Astronomy | Astrophysics Answers

is any substance that is not a solid,not a liquid,not a gass?

where is the center of earth?

how much the mass of sun?

where is the universe situated because every thing situated in another thing?
eg=atom in matter,matter in earth,earth in universe,universe in ?

One of Saturn's moons has an orbital distance of 1.87 x 108 m. The mean orbital period of this moon is approximately 23 hours. Use this information to estimate a mass for the planet Saturn.

somebody is still, but yet moving at 106,560 km/h (approximately, the speed of earth around the sun). How can a scientist measure and be able to rate such speed?

A student sighted on a distant lamppost, and then walked a distance of 15 meters perpendicular to the line-of-sight. After setting the pin 2, the student measured the distance between the two pins and found it to be 2.8 cm. The distance from the thin nail to the pin 1 was 45.0 cm. Calculate the distance from the student's original location to the lamppost.

According to http://nedwww.ipac.caltech.edu/forms/byname.html is this star classification right, if not please correct it?

Galaxy name: NGC 628
Galaxy Type: spiral
Your Observed Color: purple, bluegreen, & red
Spectra? Yes
# of emission lines: 2
Description of spectra: 4221.0 to 5074.0 A, 2 emission lines and 3 absorption lines

Derive an Expression for the tidal force for the earth- moon system and show that its magnitude depends on the latitude. Explain tidal bulge on the basis of this expression.

Explain how we estimate the effective surface temperature of the Sun.