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 Do contracting objects show red shift?
- Yashbhatt
- · Replies 25 ·
Undergrad The Meaning of 'Proportion' in Richard Feynman's Views on the Universe
- Nugso
- · Replies 18 ·
Graduate What does the Schwarzschild radius equation mean?
- MathJakob
- · Replies 11 ·
Graduate First Hyper Velocity Star Cluster Observed
- D English
- · Replies 2 ·
Stargazing Share and discuss your astrophotography
- Phobos
- · Replies 315 ·
Stargazing What's Happening in the Night Sky? Upcoming Astronomy Events to Look Out For!
- Phobos
- · Replies 284 ·
Graduate Light-cone cosmological simulations
- sketos
- · Replies 11 ·
Graduate Travelling to the edge of the Universe, 4th Dimensional Time Travel
- GetBent
- · Replies 10 ·
Graduate MOND fitting procedure for galaxy rotation curves
- devd
- · Replies 9 ·
How Fast Does Beta Pictoris b Spin?
- CygnusX-1
- · Replies 2 ·
Graduate Can a dark energy grid reveal absolute motion?
- Ookke
- · Replies 5 ·
High School Question: Expansion of the universe
- IMLearningEng
- · Replies 3 ·
Undergrad Could a planet get heavier without needing to grow in size?
- Toldox
- · Replies 3 ·
Undergrad Why can we see the CMB in every direction we look?
- cosmictide
- · Replies 3 ·
Undergrad How Is the Angular Diameter of Jupiter Measured and What Equipment Is Used?
- aldool
- · Replies 2 ·
Graduate Cosmic inflation and singularity
- sshai45
- · Replies 3 ·
High School Radiation on Mars: Does it Lack a Magnetosphere?
- thomshere
- · Replies 3 ·
Undergrad Why does gravity increase when a star dies?
- HenryKhais
- · Replies 3 ·
Graduate Questions about the multiverse theory
- e_john96
- · Replies 4 ·
Graduate What is the universe expanding into?
- aleemudasir
- · Replies 24 ·
High School How Often Do Blue Moons Really Occur?
- caters
- · Replies 17 ·
Graduate Our attempts at certainty (measurements) actually increase uncertainty
- jgreavu
- · Replies 14 ·
Earth-sized exoplanet spotted in star’s habitable zone
- reenmachine
- · Replies 44 ·
Undergrad Collision Sparks Star Birth at Our Galaxy's Edge
- CygnusX-1
- · Replies 1 ·
Graduate Can Pulsar Timing Arrays Detect Gravitational Wave Bursts with Memory?
- wolram
- · Replies 9 ·
Undergrad Is it really possible to see down to mag 8?
- logic10
- · Replies 4 ·
Graduate Sterile Neutrino Dark Matter: Case Advanced
- Chronos
- · Replies 2 ·
Graduate Information on large scale structure?
- sketos
- · Replies 4 ·
Undergrad Calculating bearing and distance between GPS tracker and target
- camerart
- · Replies 4 ·
Are green <5mW laser pointers legal to use in New York City?
- jenny_shoars
- · Replies 7 ·
Graduate Why do we observe only microwaves in the background radiation?
- genefalk
- · Replies 5 ·
Graduate Angular momentum of galaxies in galactic clusters
- Theactualbman
- · Replies 1 ·
High School Which Variable Star Has the Longest Period?
- mishima
- · Replies 5 ·
Graduate Why do alternative gravity models reject the Bullet Cluster evidence?
- Chronos
- · Replies 3 ·
Graduate When we look at cosmic web images, what do we see?
- awcrowe
- · Replies 1 ·
High School Can I use WorldWide Telescope to observe a gas cloud, star system, and galaxy?
- leroyjenkens
- · Replies 8 ·
Undergrad Time travel into the past a possibility now?
- alteredmind
- · Replies 7 ·
M42 and the Running Man nebula with Takahashi 150mm
- Astronomus
- · Replies 3 ·
Graduate Matter production during inflation
- nomadreid
- · Replies 12 ·
Graduate 4th quantisation and multiverse interactions in the Wheeler-DeWitt equation
- Quantizer
- · Replies 3 ·
Graduate BransDicke Cosmology and Accelerated Exlansion
- Quantizer
- · Replies 3 ·
Graduate What Gets 2nd Quantised in the WDW Equation: Geometry, Matter, or Gravity?
- Quantizer
- · Replies 1 ·
Undergrad How does a black hole absorb light if light has no mass?
- harshit
- · Replies 14 ·
Graduate SVT Decomposition: Definition and Purpose
- the_pulp
- · Replies 3 ·
Graduate Formation of 1st Solar System: Timeline Since Big Bang
- jing2178
- · Replies 1 ·
Graduate Superluminal Gravitational Acceleration
- Terdbergler
- · Replies 10 ·
Undergrad Iapetus equatorial ridge fell from the skies
- PhysicoRaj
- · Replies 8 ·
High School Why does Ryan Stone stop spinning in Gravity if there's no friction in space?
- k.udhay
- · Replies 22 ·
Graduate CMB occupation number in Earth frame with Doppler shift
- WannabeNewton
- · Replies 3 ·
Undergrad Is circumnavigation possible on Phobos or Deimos?
- megamind
- · Replies 2 ·
Undergrad The Sun's Next Phase: Can We Avoid Extinction?
