A decade ago, many astrophysicists thought that the oldest globular clusters were 14-16 billion years old. Why did this create problems, and how did new Hubble and Hipparcos data resolve them?
What will be an ideal response?
The Hubble Time seemed to be only 10-12 billion years old, so how could these clusters be older than the universe? Hipparcos and Hubble clarified the Cepheid data, making the distances and ages of the globulars less, and the universe older, so that now we think the universe is about 13.7 billion years old, and the oldest globulars about a billion years younger.
You might also like to view...
If you went to Mars, would you have to wear a space suit? Explain why or why not
What will be an ideal response?
The Galilean satellites orbit
a. Jupiter b. Saturn c. Uranus d. Neptune e. All of the above.
The dark spots in this photo (such as the one indicated by the arrow) represent what we call
A) sunspots. B) convection zones. C) coronal holes. D) solar prominences. E) Great Dark Spots.
Why do we think that Venus has so much more atmospheric gas than Earth?
A) Venus has gained much more gas through outgassing than has Earth. B) Because of its lack of magnetic field, Venus has been able to gain gas through the impacts of solar wind particles, while Earth has not gained gas in this way. C) Earth has lost much more gas to thermal escape than has Venus. D) Most of the gases that have been released from volcanoes on Earth later returned to the surface.