Astronomy | Astrophysics Answers

1. What is the relationship between gravity and escape velocity?
2. Why is it termed as a black hole? Will the sun become a black hole?
3. What is spaghettification? Why does this phenomenon happen?
4. What are the assumptions of space-time as stated?
5. What is gravitational redshift?

Comets in the Solar System orbit the Sun in the same way the planets do but they are highly elliptical orbits.  A partial list of comets can be found here - <span style="font-size: 10.5pt; color: rgb(17, 85, 204); background-color: transparent; font-variant-numeric: normal; font-variant-east-asian: normal; text-decoration-line: underline; text-decoration-skip-ink: none; vertical-align: baseline; white-space: pre-wrap;">https://nssdc.gsfc.nasa.gov/planetary/factsheet/cometfact.html</span>.  From this list, choose two comets and calculate the Kepler ratio for each of these comets orbiting the Sun.  Compare the ratios and determine whether or not Kepler’s third law applies for comets around the Sun in a galaxy.

To date, we have discovered 4375 exoplanets (planets that are orbiting a star other than our Sun) and of these, there are 3247 different exoplanet systems.  Of these systems, there are 11 that have at least six planets. Choose one of these systems (not our solar system) and for that system, randomly select four planets.  For each of these planets, record (or calculate) the mean orbital radius and orbital period (in units of your choosing).  Then use this information to calculate the Kepler ratio for each of these planets orbiting its star.  Compare the ratios and determine whether or not Kepler’s third law applies for exoplanets around their star other than Earth.

Can binary stars produce supernova even if these binary stars are both low mass stars? 

1.     What is peroxysms? How does it affect stellar activities?

2.     What will be the effect/implications to the Earth when the Sun turns from sub-giant to giant star?

3.     Can carbon atoms/molecules be formed through stellar activities?

4.     Up to what elements do low mass and high mass stars produce due to their stellar activities?

5.     What are the two forces that experience by the stars that influence their activities? 

You find yourself on a planet (Radius = 2.33 x 10⁷m where a 2.00 kg mass has a weight of 32.0 N. What is the escape velocity from this planet ? 

Star S2 has been observed orbiting around Sgr A* at the center of the Milky Way. At closest approach it is 17 light hours from Sgr A*, with a velocity of 5000 km/s. Assuming a circular orbit for S2, calculate the mass of the black hole at the center of the Milky Way

1.1What features of the earth (our planet) enables life to exist?

The mass of the Earth of the Earth is approximately 6.0x1024kg while the mass of the Moon is 7.3x1022kg. The distance between both bodies is 3.9x108 m. What is the gravitational force between the Moon and the Earth?

There are four planets in our solar system with a large number of moons; Jupiter, Saturn, Uranus and Neptune.  Choose one of these planets and for that planet, randomly select five moons.  For each of these moons, record (or calculate) the mean orbital radius and orbital period (in units of your choosing).  Then use this information to calculate the Kepler ratio for each of these moons orbiting its planet.  Compare the ratios and determine whether or not Kepler’s third law applies for moons around a planet other than Earth.