An Article In Meteorite-Times Magazine
by Martin Horejsi of  Martin Horejsi's Meteorite and Tektite Books


Meteorites and Space Exploration

There are dozens of active spacecraft flying around various parts of our solar system. In addition, there are many more yet to be launched. Here is a short-listing of current and future space missions that May have a direct impact to meteorite science.

Some missions are sample-return missions that will provide actual physical material that can be studied in the laboratory. Others provide scientific observations that will shed light on various aspects of the very meteorites gracing our collections.

The following list contains material taken directly from the Internet site for that mission. The URL for the mission is at the end of each entry. For a complete listing of all past, present and future space missions involving NASA can be found at the Office of Space Science at:

Another general Internet site of interest is the Solar System page at the Jet Propultion Laboratory. This site provides an interactive connection between spacecraft and planets, as well as a few interesting tidbits about each planet.

Missions Currently Operating:

Stardust is the first U.S. space mission dedicated solely to the exploration of a comet, and the first robotic mission designed to return extraterrestrial material from outside the orbit of the Moon. The Stardust spacecraft was launched on February 7, 1999, from Cape Canaveral Air Station, Florida, aboard a Delta II rocket. The primary goal of Stardust is to collect dust and carbon-based samples during its closest encounter with Comet Wild 2 - pronounced "Vilt 2" after the name of its Swiss discoverer - is a rendezvous scheduled to take place in January 2004, after nearly four years of space travel. Additionally, the Stardust spacecraft will bring back samples of interstellar dust, including recently discovered dust streaming into our Solar System from the direction of Sagittarius. These materials are believed to consist of ancient pre-solar interstellar grains and nebular that include remnants from the formation of the Solar System. Analysis of such fascinating celestial specks is expected to yield important insights into the evolution of the Sun its planets and possibly even the origin of life itself.

Genesis is a sample-return mission to collect solar wind. Here are the main Genesis Mission Science Objectives:
*To obtain precise measures of solar isotopic abundances.
Genesis will measure isotopic compositions of oxygen, nitrogen, and noble gases. These data will enable scientists to better understand the isotopic variations in meteorites, comets, lunar samples, and planetary atmospheres.)
*To obtain greatly improved measures of solar elemental abundances.
*To provide a reservoir of solar matter for 21st century science research, eliminating the need for future solar wind sample return mission.

Missions in Development:

Mars Exploration Rover Missions (MERs)
NASA's twin robot geologists, the Mars Exploration Rovers, will launch toward Mars in 2003 in search of answers about the history of water on Mars. Primary among the mission's scientific goals is to search for and characterize a wide range of rocks and soils that hold clues to past water activity on Mars. The spacecraft will be targeted to sites that appear to have been affected by liquid water in the past.

Deep Impact will be the first mission to make a spectacular football stadium-sized crater 7-15 stories deep into a speeding comet. Dramatic images from both the flyby spacecraft and the impactor will be sent back to distant Earth as data in near-real time. These first ever views deep beneath a comet's surface, and additional scientific measurements will provide clues to the formation of the solar system. Amateur astronomers will combine efforts with astronomers at larger telescopes to offer the public an earth-based look at this incredible July 2005 encounter with a comet.

MESSENGER will peel back Mercury's veil of mystery. MESSENGER is a ME rcury Surface, Space EN vironment, GE ochemistry, and Ranging mission to orbit Mercury following two reconnaissance flybys. MESSENGER will investigate key science questions using an optimized set of miniaturized instruments: What is the origin of Mercury's high density? What are the composition and structure of its crust? What is Mercury's tectonic history, and is its surface shaped by volcanism? What are the characteristics of the thin atmosphere and miniature magnetosphere? And what is the nature of the mysterious polar caps?

Rosetta will study the nucleus of comet Wirtanen and its environment in great detail for a period of nearly two years, the near-nucleus phase starting at a heliocentric distance of about 3.25 AU, with far observation activities leading ultimately to close observation (from about one km distance).

Missions Under Study:

Dawn's goal is to characterize the conditions and processes of the solar system's earliest epoch by investigating in detail two of the largest protoplanets remaining intact since their formations. Ceres and Vesta reside in the extensive zone between Mars and Jupiter together with many other smaller bodies, called the asteroid belt. Each has followed a very different evolutionary path constrained by the diversity of processes that operated during the first few million years of solar system evolution.

Sample Collection for Investigation of Mars (SCIM)
SCIM, Sample Collection for Investigation of Mars, has been selected by NASA as a finalist in its competition for low-cost Mars Scout missions. During its high-speed encounter, SCIM will collect samples of Martian dust and atmosphere and return them to Earth. By allowing scientists worldwide to study these samples in their laboratories, SCIM will help to unlock the secrets of Mars water, climate, and geologic evolution.

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