Sampling Meteor Dust Particles
When a meteor shower from an asteroid or comet occurs, particles of all sizes shower upon Earth. Large ones burn up in the atmosphere or larger ones actually hit the Earth. The challenge is to catch particles before they burn up to analyze their composition. NASA's interest is based on expanding the data base of knowledge of what these bodies are made of. For SETI, there is a theory called Panspermia, where the premise is that life is seeded through out the universe by passing objects that are pre-solar system. Finding particles called carbonaceous chondrites is the goal. They contain carbon compounds, hydrocarbons, alcohols, amino acids, and water- the building blocks of life as theorized! What a fascinating theory.
With the success of the two THOR launches, we are hopeful both NASA and SETI will want to have more launches with collection devices so they can validate their theory that life may indeed start from "seeding" of meteorite dust particles.
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A snapshot of the NASA website showing the Perseides orbit.
CARBONACEOUS CHONDRITE FROM METEOR
Because of their relatively porous nature and their resulting fragility, many would-be carbonaceous chondrite meteorites do not survive their passages through the atmosphere, or at the very least they lose a significant part of their mass during their passage. Of those that do survive and reach the ground, they are in general quite susceptible to weathering and thus do not remain intact for very long. Although some have been found that apparently fell to the ground a long time ago – generally in pristine environments like Antarctica where erosional effects are minimized – most carbonaceous chondrites that have been well studied have come from observed meteorite falls.
SOME TECHNICAL AND SCIENTIFIC INFORMATION REGARDING THE ORIGIN OF LIFE THEORY
Amino acids and other highly sensitive compounds may survive in carbonaceous meteorites for many billion years (Engel and Macko, 1997), and hydrocarbon biomarkers have endured in sedimentary rocks with little alteration for as long as 1.7 billion years. The carbon upon which our life is based could have originated from a number of sources. Carbonaceous material would have accreted together with the planetesimals that formed the planet (see section 1.2 for a summary): there is a wide range of carbonaceous particles in the interstellar medium ranging from amorphous carbon to polycyclic aromatic hydrocarbons(PAHs), and even more complex molecules such as fullerenes (ball-shaped molecules composed of 60, 70 and more C atoms arranged in rings); these molecules and, additionally, C2H6, and CO+ occur in comets, whereas carbonaceous meteorites contain a large variety of organic particles including amino acids that do not occur on Earth (Ehrenfreund and Menten, 2002). Carbon on the Earth could have come from the original volatile-containing planetesimals that collided to form the Earth (Drake and Richter, 2002). It could also have had an extraterrestrial origin. The delivery of extraterrestrial organic matter is particularly interesting since the mildly reducing conditions of the early Earth (Kasting, 1993; see also section 5.2) would not have been conducive to the production of prebiotically-important molecules, as produced in vitro by Miller (1953). After the consolidation of the Earth (and formation of the Moon, probably by collision with a Marssized planet, Canup and Asphaug, 2001; see, however, section 5.9), organic molecules would have continued to have been imported by comets, meteorites/asteroids, micrometeorites and cosmic dust (Maurette et al., 2000). This importation is on-going but the flux was much greater in the first 500–600 My of Earth history, during the heavy bombardment period. Other potential sources of prebiotically-important organic molecules include hydrothermal vent environments (Shock, 1992) and impact (sections 1.3 and 1.4) synthesis (Blank et al., 2002).