ammonia
- Tristan27
- · Replies 7 ·
Undergrad Unraveling the Mysteries of Gravity: From Light Bulbs to Spiral Galaxies
- Dan Nixon
- · Replies 7 ·
High School What if the universe's expansion is actually slowing down?
- Robert Hoffmann
- · Replies 6 ·
Undergrad Can we experimentally understand the interior of a star?
- Phys12
- · Replies 3 ·
High School Dark matter not found in globular clusters orbiting MilkyWay
- Gordon Potter IV
- · Replies 6 ·
Undergrad Cosmological constant and rate of expansion of the universe
- Ranku
- · Replies 3 ·
High School Does scale invariance explain cosmic expansion without dark matter?
- wolram
- · Replies 17 ·
High School Implications of gravitational waves from the Big Bang?
- laymanB
- · Replies 12 ·
High School Could time move inside a black hole?
- whatdoctor
- · Replies 6 ·
Undergrad Could the Big Bang's Location Be Defined by Gravitational Forces?
- Ozfer
- · Replies 21 ·
Undergrad Dark matter and energy may not exist?
- Phys12
- · Replies 1 ·
Undergrad Could vacuum decay save multiverse ideas?
- Suekdccia
- · Replies 1 ·
Undergrad Could dark matter be too reflective to detect?
- Jeth Orensin
- · Replies 5 ·
Undergrad How does the speed of light affect expansion acceleration?
- Joe Fatuch
- · Replies 15 ·
Undergrad Is There an Extra Time Dimension in Paul Steinhardt's Cyclic Model?
- lolofromfrance
- · Replies 4 ·
Undergrad What does BGC wobbling reveal about dark matter interactions?
- Arman777
- · Replies 7 ·
Stargazing How hard is it to find filtered color bands using telescope?
- spacetimedude
- · Replies 1 ·
Undergrad How Bright Would the Milky Way Look If It Had No Dust?
- CygnusX-1
- · Replies 1 ·
Undergrad What % of the heavy elements are produced by kilonovas vs. supernovas?
- bbbl67
- · Replies 38 ·
Undergrad What is the universe expanding into ? Eternal inflation
- windy miller
- · Replies 1 ·
Graduate Milancovitch cycles and how they relate to seasons
- caters
- · Replies 4 ·
High School How do scientists detect spacetime ripples if spacetime isn't real fabric?
- mr1batman
- · Replies 12 ·
High School Gravitational Wave Stretching: LIGO Arm vs Light
- Alfred Cann
- · Replies 5 ·
High School Did a Star Go Supernova Twice?
- mfb
- · Replies 16 ·
Undergrad Magnetic field of Solar System planets
- Pedro de la Torre
- · Replies 4 ·
Undergrad Does Entropy Change on Horizons?
- friend
- · Replies 12 ·