Would it be plausible for a planet that had an Earth-like atmosphere with plentiful oxygen, but no life of any kind, to exist in another solar system?
a. Plausible. Life requires far more than oxygen to exist.
b. Plausible. The oxygen may have been transported there by cometary impacts.
c. Implausible. Oxygen is highly reactive and its presence in an atmosphere suggests replenishment by a living organism of some sort.
d. Implausible. Oxygen is essential to life.
Answer : c. Implausible. Oxygen is highly reactive and its presence in an atmosphere suggests replenishment by a living organism of some sort.
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What is the Great Red Spot?
A. a region of gas on Jupiter's surface that contains a great deal of iron B. a huge spinning vortex larger than Earth in Jupiter's atmosphere C. another name for Jupiter D. a place on Jupiter's surface where comet Shoemaker-Levy landed in 1992
When we see that a spectral line of a galaxy is broadened, that is, spanning a range of wavelengths, we conclude that
A) we do not have very good resolution of a star's orbital velocity. B) there are many stars traveling at extremely high orbital velocities. C) there are different Doppler shifts among the individual stars in the galaxy. D) we are actually measuring the orbital velocity of a cloud of atomic gas. E) we are actually measuring the orbital velocity of dark matter.
The energy level diagram for hydrogen
The smallest energy of an absorbed photon that will raise a hydrogen atom from its ground state to its first excited state is 13.6 eV.
a.
True
b.
False
Why is Europa considered a good candidate for the possible existence of life?
A) Strong evidence suggests that it has a deep, subsurface ocean of liquid water. B) The Galileo spacecraft found strange seasonal changes on its surface that look like they could be due to life. C) It is located within our Sun's habitable zone. D) It has a thick atmosphere with a surface pressure greater than that on Earth.