Deuterium–protium ratios in water found on these objects, especially 103P/Hartley, are notably similar to that of the Earth’s oceans. For 10 points each:
[10m] Name these astronomical objects studied by the Deep Impact probe.
ANSWER: comets
[10e] While long-period comets originate from the Oort Cloud, short-period comets originate from this region. The dwarf planet Orcus is in this region, which extends from 30 to 50 AU from the Sun.
ANSWER: Kuiper belt (“KYE-per belt”)
[10h] The comet 67P/Churyumov–Gerasimenko, which originates from the Kuiper belt, emits water vapor with a zero-point-five percent concentration of this compound. This compound was the first polyatomic organic molecule to be detected in the interstellar medium.
ANSWER: interstellar formaldehyde [or H2CO]
<Michael Bentley, Science - Astronomy> ~18597~ <Editor: David Bass>