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 Centre of mass of the observable universe
- Richmonder
- · Replies 13 ·
Undergrad Comoving mass density leads to linear cosmology?
- jcap
- · Replies 3 ·
High School Cepheid Variable Stars and Space-Time Warping
- Uzbar Zibil Tarag
- · Replies 7 ·
Undergrad How can a gas cloud collapse into a star if pressure opposes gravity?
- Justonequestion
- · Replies 27 ·
High School How much effect does the moon's gravity/size have on Mars?
- RICKYtan
- · Replies 4 ·
Graduate Variation of Hubble constant in cosmological time
- spaghetti3451
- · Replies 9 ·
High School Definition of unshifted spectral lines?
- Pilutiful
- · Replies 2 ·
Undergrad What is the Time Ordered Data set for CMB polarization?
- Buzz Bloom
- · Replies 3 ·
Undergrad Is the Force on a Particle in a Homogeneous Static Universe Always Zero?
- Higgsono
- · Replies 22 ·
Undergrad Alexander Vilenkin spontaneous creation
- momo666
- · Replies 5 ·
Undergrad Mercury's precession due to other planets
- greypilgrim
- · Replies 1 ·
Undergrad The Sun's habitable zone and orbital resonaces/stability
- PlutoXenon
- · Replies 1 ·
High School Evidence for interacting dark energy from BOSS
- wolram
- · Replies 2 ·
Undergrad How Does the Hubble Parameter Relate to Galaxy Movement?
- Komorebi
- · Replies 2 ·
High School Earth may owe its birth to a solar eruption
- CygnusX-1
- · Replies 3 ·
Undergrad Humidity when T is not constant in space
- Bankoletti
- · Replies 3 ·
Undergrad What Causes the Ring Current in Earth's Magnetosphere?
- Kara386
- · Replies 2 ·
Graduate Hubble scale and energy density during inflation
- spaghetti3451
- · Replies 1 ·
High School Is it possible Earth is a black hole?
- DIGBY STILLS
- · Replies 5 ·
Undergrad Entropy and Expansion in a Simple Universe
- Grinkle
- · Replies 40 ·
Undergrad What is the purpose of cosmological simulations in understanding dark matter?
- Silviu
- · Replies 3 ·
Undergrad How Can Data Constrain the Number of e-Folds During Inflation?
- windy miller
- · Replies 5 ·
Undergrad Does a black hole cut the fabric of spacetime as it changes
- SD das
- · Replies 15 ·
High School Why Can't We Find the Centre of the Expanding Universe?
- SD das
- · Replies 2 ·
High School Is Dark Matter physics low or high energy physics?
- oquen
- · Replies 27 ·
Undergrad Sun's Magnetic Field, Global Warming
- Arman777
- · Replies 10 ·
Graduate Gravitational waves: effect of frequency on strain
- RyuuJin
- · Replies 4 ·
High School The Early Universe and the Laws of Physics
- Sullivan Stockwell
- · Replies 1 ·
Should we invest in Mars Exploration
- FritoTaco
- · Replies 186 ·
High School Is Space an Object Capable of Bending?
- AishaGirl
- · Replies 6 ·
High School What did the universe expand into during the Big Bang?
- Pyrus
- · Replies 6 ·
Undergrad Are quark stars a realistic solution to the black hole singularity problem?
- rootone
- · Replies 6 ·
Undergrad How will the universe empty out?
- durant35
- · Replies 10 ·
Undergrad Sun elevation for ISS visibility
- Cristiano
- · Replies 2 ·
Undergrad Testing the information loss problem
- Chronos
- · Replies 1 ·
Undergrad How far out are the probes that were sent out
- Zahid Hasan
- · Replies 29 ·
Undergrad Entropy Change in Time of Universe
- Arman777
- · Replies 2 ·
High School What is the origin of the Gibbons-Hawking temperature?
- Tim Miller
- · Replies 14 ·
High School The Earth's magnetic field and moon
- hsdrop
- · Replies 11 ·
Graduate Can N-body simulations in general relativity eliminate the need for dark energy?
- phyzguy
- · Replies 26 ·
Undergrad Does the number of causal patches increase bc of expansion
- durant35
- · Replies 4 ·
Undergrad Consequence of curvature of spacetime
- SD das
- · Replies 3 ·
Undergrad Do particles create space over time? Is that expansion?
- negativzero
- · Replies 12 ·
Stargazing Understanding Kidney Beaning in Wide Field Eyepieces
- sophiecentaur
- · Replies 7 ·
Undergrad Where to find in-depth info about each star's composition?
- Guilherme Franco
- · Replies 1 ·
Undergrad How do we know we are looking back in time in space?
- DWT
- · Replies 25 ·
Graduate What Causes a Shift in Cosmic Ray Distribution on Earth?
- RyuuJin
- · Replies 6 ·
Undergrad Argument that a maximum density Universe expands linearly
- jcap
- · Replies 9 ·
High School Super-Earth Found in Habitable Zone of Nearby Red Dwarf
- CygnusX-1
- · Replies 12 ·
Why colonize Mars and not the Moon?
- lifeonmercury
- · Replies 817 ·
Undergrad Can negative pions replace electrons in atoms?
