Reputation
971
Top tag
Next privilege 1,000 Rep.
Edit questions and answers
Badges
4 14
Newest
 Enlightened
Impact
~3k people reached

Apr
21
revised Circular formation around the moon
added 116 characters in body
Apr
21
awarded  Enlightened
Apr
21
awarded  Explainer
Apr
21
awarded  Nice Answer
Apr
20
revised Circular formation around the moon
Replace image with a cropped version
Apr
20
suggested approved edit on Circular formation around the moon
Apr
20
comment Could there be a closer star to Earth than the Alpha Centauri triple star system, excluding the Sun?
Sorry, I was assuming that a "brown dwarf" is a kind of star. I just checked Wikipedia, and it says that brown dwarfs are "substellar objects". Still, finding a brown dwarf closer than Alpha Centauri would be quite interesting.
Apr
20
answered Circular formation around the moon
Apr
20
comment Could there be a closer star to Earth than the Alpha Centauri triple star system, excluding the Sun?
The hypothetical Nemesis would be a brown dwarf in orbit around the Sun. A nearby brown dwarf that's not in orbit around the Sun would meet the question's criteria, and would not necessarily be "many magnitudes brighter" than Nemesis.
Apr
6
comment Collision of asteroid and gaseous planet - what would happen
@LocalFluff: Which is why I referred specifically to rocky or iron asteroids. SL9 was obviously less strongly held together by its own internal structure. And the question mentioned asteroids, not comets.
Apr
6
comment Collision of asteroid and gaseous planet - what would happen
@LocalFluff: I think a reasonably dense object like a rocky or iron asteroid would have more than enough internal strength to hold itself together for a while even inside the Roche limit. Very large objects like planets behave like fluids (for example, Earth is round because it's close to hydrostatic equilibrium), but smaller objects behave like solids. A body small enough to be non-spherical isn't big enough for tides to be a huge influence.
Apr
4
comment Can we observe what objects exist at the L3 positiion of planets of our solar system?
L3, unlike L4 and L5, is not particularly stable; I wouldn't expect to find much there.
Apr
1
answered Leaving the Milky Way
Apr
1
comment Leaving the Milky Way
@barrycarter: That's 28 years ship time; it's still about 2.5 million years for the folks back home.
Apr
1
comment Is the Oort Cloud actually opaque, or is the “cloud” used euphemistically because minor planets inside of it are too dim to be seen?
@WayfaringStranger: Except that it doesn't move "through the air". (Not all dictionary definitions are perfect.)
Mar
24
comment Why there is no smoke around the Sun?
Related: physics.stackexchange.com/q/26628/5646
Mar
20
revised How rare are earth-like solar eclipses?
added 145 characters in body
Mar
20
answered How rare are earth-like solar eclipses?
Mar
19
comment Shadows of Light = Space or Dark Matter?
Shadows (since they're not material objects) certainly can travel faster than light. Consider a light source at position 0, an object 1 foot away (1 light-nanosecond) casting a shadow, and a wall 100 feet away. Move the object laterally at 0.1c. It will take 100 nanoseconds for the shadow to start moving, but it will then move at 10c. Set up the angles right, and it can move infinitely fast. A shadow is not a rod or a pair of scissors.
Mar
9
comment What is the term for astronomical objects outside the solar system that are smaller than dwarf planets?
@Kyth'Py1k: Perhaps that's just because all known asteroids are within the Solar System (unless I've missed some recent discovery). I have little doubt that if we discovered an asteroid-like (or planet-like) object orbiting, say, Alpha Centauri A, we'd call it an asteroid (or planet), Wikipedia notwithstanding.