Universe And Solar System Flashcards
These are the hottest stars, with a surface temperature of more than 37,000°F.
Blue Stars
These are warm stars, such as the Sun. Their temperature is about 10,000°F.
Yellow Stars
The coolest stars are * . Their surface temperature is less than 5,500°F.
Red Stars
When light coming from a distant star is seen through a spectroscope (an instrument that separates light into its different colors); the light we receive continues to shift toward the red area of the spectrum, which is the least powerful. This means that, since the light is becoming weaker and weaker, the stars must be traveling away from us. This makes scientists believe that our universe is expanding.
Red Shift
A swirling cloud on the planet Jupiter is a raging storm of gases, mainly red phosphorus.
Red Spot
are immense systems containing billions of stars
have different shapes: some are spiral, others are elliptical, or oval- shaped, and some are irregular
Galaxies
spiral-shaped galaxy about 100,000 light-years in diameter and about 10,000 light-years in thickness.
Milky Way
appear as dark spots on the Sun, and are believed to be cooler than the rest of the Sun. They appear in 11-year cycles.
Sunspots
the term used for a body in orbit around the Sun. The word comes from the Greek planetes, and means “wanderers
planets
term for a body in orbit around a planet
Satellite (or moon)
But when Galileo Galilei discovered the four main moons of the planet *, Johannes Kepler wrote Galileo a letter suggesting he call them “satellites” (from the Latin satelles, which means attendant). The word means the same thing as “moon.”
Jupiter
path traveled by a body in space. It comes from the Latin orbis, which means circle. Some orbits are nearly circular, but the orbits of most planets are ellipses—shaped like ovals.
orbit
also known as the minor planets, are small bodies orbiting the Sun that resemble planets. most are found between Mars and Jupiter. Usually having an irregular shape, asteroids—at least those discovered thus far—can range in size from 580 miles (940 km) in diameter, which is the size of the asteroid Ceres, to just 33 ft. (10 m) in diameter
Asteroids
are made up of frozen dust and gases, and have been described as large, dirty snowballs with icy centers. They often travel on extremely elongated orbits around the Sun. The tail of a comet, called a *, forms when the comet comes within 100 million miles of the Sun. It is then affected by the solar wind (hydrogen and helium that travel away from the Sun at high speeds), which causes a tail of dust and gases to form behind the comet.
comet, coma
fragments of comets, planets, moons, or asteroids that have broken off. It is estimated that a billion meteors enter our atmosphere every day. Contact with our atmosphere causes most to disintegrate before reaching Earth. Those that do not disintegrate completely but fall to Earth are called * .
Meteors
meteorites
occur when a star runs out of energy and shuts down. The force of gravity at its center pulls the mass of the star in on itself, forcing it to collapse. It resembles the glowing cinders of a fire that has died down. It is called a white dwarf because it emits a white glow.
White dwarfs
are also called failed stars. They lack enough energy to be true stars but are also too massive and hot to be planets.
Brown Dwarfs
is an extremely large exploding star. Just before the star dies, it releases huge amounts of energy, briefly becoming millions of times brighter than it was. Then it immediately shrinks.
supernova
are formed after a supernova explodes and shrinks. The shrunken form of the star becomes incredibly dense and compact as gravity pulls all of its matter inward. It becomes so compressed that a million tons of its matter would hardly fill a thimble. This density crushes together the electrons and protons that make up its atoms, turning them into neutrons.
Neutron stars
are believed to be rapidly spinning neutron stars that give off bursts of radio waves at regular intervals. * is a shortened version of Puls[ating st]ar.
Pulsar
are believed to be the most remote objects in the universe. Despite their small size they produce tremendous amounts of light and microwave radiation: not much bigger than Earth’s solar system, they pour out 100 to 1,000 times as much light as an entire galaxy containing a hundred billion stars.
Quasars
is created by the total gravitational collapse of a massive star or group of stars. It is the final phase of some stars, in which gravity sucks the star in on itself—it implodes rather than explodes. This makes it so dense that not even light can escape its gravitational field.
black hole
giant glowing cloud thought to be made up of dust and gas. * were thought to have been galaxies that appeared as a blur because they were so far away, but as more powerful telescopes were created, they showed that nebulae were not clumps of stars but in fact a hazy cloud of gasses. A * is illuminated by bright stars nearby.
nebula
has almost no atmosphere, and its dusty surface of craters resembles the Moon
Mercury
