astronomy chapter 9

how many tons of mass are added to the Earth from meteorites each day?

300 tons of mass

what comet fragments into many pieces?

Comet Linear

what is a meteor shower?

Earth passes through sections of its orbit containing debris from a comet

asteroids also orbit the sun at?

Lagrange points, located 60 degrees ahead and 60 degrees behind jupiter in its orbit.

spherically - shaped region outside of Pluto that contains billions of comets

Oort cloud

what is the largest known orbit in our solar system?

SEDNA

what are short- period comets?

a close encounter with a large planet can deflect the comet into a smaller orbit around the sun.

what are the names of the two tails that comets produce?

a gas tail (ion tail), which points directly away from the sun and a dust tail which curves.

what is amino acid

a simple organic compound containing both a carboxyl (—COOH) and an amino (—NH2) group

what do comets produce when streaming from the nucleus?

a tail

comet Ikeya-seki has?

a very small coma, its tail stretched to a length of more than 1 AU

comet brooks has?

an exceptionally large head

because of pluto's size, many scientists think that pluto is?

an object in the kuiper belt

belt asteroids orbit in the?

asteroid belt

most asteroids orbit the sun in the ?

asteroid belt between mars and jupiter

what is the dark blue color in meteorites from?

carbon

when a comet approaches the sun, liberated gasses from the surface create a tiny atmosphere called? as well as a hydrogen envelope that cannot be seen in visible light

coma

apollo asteroids have?

highly elliptical orbits in their inner solar system.

what crosses earth's path?

highly elliptical orbits of the apollo asteroids

asteroids also have?

impact craters

jupiter's gravitational attraction produces?

kirkwood graphs in the asteroid belt where the orbital period of the asteroid is a simple fraction of jupiter's.

what are meteorites?

meteoroids pulled into our atmosphere by Earth's gravity heat the surrounding gases, causing them to grow

comet hale-bopp?

observed to eject 7 to 10 times more mass than usual during its approach of the sun in 1997

carbonaceous chondrite

or C chondrites are a class of chondritic meteorites comprising at least 8 known groups and many ungrouped meteorites. They include some of the most primitive known meteorites.

asteroids are classified by their?

orbits

these tails?

point away from the sun regardless of the direction the comet is moving.

trojan asteroids orbit the sun at?

special points in jupiter's orbit

just outside of pluto's orbit is a doughnut - shaped region of the solar system called?

the Kuiper belt

if comets that are on highly elliptical orbits are not disturbed ?--

they will have orbital periods of hundreds of millions of years called - long-period comets

tunguska impact 1908

trees flattened over an area 30 km in diameter