What arguments are cited for the existence of the Oort Cloud of comets?
What will be an ideal response?
Long-period comets have very large orbits that carry them out tens of thousands of A.U. away from the Sun. Kepler's second law tells us that the comets spend most of their time at these great distances. Because the direction of the orbit and its inclination appear random, all this implies a vast cloud of cometary objects surrounding the solar system; i.e. the Oort Cloud. Then in 2004 came the discovery of huge Sedna, the biggest solar system body found since Pluto; its orbit lies far beyond the Kuiper Belt, so it seems to belong to the Oort Cloud as well.
You might also like to view...
Which of the following best describes why we have seasons on Earth?
A) The tilt of Earth's axis causes different portions of the Earth to receive more or less direct sunlight at different times of year. B) The varying speed of Earth in its orbit around the Sun gives us summer when we are moving fastest and winter when we are moving slowest. C) The tilt of Earth's axis causes the northern hemisphere to be closer to the Sun than the southern hemisphere in summer, and vice versa in winter. D) Earth's elliptical orbit means we are closer to the Sun and therefore receive more intense sunlight at some times of year than at others.
What is "excluded" by the Pauli exclusion principle?
a. certain values of angular momentum b. precise values of both position and momentum c. electrons in the same quantum state d. none of the above
Of the following mesons, which is its own antiparticle?
a. K– b. ? c. ?+ d. none of those given
The diagram below illustrates the radioactive decay of Potassium (40K), which has a half-life of 1.3 billion years. If a lunar rock is found that currently contains 5 grams of 40K, and it is determined that the sample contained 20 grams when it was formed, how old is the lunar rock?
a.
6.5 billion years
b.
19.5 billion years
c.
2.6 billion years
d.
3.9 billion years
e.
4.6 billion years