- megamind
- · Replies 3 ·
Graduate Eternal inflation disfavored by Planck and BICEP2?
- Chronos
- · Replies 2 ·
Undergrad Why did terrestrial planets form in the inner solar system and gas giants in the outer?
- curious_ocean
- · Replies 9 ·
Graduate Found: The First Double Star That BRIGHTENS During Eclipse
- CygnusX-1
- · Replies 2 ·
Graduate Age of the Universe: Intuitive Understanding
- Ichimaru
- · Replies 2 ·
Graduate Is the Big Bang Caused by a Four-Dimensional Explosion?
- Mar
- · Replies 4 ·
Undergrad Why is angular momentum not conserved in 2 similar mass planet system?
- td21
- · Replies 1 ·
Undergrad How accurate is our image (depiction) of the Milky Way?
- Glenstr
- · Replies 5 ·
Graduate Mass-luminosity relation in radiative stars without nuclear fusion
- Ken G
- · Replies 75 ·
Stargazing How big would a neutrino telescope have to be?
- CosmicVoyager
- · Replies 4 ·
Blood moon Total Eclipse tonight
- Evo
- · Replies 26 ·
Graduate Big Rip Cosmology and Many-Worlds Quantum Mechanics
- caspiansea3
- · Replies 3 ·
Undergrad Why did Earth lose its first atmosphere but keep its second?
- curious_ocean
- · Replies 9 ·
High School How did Copernicus get the idea of the heliocentric model?
- Yashbhatt
- · Replies 13 ·
Graduate Is the universe a causal system?
- HamzahA
- · Replies 16 ·
Graduate Reconsidering the Speed of Light: A Crazy Idea on Dark Matter and the Big Bang
- genphis
- · Replies 1 ·
Graduate What would happen if the moon's orbital radius were increased?
- diffusegrey
- · Replies 1 ·
Graduate Why is Planck time distinct from spacetime at the Big Bang?
- tlnarasimham
- · Replies 11 ·
Graduate Neil deGrasse Tyson's Observable Universe
- fishtail
- · Replies 17 ·
Graduate Ideal gas laws in cosmology usage
- Mordred
- · Replies 23 ·
I captured a celestial event, could someone explain what it is?
- yatharth
- · Replies 6 ·
Graduate Why Are Saturn's Rings and Planetary Orbits Aligned Despite Cosmic Disturbances?
- anorlunda
- · Replies 5 ·
Undergrad Could dark matter affect the redshift of distant galaxies?
- kirred
- · Replies 37 ·
Graduate What does it mean when cosmologists say the universe is flat?
- mannygonzales1
- · Replies 15 ·
High School Although the wrong theories contributed to scientific evolution
- pomo
- · Replies 3 ·
High School Gravitational Constant: Earth vs Other Planets
- Emz19
- · Replies 3 ·
Where was the universe before the Big Bang?
- thomshere
- · Replies 2 ·
Undergrad How do they calculate how fast celestial objects are moving?
- Glenstr
- · Replies 8 ·
Graduate Was matter created during the big bang?
- curious_ocean
- · Replies 13 ·
Graduate What is the problem with the Big Bang Theory and seeing the early universe?
- RyanXXVI
- · Replies 29 ·
High School Why is the universe considered as cold?
- ninja
- · Replies 6 ·
Graduate Cosmological Redshift: Electron Energy Loss in Expanding Universe?
- Matterwave
- · Replies 8 ·
High School Which Telescope Offers the Best Value for Under $150?
- DHF
- · Replies 4 ·
Undergrad Unusual light rising from Martian surface
- Dotini
- · Replies 1 ·
Graduate Could the collapse of a black hole lead to the creation of a new Big Bang?
- BenZaleschuk
- · Replies 1 ·
Graduate Does BICEP2 kill Conformal Cyclic Cosmology?
- twistor
- · Replies 2 ·
Graduate What Are the Dynamics and Time Scales of Dark Matter Halos?
- oldGhost1
- · Replies 6 ·
Graduate How can we predict a Big Crunch?
- Yashbhatt
- · Replies 13 ·
Graduate Why do stars show absorption lines?
- zincshow
- · Replies 5 ·
Undergrad Gravitational Redshift and Hubble.
- piareround
- · Replies 17 ·
Graduate Significance of the 3K cosmic microwave background radiation
- cakeislife
- · Replies 9 ·
Undergrad Is the Mass-Luminosity Relationship for Main-Sequence Stars Linear?
- Agasthiyaraj L
- · Replies 4 ·
Graduate Black Hole Formation and Iron Distribution
- nehorlavazapal
- · Replies 5 ·
Graduate What sets the fusion rate in a main-sequence star?
- Ken G
- · Replies 5 ·
Graduate Critical density from Hubble time: what units does the formula give?
- marcus
- · Replies 1 ·
Graduate Does Dark Matter Surround Us Unseen?
- Quotidian
- · Replies 20 ·
Undergrad The Sun's End: Predicting the Inevitable
- flyinhigh
- · Replies 5 ·
Graduate How many particles could be crammed into the universe?
- Atomised
- · Replies 1 ·
Graduate Quantum perspectives in basic astrophysics?
- aim1732
- · Replies 4 ·
Time magazine spreads the horse manure
- phinds
- · Replies 43 ·