Did Comets and Asteroids Make Life on Earth (and Mars?) Possible?

"Panspermia Goes Primordial

Most scientists have long believed that life on Earth began as a "primordial soup" in a lake or pond some four billion years ago. According to this theory, chemicals from the atmosphere combined with some form of energy necessary to make amino acids—the building blocks of proteins—to create the first primitive organisms, kicking off the evolution of Earth's species.

But the primordial soup theory is being increasingly disputed. Many geophysicists now say the Earth did not have enough gases, like ammonia and methane, from which organic material like amino acids could be produced.

Instead, a growing cadre of scientists believes the organic material needed to create life may not have been produced on Earth, but was instead brought here by comets. The newly formed Earth was likely subjected to a fierce bombardment of comets four billion years ago. These comets may have brought with them the organic compounds that later evolved into living matter.

According to the most radical theory, known as "panspermia," life in a ready-made form is ubiquitous in the galaxy and is brought by comets to new planets. Few scientists subscribe to this hypothesis, however. "


Robert Clark,

Could I have you repost the article about life in asteroids and comets that you posted earlier? Thanks!



"Scientists discover possible microbe from space

November 24, 2000
Web posted at: 1:51 PM EST (1851 GMT)

By Richard Stenger
CNN.com Writer

(CNN) -- An international team of scientists has recovered microorganisms in the upper reaches of the atmosphere that could have originated from outer space, a participant in the study said Friday.

The living bacteria, plucked from an altitude of 10 miles (16 km) or higher by a scientific balloon, could have been deposited in terrestrial airspace by a passing comet, according to the researchers.

The microorganisms are unlike any known on Earth, but the astrobiologists "want to keep the details under wraps until they are absolutely convinced that these are extraterrestrial," said study participant Chandra Wickramasinghe, a noted scientist at Cardiff University in Wales. "




In nature, images repeat. We can look at an atom and see a solar system.
The image of a comet striking the Earth brings to mind the image of a sperm and an egg.


That's an excellent contribution Mars. I had no idea anything could live at that height. There's no liquid water up there, that's for sure.

Craig Venter, the man who spearheaded the private sequencing of the human genome at Celera, is on record as believing that panspermia is the reality of life in the universe. This was part of a recent NY Times article where many prominent people (researchers, artists, etc) were asked to describe something they believed but could not prove.

Panspermia is really fascinating - the panspermia.org guys propose a further advance - "Cosmic Ancestry" in that both extant life seeds formative planets and that single-cell organisms promote evolution among multicelled life by continuously making hostile swaps of DNA. They claim that something upward of 90% of the genome is from viral insertion of DNA, over the course of the last 500m years.

If true, panspermic life would give any world the opportunity to support life. This would probably be especially true in the outer solar system, as the gas giants and their moons soaked up most of the impacts during their formation. (Jupiter as "vaccuum cleaner") Wow, am I off-topic.

ObMars: panspermia, even local-spermia guarantees exchange of biological material througout the inner solar system. Impacts that result in material achieving escape velocity are frequent on a geologic timescale, the debris intersects between Earth, Mars and Venus on the scale of thousands to millions of years - we've been "swapping spit" between planets since the beginning. I'm not sure where life started, but we have bio-signs from Venus (chemical imbalance at 1-atmosphere altitude), possible methane and other signs from Mars. I think the time is approaching where life everywhere is going to become the accepted wisdom, again. Perhaps the whole universe breaths?


Marsman, I have been waiting patiently for Robert Clark to post, as per your request, prior to my posting on this thread.

Now I'm glad I waited to state, again, my belief in panspermia. I'm glad because these new posts are facinating!

Robert Clark, where are you?

Thanks for the comments, guys!

I will continue to do some more research on this topic.


The objection that life can't survive in space needs examination. A serious problem for Svante Arrhenius's theory in 1908 was that spores in empty space would be subject to radiation damage, especially in the vicinity of a star. In 1978, Hoyle and Wickramasinghe observe in Lifecloud (1) that if a cloud of bacterial matter were dense enough, the inner contents would be protected from radiation by the outer layers. Other scientists have recently observed that a coating of dust only half a micrometer thick would adequately protect a bacterium from ultraviolet radiation in space (2-4).

Hoyle and Wickramasinghe also discuss another means of space travel which solves the radiation problem: comets. The idea that comets could bring to Earth the ingredients for life is not completely new. Among others, Isaac Newton endorsed it. "Newton considered the continual arrival of cometary material to be essential for life on Earth" (5).