- Ranku
- · Replies 19 ·
High School What is meant by the size of the early observable universe?
- Grinkle
- · Replies 12 ·
Undergrad Where Would Ancient Intelligent Life Have Seen Cosmic Background Radiation?
- newphy
- · Replies 2 ·
High School Lawrence Krauss and shortening the lifespan of the universe
- Trollfaz
- · Replies 13 ·
High School Could Boltzmann Brains Become a Reality in the Far Future?
- Alltimegreat1
- · Replies 26 ·
Graduate Why use Earth as a gravity assist?
- JayFlynn
- · Replies 8 ·
High School Does Negative Mass Play a Role in Hawking Radiation?
- Allen_Wolf
- · Replies 1 ·
High School How Does Space Expand? Understanding Universe Expansion
- dirty dan
- · Replies 2 ·
Undergrad Plateau models of inflation after Planck
- windy miller
- · Replies 5 ·
High School Why did Aristotle arrange the planets in this order?
- Glenn G
- · Replies 5 ·
Undergrad Would a supernova in UDFy-38135539 affect cosmic expansion?
- infinitebubble
- · Replies 23 ·
High School Will an eccentric orbit become more circular over time without impacts?
- madison bond
- · Replies 6 ·
Undergrad Will the Universe one day become smaller?
- nico nico nii
- · Replies 29 ·
Undergrad Questions about the lifecycle of stars
- JohnnyGui
- · Replies 77 ·
Graduate A cosmological expansion problem too difficult for me
- Buzz Bloom
- · Replies 7 ·
High School Is the Expansion of the Universe Uniform?
- hsdrop
- · Replies 5 ·
Undergrad Are white dwarfs classified as stars without nuclear fusion?
- Jamison Lahman
- · Replies 33 ·
Undergrad CERN n_TOF experiment: 'Age of the Universe'
- infinitebubble
- · Replies 4 ·
Undergrad Observing Naked Singularities: Implications for Quantum Gravity
- windy miller
- · Replies 1 ·
High School Do we still live in a Big Bang Singularity?
- ivant6900
- · Replies 14 ·
Undergrad Is it possible to travel between the multiverses?
- Director_Mouse
- · Replies 3 ·
Undergrad Using big data to identify astronomocal data bias
- Chronos
- · Replies 4 ·
Stargazing When and where is the best time to view the 2014jo25 asteroid?
- hsdrop
- · Replies 6 ·
High School Why doesn't dark matter reside in gas clouds?
- wolram
- · Replies 4 ·
Undergrad Why Can We Still Observe the Cosmic Microwave Background?
- JulienB
- · Replies 7 ·
Undergrad Curvature and the size of the Universe
- CassiopeiaA
- · Replies 20 ·
Undergrad Is there a relationship between dark matter and anti-matter?
- Dade Murphy
- · Replies 6 ·
Graduate Micrometeorites and Karman effect
- Arac15
- · Replies 1 ·
Undergrad Why does 10^50 × 10^24 × 10^24 give 10^98 instead of 10^80?
- Travois
- · Replies 9 ·
Graduate Understanding Expansion of Space
- Zachary Markham
- · Replies 54 ·
High School Where have we looked, or are looking, for life?
- Jarvis323
- · Replies 9 ·
Graduate Spectral Classification Syntax for Binaries
- Solkar
- · Replies 7 ·
High School Will eLISA have the potential to detect early universe GWs?
- binbagsss
- · Replies 3 ·
Undergrad What causes retrograde rotation in planets and moons?
- Avimanyu Ray
- · Replies 8 ·
Undergrad Energy-momentum tensor and Friedmann Equations
- Diferansiyel
- · Replies 8 ·
High School Naive Calculation of the Age of the Universe
- jeffbarrington
- · Replies 3 ·
Undergrad Big Bang timing: according to what frame of reference?
- Sophrosyne
- · Replies 5 ·
Undergrad Is a superflare capable of changing a planets orbit?
- Edward Barrow
- · Replies 18 ·
Undergrad Can we predict the Sun's path accurately?
- Trainee Engineering
- · Replies 10 ·
High School Orbital mass ratio in the Milky Way using escape velocity vs gravitational force
- TreeLover
- · Replies 2 ·
Stargazing Considerations for size of telescope survey
- BOAS
- · Replies 2 ·
High School How can we see Background radiation
- Addez123
- · Replies 2 ·
High School Could the universe be eternal with the Big Bang as a fluctuation?
- mcronald
- · Replies 3 ·
Undergrad Can orbital motion substitute for rotation in maintaining a magnetic dynamo?
- Althistorybuff
- · Replies 7 ·
High School Does every elementary particle eventually decay into quarks?
- zinq
- · Replies 13 ·
Undergrad Defending the Earth from meteors using lasers
- Dovla
- · Replies 44 ·
Undergrad Does bone and muscle loss in microgravity matter if you stay in space?
- John Morrell
- · Replies 1 ·
Undergrad New Wired article on "where's the antimatter"
- jnorman
- · Replies 9 ·
High School Finite Universe vs. Uncertainty Principle
- Helios
- · Replies 15 ·
Insights Q&A with Universe Today's Fraser Cain
- Greg Bernhardt
- · Replies 4 ·