Saturn’s E ring is thought to be produced by water erupting from the moon Enceladus. How does its average orbital radius (238,000 km) compare to the Roche limit of Saturn? Enceladus has a density of 1.6 g/cm3 and Saturn has a density of 0.69 g/cm3 . Saturn has an average radius of 58,232 km.

Venus can be as bright as apparent magnitude −4.7 when at a distance of about 1 AU. How many times fainter would Venus look from a distance of 7 pc? Assume Venus has the same illumination phase from your new vantage point. (Hints: Recall the inverse square law; also, review the definition of apparent visual magnitudes. Note: 1 pc = 2.1 ✕ 105 AU).   [fill in the blank] times fainter    What would its apparent magnitude be?

A certain exoplanet has an eighth of the mass of the Earth and half its diameter. The escape velocity on the exoplanet is ________ times the escape velocity on the Earth.   A 1/4   B 1/2   C 2   D 4

A small cloud in Jupiter's equatorial region is observed to be at 120.80 ° west longitude in a coordinate system that rotates at the same rate as the deep interior of the planet. Another observation made exactly 9.50  Earth hours later finds the cloud at 119.60 ° west longitude. Jupiter's equatorial radius is 71,500 km. What is the observed equatorial wind speed in kilometers per hour?

INVEST IGATION 3 1. Fill out this data table with information you have collected (from Handout B: Pluto) about the dwarf planet Pluto. Characteristics Unit Pluto Mass 1024 g 14.6 Volume 1024 Cm3 7 Density g/cm3 2.08 5,900.4 Distance from Sun 106 km 1,185 Radius km Crust Thickness km unknown Atmosphere Height km 60 km Axial Tilt degrees 122.5 Force of Gravity on a 1 kg test mass Length of Day hours

How would the solar system be different if the solar nebula had cooled, with a temperature half its actual value? [select all that apply]    options:   There would be more comets.   Life would have been very unlikely to evolve here.   There would be no comets.   There would be fewer asteroids.   There would be more asteroids.   Jovian planets would have formed closer to Sun.   Terrestrial planets would be large

The mass of an average comet's nucleus is about 1.0 x 1014 kg. If the Oort cloud contains 2.0 x 101 comet nuclei, what is the mass of the cloud in units of Earth masses? (Note: Earth's mass is 5.97 x 1024 kg.) M. Compare that with Saturn's mass. (Note: Saturn's mass in units of Earth's mass is 95.2 M.) mass of the Oort cloud mass of Saturn

If you stood on Earth during its formation, during which it captured about 1.6 ✕ 1011 particles per second, and watched a region covering 170 m2, how many impacts would you expect to see in an hour? (Notes: The surface area of a sphere is 4?r2. Hint: Assume that Earth had its current radius of 6,378 km.)

The planet Uranus was discovered in 1781, and Neptune, the next planet outward from the Sun, was discovered in 1846. Imagine you're an astronomer in 1846, and you start wondering if there's another planet out beyond Neptune. You decide to try and discover its existence using the same method that was used for Neptune. How will you do this? Group of answer choices You'll recruit a large number of astronomers to use their telescopes to carefully scan the sky in directions that are far from the ecliptic. The regions around the north and south celestial poles will probably be the best "hunting grounds" for the new planet. You'll examine Uranus and Neptune very carefully, on every clear night, for several years, to see if you can find any evidence that sunlight has been reflected off of the `new' planet, then off of Uranus or Neptune, before arriving on Earth. On rare occasions when Neptune passes in front of the Sun, as seen from Earth, you'll look carefully at the Sun (with a safe…

Imagine a trans-Neptunian object with roughly the same mass as Earth but located 50 AU from the sun. a) based on the solar nebula theory, what do you think this object would be made of and why? b) on the basis of speculation, assume a reasonable density for this object and calculate its diameter in units of Earth radii.