The proposed supercontinent that 200 million years ago began to break apart and form the present landmasses.
What is pangea?
100
The brightness of a star when viewed from Earth.
What is apparent magnitude?
100
A cloud of gas and/or dust in space.
What is a nebula?
100
A collapsing cloud of gas and dust destined to become a star; a developing star not yet hot enough to engage in nuclear fusion.
What is a protostar.
100
The ___________________ is far below the surface and the beginning of the volcano.
What is deep submarine stage?
200
The process by which plate tetonics produces new oceanic lithosphere at ocean ridges.
What is sea-floor spreading?
200
The apparent brightness of a star if it were viewed from a distance of 32.6 light-years; used to compare the true brightness of stars.
What is absolute magnitude?
200
A group of stars, dust, and gases held together by gravity.
What is a galaxy?
200
An exploding star that increases in brighness many thousands of times. During this stage, a star becomes millions of times brighter than its pre- stage.
What is a supernova?
200
There is a new eruption and an ash cloud is seen. Sometimes cinder cones are formed.
What is the secondary activity stage?
300
The process by which oceanic crust sinks beneath a trench and back into the mantle at acolliding plate boundary.
What is subduction?
300
A telescope that uses a lens to bend and concetrate the light from distant objects.
What is a refracting telescope?
300
A law that states that the galaxies are retreating from the Milky Way at a speed that is proportional to their distance.
What is Hubble's Law?
300
A massive star that has collapsed to such a volume that its gravity prevents the escape of everything. including light.
What is a black hole?
300
The Volcano is still under the water but is closer to the surface.
What is the shallow submarine stage?
400
The theory that proposes that Earth's outershell consists of individual plates that interact in various ways and thereby produce earthquakes, volcanoes, mountains, and the crust itself.
What is plate tectonics?
400
A telescope that concentrates light from distant objects by using a concave mirror.
What is a reflecting telescope?
400
One of two stars revolving around a common center of mass under their mutual gravitational attraction.
What is a binary star?
400
A star that exhausted most or all of its nuclear fuel and has collapsed to a very small size, believed to be near its final stage of evolution.
What is a white dwarf?
400
During his stage the volcano is above sea level and is in the shape of a shield.
What is the shield building stage?
500
A boundary in which two plates slide past each other without creating or destroying lithosphere.
What is transform fault boundary?
500
A concentration of gases above the solar surface that appears as a bright archlike structure.
What is prominence?
500
A star whose brightness varies periodically because it expands and contracts; a type of pulsating star.
What is cepheid variable?
500
A star is npot considered born until the process if ____ begins.
What is fusion?
500
The ________ stage is when the land was above sea level has now been eroded away.