Cometary impacts with Jupiter
A) are impossible to observe from Earth.
B) are spectacular but do not teach us much.
C) have been observed from Earth at least twice.
D) are extremely rare.
E) would not be catastrophic if they happened on Earth.
Question 2
What is the primary visible color of an emission nebula?
A) blue due to ionized helium atoms
B) red due to the H line of hydrogen
C) black, because of dust
D) blue from the scattering of light off the tiny molecules
E) red because of reddening by dust
Blue light is scattered more than other wavelengths by the gases in the atmosphere, giving the Earth
Earth as viewed from Lunar orbit during the Apollo 8 mission, Christmas Eve, 1968. Africa is at the
Earth with Rings
Current and future trends and impacts (IPCC)
Astronaut Rachel leaves Earth in a spaceship at a speed of 0.960c relative to an observer on ...
Earth’s Early Atmosphere