Follow this link to skip to the main content

VIMS

VIMS

Map of Titan in Infrared
Map of Titan in Infrared


There are a lot of things that our eyes cannot see; just ask those who operate a spectrometer -- an optical instrument that splits the light received from objects into its component wavelengths. Since each chemical has a unique spectral signature, they can be identified this way.

The Visible and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft is made up of two cameras in one: one is used to measure visible wavelengths, the other infrared. Combined, the two cameras gather a lot of information on the composition of moon surfaces, the rings, and the atmospheres of Saturn and Titan.

"Our instrument measures the characteristic colors of the many materials that make up planetary surfaces and atmospheres: rocks, ices -- such as water, ammonia, methane -- and organic compounds," says Dr. Bonnie J. Buratti, VIMS Investigation Scientist. "VIMS data makes it possible to know what surfaces and atmospheres are made up of."

Infrared Image of Titan Volcano
Infrared Image of Titan Volcano


The instrument detects signals from a large range of wavelengths -- three octaves -- and it gathers 99 percent of radiation that is reflected from the Sun to a surface. Soon after Cassini reached Saturn, the instrument sent home valuable information.

"Data from VIMS allowed us to discover an ice volcano on Titan and the presence of fresh ice at the 'tiger stripes' on the moon Enceladus," Buratti says. "We are looking forward to the many upcoming flybys of Titan and of the moon Rhea. I am excited about Rhea because I'd like to see if it's an older version of Enceladus -- like Dione -- or something completely different."

The instrument is designed to measure reflected and emitted radiation from atmospheres, rings and surfaces over 352 contiguous wavelengths from 0.35 to 5.1 micrometers. It will also help determine the compositions, temperatures and structures of these objects.

Geologic Map of Titan Volcano
Geologic Map of Titan Volcano


With VIMS, scientists are also conducting a long-term study of cloud movement and morphology in the Saturn system to determine the planet's weather patterns. VIMS also observes the sunlight and starlight that pass through the rings to learn more about ring structure.

The VIMS team is spread across the Atlantic.

"We are very international! Most of our members are from Europe -- France, Italy and Germany," Buratti says.

For more information, read the engineering technical write-up or visit the science team's Web site: http://wwwvims.lpl.arizona.edu/.

At a Glance

Visible and Infrared Mapping Spectrometer (VIMS) on the spacecraft
VIMS on the Cassini Spacecraft


VIMS includes a pair of imaging grating spectrometers that are designed to measure reflected and emitted radiation from atmospheres, rings and surfaces to determine their compositions, temperatures and structures.

  • Visible Channel [VIMS-V] (0.35 to 1.07 µm [96 channels]; 32x32 mrad field of view)
  • Infrared Channel [VIMS-IR] (0.85 to 5.1 µm [256 channels]; 32x32 mrad field of view)
  • Mass (current best estimate) = 37.14 kg
  • Peak Operating Power (current best estimate) = 27.20 W
  • Average Operating Power (current best estimate) = 21.83 W
  • Peak Data Rate (current best estimate) = 182.784 kilobits/sec
  • Dimensions (approximate) = 78 cm x 76 cm x 55 cm