Some Basic Facts about Comets

Comets, as astronomer Fred Whipple figured out, are made largely of ice. Much of the ice in comets is frozen water, but ices of other compounds such as carbon monoxide and carbon dioxide are also present. And comets contain, we have recently learned, a large amount of more complex organic compounds. These organic compounds may be limited to a mixture of molecules such as the original Miller - Urey experiment was able to produce, or they may be even more closely related to life; we can't be sure from here, yet. In the interior of a comet, under layers of opaque organic material, viable cells would be shielded from radiation. Of course, freezing slows or stops metabolism, so cells could exist there in suspended animation. "





This is honestly the best contribution to the blog in awhile. If true, it could help explain a lot. I'd like to know what sustains these things up so high in the atmosphere.

Just think about it, they've found these curious micro organisms in the earth's crust living on volcanic glass, and now this. It's top to bottom here, life is everywhere no matter what!

another quick thought on panspermia:

there was an article a while ago (on space.com, IIRC) that discussed the possibility of freeze-dried DNA being recoverable from the moon. This implies that, with the right genetic tech, we will some day be able to read a "library" of frozen DNA that amounts to Earth's whole biological history. Trilobites for supper?


Did a Comet Bring SARS to Earth?

"Severe Acute Respiratory Syndrome (SARS) is described by the World Health Organization (WHO) as an atypical pneumonia of unknown origin, first recognized at the end of February 2003.

Medical researchers have described the bug that causes SARS as a coronavirus.

WHO is coordinating an international investigation with the Global Outbreak Alert and Response Network and is providing epidemiological, clinical and logistical support to health authorities in affected countries.

Comets in the picture? Some space biologists have suggested in recent years that comets may contain organic chemicals and even water."



"The lethal wave of influenza in 1918-19... was first detected on the same day in Boston and Bombay. Yet in spreading within the United States it took three weeks to go from Boston to New York. — Fred Hoyle and Chandra Wickramasinghe (1)

One of Hoyle and Wickramasinghe's more controversial claims is that influenza outbreaks are often caused by newly arriving viruses from space. Among several lines of evidence, they noticed that the worst flu epidemics coincide with peaks in the eleven-year cycle of sunspot activity. When an unusually vigorous flu epidemic again matched the pattern in January, 2000, they renewed the story in Current Science, a weekly journal of the Indian Academy of Sciences. In London, The Guardian covered the story (2), and a controversy erupted. Here is some of the ensuing discussion, 21-26 January 2000."


"New genetic programs in Darwinism and strong panspermia

The history of life on Earth is characterized by the appearance of species with new organs, parts, tissues, systems and capabilities. Examples of these new features include the first appearance of photosynthesis, oxygen metabolism, multicellularity, cell specialization, sexual reproduction, locomotion, digestive systems, circulatory systems, nervous systems, hard shells, lungs, limbs, bones, scales, feathers, skin, hair, wings, eyes, ears, etc. Such new features are made possible by new genetic programs. The genetic programs for photosynthesis and oxygen metabolism, for example, are well-studied. We would like to know where new genetic programs come from.


What about the big bang? We are aware of the argument that genetic programs must originate at some time. The foundation for this argument is the big bang. However, if new genetic programs do originate as Darwinism prescribes, the process would have continued at least until the emergence of the human species. It should be possible to obtain evidence of this recent process. If the evidence is obtained, the existing paradigm would get welcome confirmation. If direct evidence is not obtained after sustained effort, that result would also contribute to science.

The situation was analogous in the 1880s, when Al Michelson sought direct evidence of the luminiferous aether. Almost no one doubted its existence. The highly successful wave theory of light seemed to require it. The definitive experiment was performed by Michelson and Ed Morely, and reported in 1887. When no evidence of the aether was found, a major scientific advance ensued. "


"21 Feb 2005: Duplication Makes A New Primate Gene

A new primate gene has been analyzed by German molecular biologists (1). Comparing sequences from the human, mouse, rat, roundworm, fruitfly, mosquito and pufferfish genomes, the biologists identified 22 genes that were present as only single-copy orthologs in all but humans, where they have at least one paralog. These genes were most likely duplicated after the evolutionary split between the human and mouse lineages, they reasoned. Among the 22 duplicated genes, they named the most interesting one RGP. The human version of it has eight family members, each predicted to encode proteins of more than 1700 amino acids (big ones). Important functions for them are likely, but not precisely known. "



Link to the last article in Reply 9:


"In every direction astronomers look with telescopes, they see starlight dimmed by bacteria sized dust between the stars. A size of about a thousandth of a millimeter across is the best guess at the size of interstellar dust due to the ability of particles this size to scatter starlight.

In 1978 Wickramasinghe conducted experiments in the laboratory that showed infrared light passed through dried bacteria was absorbed in a characteristic way between 2 and 4 micrometers. He then confirmed that the infrared spectrum of GC-IRS7 (a powerful infrared light source from the center of the Milky Way galaxy) matched this absorption. This may mean that space is full of dried bacteria, but how can this be? "


"It is believed that orbiting our Sun beyond the farthest planet and extending a fair distance out to the nearest star, there are about 100 billion comets in a vast cloud known as the Oort Cloud.

