Module 8 part 2

Why did Einstein introduce the cosmological constant into the equations of his General Theory of Relativity when describing the universe?

Einstein's equations required the universe to expand or contract; he could not imagine or accept it doing either one, so he put a factor in to stop it from moving

Which of the following spacecraft is NOT leaving the solar system?

Galileo

Which of the following is pretty good evidence that the universe began with a Big Bang?

NOT: the 3-degree cosmic microwave background radiation the fact that all the galaxies are moving toward us???

The two scientists who first discovered the cosmic microwave background radiation were:

Penzias and Wilson

The satellite that has given us the most precise measurements of the characteristics of the cosmic background radiation is:

Plank

The first search for radio messages from extra-terrestrial civilizations was called

Project Ozma

Which of the following is, to the best of our knowledge, in the habitable zone of its star:

a planet about 1.05 AU from a G-type main sequence star

Factoring in everything we currently know about the history of the universe, our best estimate for the age of the universe is

about 13.8 billion years

According to the models of the universe we discussed in this course, why do the galaxies move apart (why do we have Hubble's law)?

as a result of the Big Bang, space itself is stretching, and this stretching carries the galaxies away from each other

Where in space did the expansion of the universe begin?

everywhere at once

Which of the following is a biomarker that could be used from an observatory around a nearby star, with the right equipment, to identify the Earth as a planet with life:

free oxygen in the Earth's atmosphere

How does a period of extremely fast inflation very early in the history of the universe explain the observation that the geometry of the universe looks flat (not curved) to us?

inflation increased the size of the universe so much that the resulting universe looks flat from any point of view

In describing the universe using his equations of general relativity, Einstein assumed that it was isotropic (the same in all directions.) What recent observations have confirmed that the universe is isotropic on the large scale?

measurements of the 3-degree cosmic background radiation

Photosynthesis, once it was planet-wide, changed the atmosphere of the Earth by introducing a significant amount of

oxygen

Which of the following is a good summary of what most astronomers think about UFO reports in the popular media?

so far there is no scientific evidence that UFO's have anything to do with life outside the Earth

Which of the following did NOT happen during the first few minutes after the Big Bang?

some very massive early stars formed

When we determine the age of the universe using the Hubble Time, what important simplifying assumption goes into our calculations?

that the expansion of the universe has been happening at the same rate - neither speeding up or slowing down

The reciprocal of the Hubble constant (1/H) is a rough measure of the:

the age of the universe

Astronomers have measured that there is more helium in the universe than can be explained by the fusion in stars over the last 13 billion years. How do they think the extra helium got into the universe?

the extra helium was made during the first few minutes of the Big Bang, when the entire universe was hot enough for fusion to occur briefly

Which of the following events in cosmic history is the most recent?

the formation of life on Earth

Recent observations indicate that the universe is expanding faster today than it was a few billion years ago (that, in other words, the expansion of the universe is accelerating.) What kind of observations have led astronomers to this surprising conclusion?

the measurement of galaxy distances using Type Ia supernovae

According to our modern theories, the geometry of the entire universe (all of space-time) may be curved or warped. This is a pretty bizarre notion; what other discovery in astronomy has helped us believe that space may be able to curve or warp?

the properties of black holes

The fastest speed at which we might communicate with another technological civilization among the stars (according to our present understanding of science) is

the speed of light

One of the things that our current "standard model" of the Big Bang Theory doesn't explain is

why the temperature of the cosmic microwave background is so uniform throughout all of space