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 Where did the early photons go?
- John Helly
- · Replies 34 ·
High School Can big bang be a part of a loop?
- anuureeett
- · Replies 2 ·
Undergrad How feasible is home radio astronomy?
- Vanadium 50
- · Replies 93 ·
Undergrad Are primordial fluctuations the source of all structure?
- Ahmedbadr132
- · Replies 5 ·
High School What happens to information inside a black hole?
- praneel ghate
- · Replies 4 ·
Undergrad Illuminating Black Hole Shadows with Dark Matter Annihilation
- fresh_42
- · Replies 5 ·
Stargazing Castor, Pollux, Mars and the Moon
- pbuk
- · Replies 1 ·
Stargazing Partial Solar Eclipse, From Southern New Zealand
- davenn
- · Replies 1 ·
Undergrad Are There Two Suns? Exploring the Phenomenon of Sun Dogs
- Fastmamon
- · Replies 4 ·
High School Asteroid 2024 YR4 has a 1% risk of a multi-megaton impact in 2032 (now ruled out)
- mfb
- · Replies 35 ·
High School Matter density right after the decoupling
- janeczek
- · Replies 13 ·
High School Why Does Titan Have an Atmosphere While Other Large Moons Don't?
- zuz
- · Replies 16 ·
High School Venus and Jupiter Conjunction
- Charles Link
- · Replies 4 ·
Undergrad Potential biosignature found in Mars rock
- mfb
- · Replies 13 ·
Undergrad Does it make sense to build new radio telescopes?
- Line_112
- · Replies 46 ·
High School Inflation after Atacama Cosmology Telescope Results
- windy miller
- · Replies 3 ·
Graduate Could gamma-ray bursts have an intragalactic origin?
- Line_112
- · Replies 29 ·
Stargazing Orange lines on Aladin lite
- TensorCalculus
- · Replies 3 ·
Graduate Why do both poles of a radio pulsar emit radio waves?
- Line_112
- · Replies 7 ·
Undergrad Could fast radio bursts be alien radar signals?
- Line_112
- · Replies 9 ·
High School Looking for a list of astronomy collaborations
- ohwilleke
- · Replies 2 ·
High School Does Time Pass at Different Rates on Other Planets?
- mathewmcgill
- · Replies 19 ·
Graduate Self-gravitating systems and MOND
- JCTthatsME
- · Replies 11 ·
High School Realism about singularity
- windy miller
- · Replies 38 ·
Undergrad How to explain the strange pulsar in the Crab Nebula?
- Line_112
- · Replies 4 ·
Undergrad Why are continuously emitting radio pulsars not detected?
- Line_112
- · Replies 30 ·
Undergrad Time interval terminology
- 1940LaSalle
- · Replies 6 ·
Graduate Charge to mass ratio of a photon
- Karmyogi01
- · Replies 15 ·
High School Simulating the Universe's First Stars - The Population III Stars
- jedishrfu
- · Replies 5 ·
Undergrad Cosmological perturbations and CMBR anisotropies
- Ranku
- · Replies 3 ·
High School What is conformal time?
- Dark85
- · Replies 10 ·
High School Cosmic Microwave Background Stage 4 Cancelled for now
- Astronuc
- · Replies 4 ·
High School Feasibility of Sending a Radio Signal Detectable from a Neighboring Star
- Trysse
- · Replies 5 ·
High School How Can Interstellar Asteroids Be Analyzed Using Orbital Mechanics Equations?
- OmCheeto
- · Replies 22 ·
Undergrad How Does the Balloon Analogy Explain the Expansion of the Universe?
- jv11
- · Replies 5 ·
Undergrad Is Introducing a New Cosmological Model Based on Aether Theory Permissible Here?
- Starknakdfopsy
- · Replies 1 ·
Undergrad No symmetries in the Universe at the Big Bang...?
- Suekdccia
- · Replies 12 ·
High School Flatlander analogy of spherical surface as observable universe
- Catastrophe
- · Replies 6 ·
High School Conflict between the conservation of matter and the rapid expansion of our universe
- JedediahJones
- · Replies 18 ·
Undergrad Sun gravitational lensing forces
- jv11
- · Replies 11 ·
High School Where can I find easy-to-understand GAIA exoplanet data?
- Cerenkov
- · Replies 4 ·
Undergrad The impact of early galaxy formation on the CMBR
- pinball1970
- · Replies 20 ·
High School Sun's peak wavelengths and chlorophyll's green colour
- DaveC426913
- · Replies 27 ·
Stargazing How Can You Improve Your Amateur Solar Imaging Techniques?
- davenn
- · Replies 311 ·
Graduate Understanding the Gravitational Redshift Caused by a Black Hole
- Karmyogi01
- · Replies 9 ·
High School How well do we understand the formation of population III stars?
- BWV
- · Replies 7 ·
Undergrad Questions on Expansion of the Universe and Newtonian Physics
- lee_st3
- · Replies 7 ·
High School Strange spiral structure in Oort Cloud, outer Solar System
- Astronuc
- · Replies 2 ·
Undergrad How 'Messy' are Fusion Reaction Chains in Stars?