If most of the other two hundred billion stars in our galaxy also have clouds of comets, there could be a mass 10 million times the mass of the Sun, enough material to feed the proposed amount of interstellar bacteria.

Collisions occasionally bump a comet out of the Oort cloud and send it into our solar system. As they near the sun, they melt and eject a multimillion mile long tail of debris. Halley's Comet, for example, visits the inner solar system every seventy six years.

During it's last visit, space probes revealed that the particles ejected were the same size as interstellar dust grains and that they absorbed light in the same way. As it turns out, pressure from the solar wind will push dead bacteria right out of the solar system. Comets, may be icy dust balls the size of small mountains. It is believed they form in the later stages of the collapse of a cloud of interstellar gas and dust which shrinks together under its own gravity.

If bacteria are not destroyed by space they could be incorporated into comets when the comets form."




Perhaps the life force itself is a natural phenomenon. :wink:

i'd never read of Dr. Wickramasinghe's infrared filtering tests, that is very interesting. I wonder if any research has been done into detecting chlorophyll in interstellar space? There have been PHAs (complex "aromatic" polymers) detected in deep space. Bacteria in stasis throughout interstellar space makes more sense, to me, than a sterile cosmos. Life is incredibly tough, practically every environment on, in, under and above Earth is inhabited.

For most of history, life everywhere has been assumed. It's only been a narrow window in the latter 20th and early 21st Century that "life nowhere" has become the default hypothesis. In ancient India and China, it was taught that there were other Buddhas out in the galaxy and in previous stellar epochs.


Some news on the comet findings from the Deep Impact spacecraft:

"Although comets form at the frigid edges of the solar system, they appear somehow to contain minerals that form only in the presence of liquid water, and at much warmer temperatures, scientists are reporting today.


Arrows on a composite image of the comet Tempel 1 point to two areas where the surface is smooth instead of spotted with depressions.

On July 4, as planned, part of the Deep Impact spacecraft - essentially an 820-pound, washing machine-size bullet - slammed into the comet Tempel 1 at 23,000 miles an hour. The collision tossed up thousands of tons of ice and dust from the comet that were observed by telescopes on Earth as well as small flotilla of spacecraft.

One of the observers was the Spitzer Space Telescope, a NASA mission that takes pictures in the infrared part of the spectrum. In the burst of light after the collision, Spitzer detected specific colors of infrared light that indicated that Tempel 1 contained clays and carbonates, the minerals of limestone and seashells.

Clays and carbonates both require liquid water to form.

"How do clays and carbonates form in frozen comets where there isn't liquid water?" said Carey M. Lisse, a research scientist at the Applied Physics Laboratory at Johns Hopkins University who is presenting the Spitzer data today at a meeting of the Division for Planetary Sciences in Cambridge, England. "Nobody expected this."... "


IMO, the discovery of clays and carbonates tends to further support a Panspermia hypothesis for the widespread presence of microbial life throughout the solar system and universe (including Mars).



If carbon, nitrogen, oxygen, and hydrogen (common in space) are a large part of commets then the earth would also be a large part of those atoms. comets and planets formed from the same solar system. comets would just bring in stuff from further out in the solar system.

star systems do approach each other and thus can possibly spread life from one system to the next.

microbes steal DNA from the environment. So innert DNA from space could be incorporated into earth bacteria. So the lines between planetary DNA could be blurred.

Virus's are very specific. a virus cannot wander in from space and attack us. Even avian flu (and most other earth microbes) has trouble attacking humans.

r_lewis brought up an interesting point and idea about glaciers.






Have you seen this NASA photo of a “ fluffy comet-like object ” entering Earth’s atmosphere ? There was speculation that these were a major contributor of water and other “ stuff ” to our planet: see


The word Influenza comes from the 19th century belief that it was due to the influence of comets (l'influenza delle comete). Influenza is an Italian word meaning influence. (In case you didn't know)

As Karl pointed out, the constituents of Ort Cloud comets accreted from the same cloud of matter as the rest of the Solar System. While gravity tended to sort out the material so that we have both gassy and rocky planets, undoubtedly all contain some of all the initial matter. And that matter was, at some point stars and planets. So the presense of minerals is to be expected. (Surely a nova does not return all matter to its elemental state!) So the panspermia idea does not reqire comet impacts: life forming materials would similarly be inclluded in our planet's formation.

However, I tend to believe that, because Nature is infinitely repetitive, that life spontaneously and inevitably develops wherever liquid water exists for a sufficient length of time. Such water becoming an ever more concentrated brine of chemicals that ultimately combine and recombine to finally form life. The self organization of a wide variety of molecules tends to support that idea.