2003 Mars
Exploration Rovers Athena Science Payload -- Mini-Thermal Emission Spectrometer
(Mini-TES) Frequently Asked Questions

  1. What is Mini-TES?
  2. Why are we exploring Mars?
  3. Why is the search for water on Mars so important?
  4. How will Mini-TES help determine if Mars once had water?
  5. What instruments besides mini-TES are on the landers?
  6. Why is NASA landing in Gusev crater?
  7. Why is NASA landing in Meridiani Planum?
  8. How did Mini-TES get to Mars?
  9. Where are Mini-TES and the Spirit rover now?
  10. Where are Mini-TES and the Opportunity rover now?
  11. What else do scientists already know about Gusev crater?

  1. Q. What is Mini-TES?

    A: The Miniature Thermal Emission Spectrometer (Mini-TES) will provide remote measurements of mineralogy and thermophysical properties of the landscape around the Mars Exploration Rovers, and guide the Rovers to key targets for detailed investigation by other Rover experiments.

    Mini-TES collects high-resolution infrared spectra that will help identify the mineralogy of all geologic materials including silicates, carbonates, sulfates, phosphates, oxides and hydroxides. Mini-TES will also measure the lower atmospheric boundary layer and provide information on suspended dust, water ice, and water vapor opacity.

    The Mini-TES is a miniaturized version of the Thermal Emission Spectrometer (TES) built by Arizona State University and Raytheon Santa Barbara Remote Sensing for the Mars Observer and Mars Global Surveyor missions.

  2. Q: Why are we exploring Mars?

    A: Mars has a fascinating and diverse terrain including polar ice caps, dry river valleys, volcanoes, canyons and craters. While we’ve already visited the planet several times before, there is still much more to learn. Of all the planets in our solar system, Mars is perhaps the most earthlike, and it may be the best location to search for extraterrestrial life.

  3. Q: Why is the search for water on Mars so important?

    The main scientific objective for both rovers is to investigate Martian geologic history and understand what role water played in it.

    Water is a basic requirement for the origin and continued existence of life. Determining how much -- and how long liquid water existed on the planet’s surface are fundamental questions in our search for evidence of past or present life on Mars.

  4. Q: How will mini-TES help determine if Mars once had water?

    A: The mini-TES instrument is a 167 channel, high resolution, infrared spectrometer that can directly identify minerals around the landing sites.

    In Gusev Crater, mini-TES will look for minerals like carbonates and sulfates that form only in the presence of water. Finding them will provide strong evidence that Gusev was once a lake.

    In Meridiani Planum, mini-TES will help determine how the mineral gray hematite formed. On earth, gray hematite usually forms in the presence of water. At Meridiani, mini-TES will search for the minerals goethite and magnetite. If goethite is found, the area almost certainly once had water. If goethite is not present but magnetite is, the hematite formed under dry conditions.

  5. Q: What instruments besides mini-TES are on the landers?

    A: Each lander will deploy a solar powered Mars Exploration Rover vehicle that will explore its surroundings for several months using a variety of scientific tools.

    These include a color stereo camera, a microscope, and three unique spectrometers that will determine the mineral and elemental composition of the rocks and soils.

    The color camera will search for layered rock deposits and other past evidence of flowing or standing water.

    The rover’s microscope will examine the granular structure within the area’s rocks and soils. Water-borne particles have a smoother, rounded appearance, while fresh volcanic ash has sharper, angular grains.

  6. Q: Why is NASA landing in Gusev Crater?

    A: While some areas, such as rugged canyon floors or volcano calderas might be exciting to explore, they’re just too difficult and dangerous to land on.

    The landing sites chosen for the Rovers provide the right combination of safety and interesting science.

    Some scientists believe water from a large basin lying farther south turned Gusev into a lake that persisted for millions of years. A large channel called Ma’adim Vallis may once have carried water into the lake. Where the channel intersects the crater’s southern rim, we see eroded terrain that may be ancient river delta deposits.

  7. Q: Why is NASA landing in Meridiani Planum?

    A: While some areas, such as rugged canyon floors or volcano calderas might be exciting to explore, they’re just too difficult and dangerous to land on.

    The landing sites chosen for the Rovers provide the right combination of safety and interesting science.

    The landing site falls within an area equivalent in size to the state of Ohio that displays the spectral signature of the iron oxide mineral gray hematite.

    This was a major discovery of the Thermal Emission Spectrometer instrument, because on earth, hematite usually forms in conjunction with water.

  8. Q: How did Mini-TES get to Mars?

    A: On June 10th, 2003 NASA launched a Delta 2 rocket carrying Spirit --the first of two Mars Exploration Rovers on a mission to the Red Planet.

    27 days later, on July 7th, Spirit’s robot twin, named Opportunity, was launched in pursuit. It will take both spacecraft about 208 days to make the 300 million mile journey to Mars.

    Each spacecraft carries a rover with its own mini-TES instrument on board.

    After traveling through space for nearly seven months, Spirit arrived at Mars and touched down just south of the equator inside the 90-mile wide in Gusev Crater on January 3rd 2004 (PST). Opportunity is scheduled to land on January 24th 2004 in Meridiani Planum at a point 2 degrees south of the Martian equator.

  9. Q: Where are Mini-TES and the Spirit rover now?

    A: We believe Spirit is in the area pointed to by the arrow in this image.

  10. Q: Where are Mini-TES and the Opportunity rover now?

    A: Opportunity is currently approaching Mars, and is expected to land on January 24.

  11. Q: What else do scientists already know about Gusev Crater?

    A: Gusev is a windswept, 90-mile wide impact crater that formed between 3 and 4 billion years ago. The Mars Orbiter Laser Altimeter (MOLA) instrument has compiled topographic maps of the area that show the crater is only a little over 1 mile deep.

    We know a 2-mile thick layer of material covers Gusev’s floor, because a fresh impact of this size would be much deeper. Scientists are unsure if the crater floor deposits were transported by water from the Ma’adim Vallis channel lying to the south, or if the nearby volcano Apollinaris Patera filled the crater with ash.