List of Figures and Illustrations: Systema Saturnium by Christiaan Huygens Start
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6 Huygens's 1656 observations of bands on Jupiter (top two) and Mars (bottom).
8 Huygens's 1656 observation of the nebulosity in the sword of Orion (now called the Great Nebula in Orion or M42).
9, 11-17, 19-25 Huygens's series of observations of Saturn and its satellite [Titan] from 1655 to 1659.
10 Huygens's March 1655 observation of Saturn showing how he saw Saturn's "arms" (as he called the extensions) to be a little thicker at their ends than where they were "attached" to the planet.
11 Huygens's 1656 observation of Saturn with a larger telescope (23 feet focal length) than before showing the "arms" and a shadow across the planet that joins the two arms.
16 Huygens's observation of Saturn in early 1656 when the planet's "arms" were not visible.
18 Huygens's observation of Saturn on October 13, 1656, showing the form he predicted it would have.
21 Huygens's observation of Saturn on December 17, 1657, showing the "arms" open as if they were handles, the first time he had seen them that way.
24 Huygens's observation of Saturn on February 12, 1659, showing the "handles" (his new term for the appendages) more open than before.
27 Diagram of a representation of the orbit of the satellite [Titan] with Saturn at the center.
28 Diagram of the orbits of the Earth (GF), Saturn (ABC), and the satellite [Titan] around Saturn (NHK and DEL). The Sun is at the center (S).
Plate between pages 32-33 Observations of Saturn by others prior to Huygens. I is an observation by Galileo in 1610. II is one by Scheiner in 1614. III is one by Riccioli from 1641-1643. IV-VII represent suggestions by Hevelius based on his theories. VIII and IX are observations by Riccioli from 1648-1650. X is an observation by Divini from 1646-1648. XI is one by Fontana in 1636. XII is one by Gassendi in 1646. XIII is from observations by Fontana and others from 1644-1645.
47 Huygens's concept of the actual form of Saturn and its ring.
49 Diagram of the relation of the path of Saturn (ADC) to that of the ecliptic and the ring plane (EC) on March 25-27, 1655.
50 [42] Top: Diagram of the relation of the path of Saturn (LMNO) to that of the ecliptic (RQ) and the ring plane (POQ) on April 9-12, 1655.

Bottom: Diagram of the relation of the path of Saturn (ST) to that of the ecliptic (XY) and the ring plane (VSX) on May 27 and 31, 1655.

51 Diagram of Saturn as seen in the telescope's field of view on October 13, 1656, indicating how the planet travels in the same direction as the rings.
55 Top: Diagram showing how Saturn's appearance to us changes due the changing positions of the Earth (E) and Saturn as they orbit the Sun (G).

Bottom: Huygens's observation of Saturn presenting its rings to us at their greatest inclination.

60 Repeat of figure at top of page 55.
63 Diagram of the orbit of Saturn (ANC) and the Earth (DEF) around the Sun (L) for the purposes of describing how Saturn's rings will vanish and produce Saturn's "round phase."