Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
37 Cards in this Set
- Front
- Back
|
meteor
|
A bright trail or streak that appears in the sky when a meteoroid is heated to incandescence by friction with the earth's atmosphere. Also called falling star, meteor burst, shooting star.
|
|
|
meteoroid
|
A solid body, moving in space, that is smaller than an asteroid and at least as large as a speck of dust.
|
|
|
meteorite
|
A stony or metallic mass of matter that has fallen to the earth's surface from outer space.
|
|
|
rotation vs. revolution
|
rotation-The act or process of turning around a center or an axis: the axial rotation of the earth.
revolution- Orbital motion about a point, especially as distinguished from axial rotation: the planetary revolution about the sun. |
|
|
What asteroid did we land on?
|
On Valentine's Day, 2001, the NEAR-Shoemaker spacecraft successfully landed on the asteroid, Eros.
|
|
|
What are NEOs?
|
Near-Earth Objects (NEOs) are comets and asteroids that have been nudged by the gravitational attraction of nearby planets into orbits that allow them to enter the Earth's neighborhood. Composed mostly of water ice with embedded dust particles, comets originally formed in the cold outer planetary system while most of the rocky asteroids formed in the warmer inner solar system between the orbits of Mars and Jupiter.
|
|
|
Why do comets have long tails?
|
A comet's tail always points away from the sun. When a comet orbits close to the sun, it gets warm and begins to evaporate, leaving behind a tail of rock, dust and gas.
|
|
|
Where are comets located?
|
Today, most comets are located outside our solar system in part of the original cloud of dust and gas that has remained virtually untouched for billions of years. These regions are referred to as the Oort Cloud and the Kuiper Belt.
|
|
|
Where is Pluto located?
|
Pluto is located in the Kuiper Belt, a ring made of millions of icy bodies orbiting the Sun beyond Neptune.
|
|
|
What are the parts of a comet?
|
nucleus
coma hydrogen cloud dust tail ion tail |
|
|
comet: nucleus
|
relatively solid and stable, mostly ice and gas with a small amount of dust and other solids
|
|
|
comet: coma
|
dense cloud of water, carbon dioxide and other neutral gases sublimed from the nucleus
|
|
|
comet: hydrogen cloud
|
huge (millions of km in diameter) but very sparse envelope of neutral hydrogen
|
|
|
comet: dust tail
|
up to 10 million km long composed of smoke-sized dust particles driven off the nucleus by escaping gases; this is the most prominent part of a comet to the unaided eye
|
|
|
comet: ion tail
|
as much as several hundred million km long composed of plasma and laced with rays and streamers caused by interactions with the solar wind.
|
|
|
What was the spacecraft that took pictures of the sun?
|
SOHO- Solar and Heliospheric Observatory
|
|
|
convection
|
Convection is the transfer of heat by the actual movement of the warmed matter. Heat leaves the coffee cup as the currents of steam and air rise. Convection is the transfer of heat energy in a gas or liquid by movement of currents.
|
|
|
conduction
|
Conduction is the transfer of energy through matter from particle to particle. It is the transfer and distribution of heat energy from atom to atom within a substance. For example, a spoon in a cup of hot soup becomes warmer because the heat from the soup is conducted along the spoon. Conduction is most effective in solids-but it can happen in fluids.
|
|
|
radiation
|
The act or process of radiating: the radiation of heat and light from a fire.
|
|
|
Who proposed that comets are dirty snowballs?
|
Dr. Fred Lawrence Whipple
|
|
|
radiant of meteor showers
|
auroras
|
|
|
How long does it take for the sun to rotate?
|
at equater 25 days
|
|
|
What causes the Northern Lights?
|
Our sun is continually spewing positive ions (positively charged parts of atoms) into space due to the nuclear processes that keep it burning.
