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 Can we rotate 3D objects in 4D space?
- ramollari
- · Replies 9 ·
Can a microscopic solar system exist?
- SpikeVoyager
- · Replies 7 ·
Undergrad Can planets exist around twin or triple-star systems?
- JV
- · Replies 7 ·
Graduate A possible view of curved space/time?
- juju
- · Replies 15 ·
High School What makes an object a planet or moon rather than an asteroid?
- JV
- · Replies 14 ·
Link to Bush v. Kerry debate on the space program
- Phobos
- · Replies 1 ·
Undergrad Why doesn't the orbit increase in radius?
- IcedB
- · Replies 4 ·
Looking for a good band name having to do with the origin of the universe
- SpikeVoyager
- · Replies 27 ·
Graduate Mutual solar-extrasolar orbital foci
- Loren Booda
- · Replies 2 ·
Graduate What are the JNow RA and Dec of L4 and L5 in the Sun/Earth system?
- Valareos
- · Replies 2 ·
High School Why is blue light scattered more than red light by dust?
- ThomasJoe40
- · Replies 11 ·
Undergrad Is the Universe Curved or Flat and How Does It Affect Energy?
- bayan
- · Replies 5 ·
Graduate Why does a spinning black hole's singularity form a ring?
- Aphex_Twin
- · Replies 2 ·
Undergrad Can a Planet Turn into a Star through Gas Accumulation?
- JV
- · Replies 1 ·
Undergrad Does space expansion affect the Earth-Sun distance and atomic scales?
- colinr
- · Replies 11 ·
Graduate Challenges in Determining the Density of the Universe
- saltrock
- · Replies 1 ·
Undergrad Conditions for 2 Elliptical Orbits w/ Same Peri/Aphelion
- goleafsgo113
- · Replies 1 ·
Graduate Expansion of Universe and fine structure.
- turbo
- · Replies 15 ·
Graduate Dear Nereid and Phobos (seat belt on) can we talk about redshifts?
- turbo
- · Replies 88 ·
Undergrad The Universe is expanding Right?
- Smurf
- · Replies 25 ·
Graduate Converting State Vectors for Solar System Bodies
- kepler
- · Replies 3 ·
Why do some stars appear green in photos with red, white and blue stars?
- mee
- · Replies 15 ·
Graduate The originator of magnetic helicity?
- Antonio Lao
- · Replies 4 ·
Surprising astronomy findings from 2004
- flashgordon
- · Replies 3 ·
Graduate Can Modifying Gravity Solve the Dark Energy Dilemma?
- marcus
- · Replies 34 ·
Graduate Living in a Closed-Loop Universe?
- Aki
- · Replies 11 ·
Graduate Could Twin Planets Be Visible to Each Other in Altered Orbits?
- lubi
- · Replies 5 ·
Graduate Is There Any Gravitational Pull Between Particles Billions of Light Years Apart?
- Zuryn
- · Replies 11 ·
Undergrad What is the value of Mu needed for orbit calculations in the Earth-moon system?
- kepler
- · Replies 1 ·
Graduate Is Time Speeding Up in the Expanding Universe?
- Zuryn
- · Replies 7 ·
Undergrad How does velocity affects the shape of orbit
- goleafsgo113
- · Replies 2 ·
Graduate Could a Hollow Supermassive Black Hole Support Life Inside?
- ObsessiveMathsFreak
- · Replies 4 ·
High School Ever seen a full moon in the daytime?
- Prosthetic Head
- · Replies 1 ·
Graduate Multiple connected topology and gravitation
- humanino
- · Replies 1 ·
Object spotted in Sinus Meridiani by Mars Global Surveyor
- nymph
- · Replies 8 ·
High School Does sky color change at different latitudes and altitudes?
- one_raven
- · Replies 4 ·
Graduate What are the top candidates for dark matter particles?
- wolram
- · Replies 49 ·
Graduate Is there a hidden layer in the universe ?
- eighth man
- · Replies 7 ·
Graduate Transforming Orbital Elements from J2000 to Ecliptic Plane
- kepler
- · Replies 4 ·
Graduate Is Landing on Jupiter's Volcanic Moon Io a Viable Possibility?
- Simfish
- · Replies 2 ·
Undergrad What Determines a Star's Life Expectancy?
- Aphex_Twin
- · Replies 9 ·
Graduate Dark matter distribution mapped by weak and strong gravitational lensing
- Nereid
- · Replies 17 ·
Undergrad History of Universe (Baez timeline)
- marcus
- · Replies 8 ·
Graduate Why singularities and not exclusion?
- Gonzolo
- · Replies 8 ·
Undergrad Why is the sun's surface so cool?
- Joop
- · Replies 11 ·
Are the objects in these pictures related?
- rajesh
- · Replies 1 ·
See the attachments
- rajesh
- · Replies 1 ·
SpaceShipOne wins X Prize suborbital spaceflight competition
- Spectre32
- · Replies 3 ·
High School Why can we see the dark side of the crescent moon at night?
- StatusX
- · Replies 2 ·
Graduate Could we see galaxies that were receding faster than the speed of light?
