Exam 1: Our Place in the Universe

The cosmological principle states that there is nothing special about our local region of the universe.

The early universe was composed mainly of which two elements?

The kind of mathematics that deals with change is called:

A light-year is measured in units of:

Human beings are composed almost entirely of the same elements that were created in the Big Bang.

Describe the main steps involved in the scientific method.

The scientific method is a way of proving ideas to be true.

Describe how talking about time can give us a feeling for distance.

One of the nearest stars is Alpha Centauri,whose distance is 4.4 light-years.The time it takes light to travel from Alpha Centauri to us is:

The invention of satellites advanced astronomy because telescopes on satellites can explore wavelengths of electromagnetic radiation,such as X-rays,that cannot penetrate the Earth's atmosphere.

Once a scientific theory is declared to be "true," progress in that area stops.