Astronomy Notes – Unit 2a – Solar System
q (1) The “old” definition
o _________ (with moons)
o asteroid belt (_________)
o Kuiper belt (__________)
o Oort cloud (hypothetical)
q (2) The “new” definitions:
o A
planet is a body that orbits the Sun, is large enough for its
own gravity to make it round, and has "cleared its neighborhood" of
smaller objects.
§
_____
planets, ________ dwarf planets
o A natural satellite is an object
that orbits a planet or other body larger than itself and which is not
man-made.
§ _____ moons orbit planets
q (3) The Sun contains ________ of the system’s mass
q (4) Inner Planets
o Mercury - Venus - Earth - Mars
o __________ (rocky) planets with canyons, craters, mountains and volcanoes
o Clearly defined difference between _____________ and ____________
q (5) Asteroid Belt
o dwarf planet Ceres (also Terrestrial)
q (6) Outer Planets
o Jupiter - Saturn - Uranus - Neptune
o Gas giants whose primary mass is ______________ and _____________
o Surface or core is unknown
q (7)
Trans-Neptunian Objects (TNOs) beyond the orbit of
o where the ___________ live
o Greater orbital inclinations to the solar ecliptic plane
o More pronounced elliptical orbits
o Kuiper belt objects (KBOs)
§ Short period comets
§ Includes dwarf planet ___________ and moons
o Scattered disc objects (SDOs)
§ Includes dwarf planet Eris
o Oort cloud objects (OCOs)
§ Long period comets
q (8) Heliopause – where does the ________ ________ end?
q (9) Extra-solar systems
o Exoplanet count = ________
o Usually fast orbit gas giants
o Creative detection methods