- Mike2
- · Replies 14 ·
Undergrad We always see the same side of the moon
- Gonzolo
- · Replies 3 ·
Graduate The Spin of Mercury: 3/2 or 1/2?
- Hossam Aboulfotouh
- · Replies 2 ·
High School Sun Transit Time: Toronto vs Boston
- Jonstar
- · Replies 4 ·
High School My first thread here, about constellation
- ThomasJoe40
- · Replies 15 ·
Graduate How to calculate the time taken for the sun to cool down?
- Baggio
- · Replies 7 ·
Graduate What are the current hot issues in the standard cosmological model?
- Chronos
- · Replies 6 ·
Graduate Why does the permeability of free space have an exact value?
- DeadWolfe
- · Replies 21 ·
Undergrad Why does Meteosat's orbital period appear different to an equatorial observer?
- Jack16
- · Replies 4 ·
High School Book recommendations for learning astrophysics rigorously
- orchidpsycho
- · Replies 4 ·
Graduate Why does light/energy propagate?
- force5
- · Replies 4 ·
Graduate What is meant by expanding space
- Gonzolo
- · Replies 3 ·
Graduate Calculate the uncertainty of the distance to the clusters?
- rikpotts
- · Replies 1 ·
Graduate Brane Worlds, the Subanthropic Principle and the Undetectability Conjecture
- Vast
- · Replies 21 ·
High School How Did 19th Century Astronomers Measure the Distance to the Sun?
- T@P
- · Replies 4 ·
Graduate Is the matter of black holes in our universe?
- Gerinski
- · Replies 4 ·
Graduate Was All Matter Created During the Inflationary Period After the Big Bang?
- Curious6
- · Replies 8 ·
Undergrad What Is the Frame of Reference for Measuring Velocity?
- DrWarezz
- · Replies 22 ·
High School Is the cosmos invisible to the unaided eye?
- ostren
- · Replies 8 ·
Graduate Origin of the intracluster medium
- hellfire
- · Replies 11 ·
Graduate What keeps an interstellar gas cloud hot when it collides with the solar system?
- mee
- · Replies 6 ·
Graduate Are we ever in the present time?
- 4newton
- · Replies 2 ·
Graduate Pioneer anomaly and quintessence
- Chronos
- · Replies 1 ·
High School What Does It Mean When We Say Our Universe Is Expanding?
- kronecker
- · Replies 8 ·
Undergrad What orbits result from powered flight between Earth and Mars?
- revenant
- · Replies 3 ·
Graduate Some results from the Hubble Ultra-deep field
- Nereid
- · Replies 6 ·
Graduate How Do Gluons Affect Neutron Star Stability?
- Orion1
- · Replies 2 ·
Undergrad Moon Moving Away: Why is it Increasing?
- JV
- · Replies 2 ·
Graduate Exploring the Angle of Resolution in the Mercury Transit and Beyond
- nightcleaner
- · Replies 2 ·
Undergrad How do you determine angular size of an asteroid?
- Gillipsee
- · Replies 2 ·
Graduate Galaxy motions -> hidden superstructure (DM)
- Nereid
- · Replies 75 ·
Stargazing Picture of Jupiter's moons without a telescope
- tony873004
- · Replies 2 ·
High School Astronaut's Experience Orbiting Earth at 11K mph
- kleinma
- · Replies 3 ·
High School Can the sun rise from the west on Earth?
- Faizan
- · Replies 33 ·
Graduate Europe's long term plans for cutting edge astronomy and cosmology research
- Nereid
- · Replies 1 ·
The Big Bang and the Creator's Soup
- timejim
- · Replies 8 ·
Undergrad Why do stars emit electromagnetic waves?
- neoweb
- · Replies 14 ·
Graduate Is Our Universe the Result of a Black Hole from a Previous Universe?
- RAD4921
- · Replies 4 ·
Undergrad What is the energy of the combined body after the collision?
- ori
- · Replies 9 ·
High School Can the Speed of Light Change or Increase?
- tumor
- · Replies 32 ·
Suggestions for a black hole book title
- SpikeVoyager
- · Replies 8 ·
Graduate What Are the Implications of H. Arp's Red Shift Quanta Theory?
- wolram
- · Replies 7 ·
Graduate Is cosmology in constant trouble?
- Chronos
- · Replies 15 ·
High School What do magnitude and latitude mean in astronomy?
- A_I_
- · Replies 6 ·
High School Skywatcher Explorer 130P for deep-sky objects under light pollution?
- neoweb
- · Replies 4 ·
Humidity and Lenses: What to Do When Too Much Dust in House
- JasonRox
- · Replies 2 ·
Graduate The temperature of empty space What now?
- Jack Martinelli
- · Replies 7 ·
Graduate Statistical superposition of universes
- Loren Booda
- · Replies 1 ·
Graduate What can the GRACE Gravity Model 01 reveal about Earth's gravity field?
- sol2
- · Replies 9 ·
Graduate Is the Kuiper Belt responsible for the subtle slowdown in Bode's law?
- Rothiemurchus
- · Replies 8 ·