- Drakkith
- · Replies 6 ·
High School Big Bang and Infinite Universe
- Jimmy87
- · Replies 20 ·
High School Strongest hints yet of biological activity outside the solar system
- Cerenkov
- · Replies 21 ·
Undergrad How to calculate the mass within the Hubble Sphere?
- timmdeeg
- · Replies 3 ·
Graduate Hubble tension -- any resolution?
- Mordred
- · Replies 94 ·
High School Can You Ace Harvard's Galactic Quiz?
- Hornbein
- · Replies 27 ·
Undergrad Help with my Polar Aligning Star Tracker please
- LightningInAJar
- · Replies 18 ·
Undergrad Dark Matter , Dark energy and the Dirac equation
- GaloisGroup
- · Replies 3 ·
High School What Factors Influence the Survival and Growth of Accreting Bodies in Space?
- revnice
- · Replies 10 ·
High School Trying to understand orbiting objects in space
- mgsullivan24
- · Replies 8 ·
Undergrad IRAF 2025?
- mishima
- · Replies 3 ·
Undergrad If We Crack the Neutron Star Equation of State, How Will It Change Our Daily Lives?
- Alexandra Jan
- · Replies 12 ·
High School Colliding Gas Cloud to form a Star
- Omega0
- · Replies 3 ·
High School Could Black Hole Collisions Trigger a Cyclical Big Bang and Universe Rebirth?
- dvdpitch
- · Replies 19 ·
Undergrad Gravitational wave effects on different materials
- Andy DS
- · Replies 4 ·
High School Thought experiment to compare the present with the future flow of time
- witold
- · Replies 7 ·
High School Proper time of the observer resting in CMB reference frame
- ongoer
- · Replies 70 ·
How Can I Enhance My Deep Sky Images and Identify Celestial Objects?
- mad4itpete
- · Replies 8 ·
Undergrad How do you get to the conclusion that there is accelerating expansion?
- Ben vdP
- · Replies 23 ·
Undergrad Inflation Models that don't produce Multiverse?
- cosmanino2050
- · Replies 5 ·
High School What has space exploration done for me as an individual?
- zuz
- · Replies 16 ·
High School What Would You See at the Edge of the Expanding Universe?
- desertshaman
- · Replies 17 ·
High School Does an infinite universe contradict a Big Bang origin?
- DaveC426913
- · Replies 65 ·
Stargazing Small angle lunar haloes
- Bandersnatch
- · Replies 5 ·
Graduate Did scientists just find that the Universe has finite angular momentum?
- pines-demon
- · Replies 12 ·
High School Confusion regarding black hole spin
- Dark85
- · Replies 40 ·
Undergrad Mass Loss on an HR diagram
- Lizard
- · Replies 1 ·
Undergrad Magnitude where the Pale Dot is blue?
- snorkack
- · Replies 1 ·
Undergrad Is the amount of dark matter constant in the Universe?
- Ranku
- · Replies 20 ·
Graduate Classifying Milky Way planets by what they´re bound to and originate from
- snorkack
- · Replies 3 ·
Undergrad Galaxy GNZ11 33 billion light-years away
- Andy DS
- · Replies 7 ·
High School First ever recorded planetary engulfment
- Tom.G
- · Replies 3 ·
Undergrad If white holes were to exist in our Universe
- mad mathematician
- · Replies 30 ·
High School Does Sun cross planes of all binary stars?
- snorkack
- · Replies 14 ·
Graduate Black Hole TON618 - Wavelength Spectrum
- nanjo
- · Replies 38 ·
Graduate Late time and early time approximation for EOS
- djymndl07
- · Replies 0 ·
Stargazing Q: Meridian flip
- Andy Resnick
- · Replies 6 ·
Undergrad Will DESI confirm that the Universe isn't described by the ΛCDM model?
- Suekdccia
- · Replies 18 ·
High School What is dark matter?
- oxgop
- · Replies 10 ·
High School Is the Gaia Telescope's Shutdown Impacting Our Ability to Map the Milky Way?
- Hornbein
- · Replies 5 ·
Undergrad Why Do Nebulae only have Hydrogen, Oxygen and Sulfur?
- Newtons Apple
- · Replies 4 ·
Undergrad Confused about Stonyhurst Grid and jHelioViewer
- Arbu
- · Replies 17 ·
Undergrad Questions on the consequence of an evolving dark energy parameter
- Suekdccia
- · Replies 1 ·
High School Dark Matter Theory Endorsed By NASA
- Hornbein
- · Replies 4 ·
Undergrad Resolution of Peeble's ODE equation
- redgun
- · Replies 1 ·
High School An old spin to our Universe
- .Scott
- · Replies 4 ·
Undergrad How can the Universe be infinite?
- Meow12
- · Replies 6 ·
Undergrad Speediest Exoplanet System
- Tom.G
- · Replies 11 ·
High School How Can Black Holes Vary in Size if They Are Singularities?
- kickaxe
- · Replies 20 ·
High School CNO Cycle
- KingGambit
- · Replies 3 ·
Undergrad Can Staging Rockets Achieve Faster-Than-Light Travel Despite Relativity?
- benss
- · Replies 8 ·
Measuring the Solar System and Universe
- Hornbein
- · Replies 2 ·