Asteroid
* Find out where asteroids are found, how big they are, and why they are studied.
* Many asteroids are keystone species
  - like a mixture of a planetary metal core plus a crust plus the mantle in between
  - rich in frozen water, and oxygen-hydrogen rocket fuel is readily producible
  - lie outside the main belt
  - remain undiscovered
* Most asteroids are contained within a main belt that exists between the orbits of Mars and Jupiter
  - in relatively stable orbits between Mars and Jupiter
* Most asteroids are in the asteroid belt between Mars and Jupiter
  - region between the orbit of Mars and the orbit of Jupiter
  - just a jumble of minerals and rocks
  - made from the raw ingredients of the solar system , researchers believe
* Most asteroids are made of rock , but some are made of carbon or metal
  - rock, but some are composed of metal, mostly nickel and iron
  - of the small irregular variety
  - only half the size of Earth's moon
  - small and far away therefore, they are dim and hard to see
  - spheres
  - circle the Sun in a 'main belt' that lies between the orbits of Mars and Jupiter
  - have orbits between Mars and Jupiter
  - lie between Mars and Jupiter, in a vast ring called the Asteroid Belt
* Most asteroids lie in a belt between Mars and Jupiter
  - vast ring between the orbits of Mars and Jupiter
  - occur in the region between Mars and Jupiter
  - orbit in the main belt between the orbits of Mars and Jupiter
* Most asteroids orbit the sun between Mars and Jupiter in an area called the asteroid belt
* Most asteroids orbit the sun in a region between Mars and Jupiter called the Asteroid Belt
  - the asteroid belt, which is located between Mars and Jupiter
  - remain in the main belt between Mars and Jupiter
  - travel in elliptical orbits
* Some asteroids are actually nuclei of comets that are no longer active
  - also suspension feeders
  - as small as boulders
  - double bodies - an asteroid and a satellite
  - even binary pairs, orbiting around each other
  - known to have their own tiny moons
  - reddish while others are dark
  - cross the earth's orbit leaving debris which become meteors
  - even have orbiting moons
  - follow an elliptical orbit, occasionally passing dangerously close to Earth
* Some asteroids have orbits that come close to or actually cross Earth's orbit
  - unusual horseshoe orbits that are co-orbital with Earth or some other planet
  - lie beyond Jupiter's orbit, and some lie inside Mars's orbit
  - pass very close to Earth's orbit around the Sun
  - travel in eccentric, elliptical orbits which cross the orbit of the Earth
* also have very chaotic orbits because of their proximity to Jupiter
  - interfere with detection equipment so they're a useful place to hide
* are also rich in carbon, too, which can be used in rocket fuels, e.g., hydrocarbon fuels
  - among the most active echinoderms
  - assigned a type based on spectral shape , color , and sometimes albedo
  - asterozoans whose internal body parts extend into the arms
  - astronomical objects
  - at least as old as the moon
* are bigger than meteoroids and are found in sizes up to several hundred kilometers
  - meteors and are like small planets
  - bodies large enough to be detectable by telescope
  - celestial bodies
* are chunks of rock and metal left over from the formation of the solar system
  - differentiated from comets and meteoroids
  - either proto-planets that never made it or planets that blew apart in collision
  - eligible for naming when they have been numbered
  - from a solar system belt, meteors are other rocky bodies, and comets are part ice
  - generally rocky in composition ranging from carbonaceous to silicate to metallic
  - given a number indicating their order of discov- ery
  - inherently unwieldy
  - large hunks of space debris orbiting the sun
  - larger chunks of rock and are less common
  - likely to be crumbly material due to all the shock waves of impacts
* are located in outer space
  - universes
  - lumps of rock that orbit our sun
  - made of rock, metals and other elements
  - material left over from the formation of the solar system
  - miniature planets
  - minor planets
  - more like a mixture of a planetary metal core plus a mantle and a crust
  - most likely the leftovers from the creation of the universe
  - mountains of rock and metal that are found between Mars and Jupiter
* are much denser and more solidly constructed objects than comets
  - larger than comets
  - more metal-rich, like the core of the Earth, Moon, Mars and any other planet
* are much smaller than most moons and planets
  - the Earth or the Moon
  - piles of rubble held together by their own gravity
  - planets whose growth was stunted when the solar system formed
  - relatively unknown objects in our solar system
  - remnants of planets that have broken up
  - rockier than comets
* are rocky bodies found mostly in the asteroid belt, between Mars and Jupiter
* are small rocky bodies tumbling through space
  - worlds
  - small, irregularly shaped objects, that have inert and airless surfaces
* are smaller than any of the nine major planets of the solar system
  - planets, and are sometimes called planetoids
  - space rocks
  - the loose cannon of the cosmos
* are the rocky left-overs
  - leftover debris from the formation of our solar system
  - source of most meteors that have hit the Earth
  - starfish
  - video games
* become darker and redder with age due to space weathering.
* can be a few feet to several hundred miles wide.
* can cause craters to accrue
  - meteors to accrue
  - only stay in certain orbits
* can vary greatly in size and shape
* come in a variety of shapes and sizes.
* coming strainght on to earth are more dangerous than grazing the Earth's surface.
* exist between the orbits of Mars and Jupiter.
* follow nearly circular paths as do planets.
* have an airless rocky surface
  - arms that are connected to each other
  - known atmosphere
  - practically no gravity
  - seasons, too
  - smaller semimajor axes than comets
* heavenly body
* hold clues to the origin and evolution of our solar system and Earth.
* hurl through the solar system.
* includes sections.
* keep bumping in to each other, and when they do, pieces of rock break off.
* make up the asteroid belt.
* move and their apparent emission levels can vary by large amounts
  - in orbits around the Earth and many other planets, and the Sun
* orbit the sun like little planets while meteoroids usually have no specific orbit.
* provide ore to harvest.
* range from a few miles to hundreds of miles wide
  - many kilometers to a few meters or less in diameter
  - in size from a few miles in diameter to mere pebbles
* talks about asteroids in general.
* travel at different rates, depending on where they are in the solar system
  - through space trailing iridescent spider webs and making whooshing noises
* vary from different shades of brown and grey, and that's about it.
+ Asteroid spectral types
  * Asteroids are assigned a type based on spectral shape, color, and sometimes albedo. These types are thought to correspond to an asteroid's surface composition. For small bodies which are not internally differentiated, the surface and internal compositions are presumably similar, while large bodies such as 1 Ceres and 4 Vesta are known to have internal structure.
  * Asteroids are the leftover rock and other material from the formation of the Solar System. These rocks were too small to make a planet, and could not collide to form one. Most asteroids are made of rock, but some are made of carbon or metal.