Cold and Hot Populations: Physical Characteristics
In addition to the distinct orbital characteristics the two populations display different physical characteristics.
The difference in colour between the red cold population and more heterogeneous hot population was observed as early as in 2002. Recent studies, based on a larger data set, indicate the cut-off inclination of 12° (instead of 5°) between the cold and hot populations while confirming the distinction between the homogenous red cold population and the bluish hot population.
Another difference between the low-inclination (cold) and high-inclination (hot) classical objects is the observed number of binary objects. Binaries are quite common on low-inclination orbits and are typically similar-brightness systems. Binaries are less common on high-inclination orbits and their components typically differ in brightness. This correlation, together with the differences in colour, support further the suggestion that the currently observed classical objects belong to at least two different overlapping populations, with different physical properties and orbital history.
Read more about this topic: Classical Kuiper Belt Object
Famous quotes containing the words cold and, cold, hot and/or physical:
“I am speaking now of the highest duty we owe our friends, the noblest, the most sacred—that of keeping their own nobleness, goodness, pure and incorrupt.... If we let our friend become cold and selfish and exacting without a remonstrance, we are no true lover, no true friend.”
—Harriet Beecher Stowe (1811–1896)
““Peter is poor,” said noble Paul,
“And I have always been his friend:
And, though my means to give are small,
At least I can afford to lend.
How few, in this cold age of greed,
Do good, except on selfish grounds!
But I can feel for Peter’s need,
And I WILL LEND HIM FIFTY POUNDS!””
—Lewis Carroll [Charles Lutwidge Dodgson] (1832–1898)
“We should be careful to get out of an experience only the wisdom that is in it—and stop there; lest we be like the cat that sits down on a hot stove-lid. She will never sit down on a hot stove-lid again—and that is well; but also she will never sit down on a cold one anymore.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“We best avoid wars by taking even physical action to stop small ones.”
—Anthony, Sir Eden (1897–1977)