Chapter 10 AST 1002
At certain distances from the Sun, asteroids in the main asteroid belt are in an orbital resonance with Jupiter, creating gaps in the belt called Kirkwood gaps. Jupiter orbits the Sun with a period of 11.9 years. Which of the following is not a period of an asteroid that is in an orbital resonance with Jupiter?
3.79 years
_______ are mostly rock, whereas _____ are mostly ice.
Asteroids, comets
Determine whether each item is a property of asteroids, Kuiper Belt Objects (KBOs), or both.
Asteroids: - mostly reside in a belt between Mars and Jupiter - mostly rock and metals - include Vesta Both: - majority are small bodies - have similarities to some moons KBOs - mostly reside in a belt extending 20 AU beyond the orbit of Neptune - similar in composition to comets - include Charon
Comets and meteors are objects that are sometimes seen moving through the sky. Compare and contrast the different characteristics of these two types of objects.
Comet: - dirty snowball - approximately 1 km in size - observed as it travels through the Solar System - changes position on the sky within days - same object may return to the sky in approximately 50 years Meteor: - caused by object < 10 m in size - observed as it travels through Earth's atmosphere - changes position on the sky within seconds - often burns up in Earth's atmosphere - sometimes reaches the ground
A relatively small piece of debris chipped off of a comet or asteroid approaches Earth from interplanetary space, enters Earth's atmosphere where it is heated white-hot and burns, then strikes the ground. Identify each stage of this object's path.
From left to right: meteorite meteor meteoroid
Comets that originate in the _______ tend to have orbits near the ecliptic.
Kuiper Belt
Comet Hale-Bopp has an orbital period of over 2500 years, Halley's Comet has an orbital period of 75 vears. and Comet Encke has an orbital period of 3 years. Assume they all began with the same composition. Rank these comets by the amount of ice and volatile materials they lose over 1000 years, from lowest proportion to highest proportion.
Least ice lost: Comet Hale-Bopp Halley's Comet Comet Encke Most ice lost
Comet Halley, with an estimated initial mass of 2.2 × 10^14 kg, loses about 1.1 × 10^12 kg each time it passes closest to the Sun. This comet was first discovered in 240 BC and has a period of 75 years. It was last at perihelion in 1986. How much mass has Comet Halley lost between its discovery and the last time it was at perihelion?
Mass loss total= 3.2626 x 10^13 kg Solution: orbits= year(perihelion) - year (discovery) / orbital period
Comets that originate in the _______ tend to have long periods
Oort Cloud
Classify each of the objects of the Solar System as planet, dwarf planet, or small Solar System body.
Planet: - Venus - Uranus - Mars - Neptune - Earth Dwarf planet: - Pluto - Ceres - Eris Small Solar System body: - comets - most asteroids
How do the two different comet tails behave as the comet approaches the Sun?
The lighter tail is pushed directly away from the Sun, whereas the heavier tail trails behind curved toward the path of the comet.
Choose the correct statement or statements about the asteroid belt.
The main asteroid belt is a region between the orbits of Mars and Jupiter lying between about 2.1 and 4.1 AU from the Sun.
What are Trojan asteroids?
Trojan asteroids that share the orbit of Jupiter
Pluto was discovered in 1930 and declared the ninth planet of our Solar System, but in 2006 the International Astronomical Union changed Pluto's status to dwarf planet. Which of the statements are true of Pluto and which make it a dwarf planet?
True and qualifies Pluto as a dwarf planet: - Pluto is in orbit around the Sun. - Pluto is massive enough that its own gravity has pulled it into a round shape. - Pluto has not cleared the neighborhood of its orbit. True but unrelated to dwarf planet status: - Pluto has a moon named Charon. - Pluto has moons. False: - NASA mission named Voyager visited Pluto.
Which of the statements are true of Pluto and which are false?
True: - far smaller than all classic planets - tidally locked to one of its moons - sometimes orbits closer to the Sun than Neptune False: - orbit is circular, similar to Earth's - member of the Oort cloud - composed of metallic and molecular hydrogen
A typical asteroid in the asteroid belt is closest to the size of
a house
The orbits of _____ are most likely to be found near the ecliptic plane, whereas _____ orbit in any plane.
asteroids, comets
A comet develops two tails of different composition as it approaches the Sun. What are the two tails primarily composed of?
dust and gas
The combined mass of the asteroid belt is
less than the mass of Mars
What percentage of the initial mass of the comet is the total amount of mass lost?
percentage= 14.83% Solution: percentage= (mass loss total / mass initial) x 100%
