Open Stax

Astronomers think that most stars are born in groups, called ___

• assemblages

• bundles

• clusters

• blobs

Tags

NGSS.HS-ESS1-3

Loosely bound collections of dozens or thousands of stars, usually in an irregular shape, are called ___

• hexadecimal star systems

• open clusters

• globular clusters

• nebulae

Tags

NGSS.HS-ESS1-3

In an open cluster, the stars all orbit the cluster's ___

• central black hole

• central star

• center of mass

• perimeter

Tags

NGSS.HS-ESS1-4

NGSS.HS-PS2-4

What is the typical diameter of an open cluster?

• a few light years

• a couple of dozen light years

• a few hundred light years

• a couple of thousand light years

Very few open clusters are older than roughly 50 million years because they ___

• contain only second generation stars

• explode

• burn out

• evaporate

Tags

NGSS.HS-ESS1-3

Approximately how many open clusters have been observed?

• a dozen

• a hundred

• a thousand

• a million

How old are most globular clusters?

• less than 200 million years old

• about a billion years old

• about 5 billion years old

• over ten billion years old

What kind of elements are found in the old stars found in globular clusters?

• mostly lighter elements

• mostly metals

• mostly carbon, nitrogen, and oxygen

• mostly heavier elements

Tags

NGSS.HS-ESS1-3

The normal stars that are left in a globular cluster are mostly ___

• low mass red stars

• high mass red stars

• low mass blue stars

• high mass blue stars

Tags

NGSS.HS-ESS1-3

What is the primary focus of OpenStax in the field of Science education?

• Providing free, peer-reviewed, openly licensed textbooks

• Conducting scientific research

• Developing laboratory equipment

• Offering online science courses