This was an interesting article I found on another forum I visit but it wasn't receiving much attention for what I personally think is one of the most important scientific breakthroughs in history.
NASA-funded researchers have evidence that some building blocks of DNA, the molecule that carries the genetic instructions for life, found in meteorites were likely created in space. The research gives support to the theory that a "kit" of ready-made parts created in space and delivered to Earth by meteorite and comet impacts assisted the origin of life.
"People have been discovering components of DNA in meteorites since the 1960's, but researchers were unsure whether they were really created in space or if instead they came from contamination by terrestrial life," said Dr. Michael Callahan of NASA's Goddard Space Flight Center, Greenbelt, Md. "For the first time, we have three lines of evidence that together give us confidence these DNA building blocks actually were created in space." Callahan is lead author of a paper on the discovery appearing in Proceedings of the National Academy of Sciences of the United States of America.
This has some huge implications. If this is correct than the chances we are alone in the Universe just dropped to virtually nothing. This could also mean that we share the same basic DNA structure or building blocks as a lot of other life in the Universe.
Basically it seems like they think these objects floating out in cold dead space have the capacity to act as a "chemical factory" and produce the nucleobases which are responsible for life on Earth.
"In fact, there seems to be a 'goldilocks' class of meteorite, the so-called CM2 meteorites, where conditions are just right to make more of these molecules," adds Callahan.
If you consult the Wikipedia page for Panspermia
you will see it offers a slightly different explanation. The chemicals they carry could be the result of collisions between planets that harbor life.
Panspermia (Greek: πανσπερμία from πᾶς/πᾶν (pas/pan) "all" and σπέρμα (sperma) "seed") is the hypothesis that life exists throughout the Universe, distributed by meteoroids, asteroids and planetoids.
Panspermia proposes that life that can survive the effects of space, such as extremophile bacteria, become trapped in debris that is ejected into space after collisions between planets that harbor life and Small Solar System Bodies (SSSB). Bacteria may travel dormant for an extended amount of time before colliding randomly with other planets or intermingling with protoplanetary disks. If met with ideal conditions on a new planets' surfaces, the bacteria become active and the process of evolution begins. Panspermia is not meant to address how life began, just the method that may cause its sustenance.