The flow of ions, which occurs in all directions, is called the Solar Wind and is actually a stream of protons, or hydrogen nuclei. When the particles that make up this wind near the Earth, they tend to be funneled toward the Earth’s poles by Earth’s magnetic field. When they reach our atmosphere, they are moving fast they knock electrons out of atoms in the upper atmosphere. |
|
|
Panspermia
|
Panspermia Theory suggests that life seeds came from outer space and planets exchanged life. Panspermia literally means seeds everywhere.
|
|
|
sunspot
|
Sunspots are cool, dark patches on the Sun's surface. They are caused by disturbances in the sun's magnetic field which make the sunspot about 2700°F (1500°C) cooler than the surrounding area.
|
|
|
prominence
|
A solar prominence is an cloud-like arc of gas that erupts from the surface of the Sun. Prominences can loop hundreds of thousands of miles into space.
|
|
|
solar flare
|
A solar flare is a magnetic storm on the sun, which appears to be a very bright spot, and a gaseous surface eruption. Solar flares are classified based upon their x-ray energy output at peak burst intensity.
|
|
|
granulation
|
Granulation consists of solar granules together with intergranular lanes (dark, cool areas between granules where solar material is descending into the surface). Granulation covers the visible surface (the photosphere) of the Sun.
|
|
|
coronal holes
|
Coronal holes are areas in the coronal where the Sun's magnetic field loops out into space instead of looping back into the Sun, areas of magnetic anomalies (they often occur at the poles). In X-ray photographs of the Sun, coronal holes are black areas. Coronal holes can last for months or years. The solar wind is emitted from coronal holes.
|
|
|
6 layers of the sun
|
-
|
|
|
luminosity
|
Luminosity is the total brightness of a star (or galaxy). Luminosity is the total amount of energy that a star radiates each second (including all wavelengths of electromagnetic radiation). The Sun is a as a G2V type star.
|
|
|
magnitude
|
Magnitude is a measure of brightness of celestial objects. Lower numbers represent brighter objects than higher numbers; very bright star are 1st magnitude, less bright stars are 2nd magnitude, etc.
Apparent magnitude is the visible brightness of an object from Earth. Absolute magnitude is the brightness the object would have if seen from a distance of 10 parsecs (32.6 light-years) from Earth. Bolometric magnitude includes a star's entire spectrum of radiation, not just the visible light. |
|
|
hydrostatic equilibrium
|
Hydrostatic equilibrium is a stable condition in a star in which the fluid matter within the star is at an equilibrium with respect to all forces, including the inward-pulling force of gravity, the out-ward pulling buoyancy due to pressure differentials, and the out-ward pulling forces of radiative pressure.
|
|
|
Annie Jump Cannon
|
Annie Jump Cannon (1863-1941) was an American astronomer who cataloged 225,300 stars in the HD (Henry Draper) catalog; every star is classified by its stellar spectra. Cannon and Edward C. Pickering (director of the Harvard Observatory) published the original HD catalog (9 volumes) from 1918 to 1924. The catalog was later expanded by Cannon and Margaret W. Mayall in 1949.
|
|
|
Jocelyn Bell
|
Susan Jocelyn Bell Burnell (1943- ) is an astronomer who discovered the existence of pulsars in 1967, while she was a graduate student at Cambridge University. A pulsar is a rapidly spinning neutron star that emits energy in pulses. BEll's graduate advisor (Anthony Hewish) was given a share of the 1974 Nobel Prize, but Bell was ignored. No one had any idea what these unusual objects were at the time, so the name little green men (LGM) was used. Soon, Thomas Gold suggested that pulsars were rapidly-spinning neutron stars, the remnants of a supernova.
|
|
|
Cecila Payne
|
The first Ph.D. in astronomy from Harvard University (male or female). She wrote what many consider to be the best Ph.D. thesis ever in the field of astronomy. She was the fist person to deduce that stars were composed primarily of hydrogen. However, as this flew in the face of what was accepted at the time, she apparently felt compelled to softening her stance on the correctness of this result. Today, of course, we know her work to have been correct.
Eventually, her husband, Sergei Gaposchkin, was given a "real" position at Harvard, while Cecila was forced to restrict her research into an area which was, at that time, of "secondary" importance (novae, for which she also made important contributions). |
|
|
Know the spectral classes
|
!
|
