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Space Topics: Voyager
Raw Image Data from the Voyager Mission to Saturn
Credit for these images belongs to NASA, the Jet Propulsion
Laboratory, the Rings Node of the Planetary Data System, and the SETI Institute.
The images on these pages come from the Imaging Science Subsystem (ISS) on
the Voyager spacecraft. Voyager ISS consisted of two vidicon cameras on
each spacecraft. The design was based upon those of Mariner 10. The cameras
both produced square images 800 pixels on a side. The wide-angle
camera had a field of view of 3.169 degrees (giving pixels 0.00396 degrees
or 0.06912 milliradians across) and the narrow-angle
camera had a field
of view of 0.424 degrees (giving pixels 0.000530 degrees or 0.00925 milliradians
across). Each camera was fitted with an eight-position filter wheel:
| Wide-angle camera |
Narrow-angle camera |
| Filter |
Center
Wavelength (nm) |
Filter |
Center
Wavelength (nm) |
| 0 |
Methane-JST |
619, narrowband |
0 |
Clear |
460, wide open |
| 1 |
Blue |
480, broadband |
1 |
Violet |
400, broadband |
| 2 |
Clear |
460, wide open |
2 |
Blue |
480, broadband |
| 3 |
Violet |
400, broadband |
3 |
Orange |
615, broadband |
| 4 |
Sodium-D |
589, narrowband |
4 |
Clear |
460, wide open |
| 5 |
Green |
585, broadband |
5 |
Green |
585, broadband |
| 6 |
Methane-U |
540, narrowband |
6 |
Green |
585, broadband |
| 7 |
Orange |
615, broadband |
7 |
Ultraviolet |
325, broadband |
Unlike modern CCD cameras, vidicons produce an intinsic geometric distortion
that varies both with time and with the distribution of light within an
image. For this reason, the camera faceplate contained a grid of "reseau
markings" that
can be readily seen as dark spots in the raw images. Another quirk of vidicons
is that they build up a signal even when the shutter is closed. This is
referred to as "dark current." Recently, the Rings Node of NASA's
Planetary Data System has embarked upon a
project to calibrate and geometrically correct the Voyager images from
the Saturn encounter for these quirks. This project is ongoing, and the
calibrated and geometrically corrected data set has not yet (as of June
2007) passed peer review.
Saturn |
Saturn's rings |
The Saturn images are not being made
available here because
there are too
many (23,765) of them. A subset may
be made available
in the future, after
the data set has passed peer review. |
 |
Saturn's
rings (2,217 images) |
Large Moons |
Small Moons |
 |
Mimas
(78 images)
Closest approaches:
Voyager 1: 88,440 km
Voyager 2: 309,930 km |
 |
Unnamed Moons
(Mostly moons unnamed
as of the Voyager
encounters; includes
images of many of
the
named moons below) |
 |
Enceladus
(87
images)
Closest approaches:
Voyager 1: 202,040 km
Voyager 2: 87,010 km |
 |
Calypso
(11 images)
Closest approaches:
Voyager 1: 432,000 km
Voyager 2: 151,590 km |
 |
Tethys
(106 images)
Closest approaches:
Voyager 1: 415,670 km
Voyager 2: 93,010 km |
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Epimetheus
(11
images)
Closest approaches:
Voyager 1: 121,000 km
Voyager 2: 147,000 km |
 |
Dione
(138 images)
Closest approaches:
Voyager 1: 161,520 km
Voyager 2: 502,310 km |
 |
Helene
(45
images)
Closest approaches:
Voyager 1: 237,000 km
Voyager 2: 314,090 km |
 |
Rhea
(233
images)
Closest approaches:
Voyager 1: 73,980 km
Voyager 2: 645,260 km |
 |
Janus
(7
images)
Closest approaches:
Voyager 1: 297,000 km
Voyager 2: 223,000 km |
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Titan
(925
images)
Closest approaches:
Voyager 1: 6,490 km
Voyager 2: 666,190 km |
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Pandora
(14
images)
Closest approaches:
Voyager 1: 270,000 km
Voyager 2: 107,000 km |
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Hyperion
(110
images)
Closest approaches:
Voyager 1: 880,440 km
Voyager 2: 431,370 km |
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Prometheus
(2
images)
Closest approaches:
Voyager 1: 300,000 km
Voyager 2: 247,000 km |
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Iapetus
(150
images)
Closest approaches:
Voyager 1: 2,470,000 km
Voyager 2: 908,680 km |
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Telesto
(2
images)
Closest approaches:
Voyager 1: 233,000 km
Voyager 2: 270,000 km |
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Phoebe
(305
images)
Closest approaches:
Voyager 1: 13,500,000 km
Voyager 2: 2,075,640 km |
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