Exam 1: A Modern View of the Universe

From the fact that virtually every galaxy is moving away from us and more distant galaxies are moving away from us at a faster rate than closer ones,we conclude that

The age of the universe is

On the 1-to-10-billion scale,about how far is it to the nearest stars besides the Sun?

A television advertisement claiming that a product is light-years ahead of its time does not make sense because

On the scale of the cosmic calendar,in which the history of the universe is compressed to 1 year,how long has human civilization (i.e. ,since ancient Egypt)existed?

Why do the patterns of the stars in our sky look the same from year to year?

The solar system contains about 100 billion stars.

Explain why it is so difficult to see planets around other stars.

The number of stars in the Milky Way Galaxy is approximately

The observable universe is the same size today as it was a few billion years ago.

Process of Science: Think of some ways in which you can demonstrate the following by simply looking at the sky: a)the Sun and stars lie beyond the Earth's atmosphere b)the stars are further away than the Moon

Imagine that you could drive your car in space.Assume that you can drive at a constant speed of 100 kilometers per hour.Suppose you started driving from the Sun.How long would it take,in years,to reach Earth?

Suppose we imagine the Sun to be about the size of a grapefruit.Which of the following describes the size and distance of Earth on the same scale?

What is the Sun mainly made of?

Is the actual size of the universe larger than 14 billion light years?

How many galaxies are there in the observable universe?

What do we mean by the observable universe?

How big is Earth on the 1-to-10 billion scale described in Section 1.2?

Briefly explain what we mean by the statement "The farther away we look in distance,the further back we look in time."

Consider the following statement,and explain whether or not it is sensible: It will take me light-years to complete this homework assignment.