Mro-launch qxp

the instrument for the university to provide to the mission. Additional information about

the instrument is available at hirise.lpl.arizona.edu .

The Compact Reconnaissance Imaging Spectrometer for Mars will extend the

search for water-related minerals on Mars by providing spectra that can be used to

identify the mineral composition of the surface. Each spectrum will indicate measure-

ments of the amount of light that Mars surface materials reflect or emit in many differ-

ent wavelengths, or colors, of visible and infrared light. Most minerals expected in the

Martian crust, and especially those formed by water-related processes, have charac-

teristic fingerprints in spectra of these wavelengths. The spectrometer will collect infor-

mation that could find key minerals in patches as small as a house, using resolution

about 10 times sharper than in any previous look at Mars in infrared wavelengths and

sharp enough to discover a deposit left by an individual hot spring or evaporated pond,

if such deposits exist. 

The imaging spectrometer will work both in targeted and survey modes. It will target a

few thousand selected areas for inspection at highest spatial resolution -- 18 meters

(60 feet) per pixel -- and spectral resolution -- 544 different wavelengths. It will spend

more of its time surveying the entire planet at resolutions of 100 to 200 meters (330 to

660 feet) per pixel in and about 70 different spectral channels ("colors"). The survey

will find candidate sites for targeted inspection. The search for water-related minerals

such as carbonates, clays and salts gets top priority for use of this instrument.

Researchers are planning observations of sites such as smooth interiors of ancient

craters that may have held lakes and volcanic regions that may have produced hot

springs. They will also use the spectrometer to monitor seasonal changes in dust and

ice particles suspended in the atmosphere. 

The spectrometer has a telescope with a 10-centimeter (4-inch) aperture and a 2-

degree field of view. That field of view produces images of swaths of Mars' surface

about 10 kilometers (6 miles) wide. The instrument records the intensities of light in a

range of wavelengths from 370 nanometers (violet) to 3,940 nanometers (near

infrared) and divides that range into bands as small as 6.55 nanometers wide. It is

mounted on a gimbal, which allows it to follow a target on the surface as the orbiter

passes overhead.

The principal investigator for the Compact Reconnaissance Imaging Spectrometer for

Mars is Dr. Scott Murchie of the Johns Hopkins University Applied Physics Laboratory,

Laurel, Md., which provided the instrument. Additional information about the spectrom-

eter is available at crism.jhuapl.edu .

The orbiter's Context Camera will return images of swaths 30 kilometers (18.6

miles) wide. Many of its images will be centered on the narrower swaths being imaged

simultaneously by the high-resolution camera or the imaging spectrometer, or both. It

has a resolution capable of showing the shapes of features smaller than a tennis court. 

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This instrument will perform roles in both the regional-survey and the targeted-observa-

tion modes. For the targeted mode, it will provide broad yet detailed visual context for

interpreting observations by co-targeted instruments. Over the course of the primary

science mission, it will produce regional surveys of about 15 percent of the planet's

surface in relatively high resolution, which is expected to identify many targets for more

detailed inspection. However, its ability to provide extended area imaging at moderate-

ly high resolution will enable it to examine the stratigraphy and morphology of many

regional features and thus directly address key questions about changes in the Martian

surface over geologic time and the roles that water and wind have played in these

changes.

The camera is monochromatic and will produce black-and-white images. It has a single

passband for visible light at 500 to 700 nanometers). It has a 5.8-degree field of view

recorded onto a linear array 5,000 pixels wide, providing a resolution of 6 meters (20

feet) per pixel. 

Malin Space Science Systems, San Diego, Calif., provided the Context Camera for this

mission. Dr. Michael Malin is team leader for use of the instrument.

Mars Color Imager will produce daily global views to monitor changes in the atmos-

phere and on the surface. It can produce color images and see in ultraviolet wave-

lengths. Each image through the extremely wide-angle lens will catch the planet from

horizon to horizon with spatial resolution selectable from one kilometer (0.6 mile) per

pixel to 10 kilometers (6 miles) per pixel. 

As a key instrument for the mission's global-monitoring mode, Mars Color Imager will

provide daily weather maps of the entire planet and will track surface changes, such as

the seasonal growing and shrinking of polar frosts and the movement of dust at other

latitudes. Use of color filters will also enable researchers to identify the composition of

clouds, which may be water ice, carbon-dioxide ice, or dust. Researchers will make

use of the camera's ultraviolet filters to examine variations in the amount of ozone in

the atmosphere. Ozone serves as a reverse indicator about water in Mars' atmos-

phere. Where there's more water, there's less ozone, and vice versa.

Mars Color Imager is essentially a copy of a camera that flew on the lost Mars Climate

Orbiter mission. However the instrument on Mars Reconnaissance Orbiter has a wider

fisheye lens to compensate for planned spacecraft rolls needed to target specific sites

on Mars with other instruments. The camera has a field of view of 180 degrees. Its

seven filters include five centered in visible-light wavelengths (425, 550, 600, 650 and

725 nanometers) and two in ultraviolet wavelengths (250 and 320 nanometers). 

Malin Space Science Systems, San Diego, Calif., provided this instrument, and Dr.

Michael Malin of that company is the principal investigator for it. 

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