It has long been hypothesized that comets are one of the main carriers of DNA/RNA and complex molecules of life inside the Solar System.

Surely 67P/Rosetta offers an important opportunity that ESA must seize – and on THIS mission! NOT on a new mission sometime in the future.

When Chandra Wickramasinghe attended early design meetings on Rosetta as a principal investigator, it was well known that he brought the view that “life detection” experiments should be carried on each of the two parts of the spacecraft.

But in those days, just 13 years ago, the field of astrobiology was of limited respectability to the astronomers, geologists, chemists and physicists who dominated the focus of the early team.

Since the 2013 consciousness change with the Kepler Mission breakthrough discoveries and announcements, current probabilities calculate that every star in the galaxy most likely has at least one exoplanet and perhaps a large number have an exoplanet  in their “Goldilocks zone”.

This was strong evidence for the “life is a cosmic phenomenon” philosophy of  Hoyle and Wickramasinghe. NASA astrobiologist Dr. Chris McKay, is often heard confirming his adoption of this theory.

So have the local Panspermia processes already seeded most of the inner Solar System with desiccated viruses, bacteria and algae?

I believe so.

Contamination

As for “contamination by humans”, we know over 500 different species of bacteria can be found in a healthy human mouth, with at least ten times that many viruses. An experiment with a probiotic yoghurt counted the number of bacteria exchanged in a 10 second “intimate” kiss – and found a whopping 80 million passed from tongue to tongue.

If that surprises you, did you know every whale on the planet excretes 10¹³ viruses per day in their feces.

No wonder the Space Station is considered contaminated. MARS itself has likely already been contaminated, even without humans taking our biome with us there on manned landings.

Dr. Chris McKay talks about asteroid collisions causing the ejection of microbes from a given planet with the possible transfer of life planet to planet, comet to planet. McKay is guiding us to learn that “the theory of Panspermia” is the best current guess for NASA’s short and long term planning.

This is the reason that “Seeking the Signs of Life” is “Difficult”, because not only are viruses very small and hard to remotely detect and classify, but even the larger particles such as bacteria and algae (diatoms) have similar (if not quite as challenging) difficulties.

At the Astrobiology conference in Sri Lanka last week, I talked with Professor Milton Wainwright, the biologist from Sheffield University in the UK. I was struck by his reaction when I pointed out new lens-free microscope technology which offers real-time bio-imaging (from a small and light device) which could allow much easier detection of viruses.

“Our tests in the stratosphere have been focused on larger particles typically algae (aka plankton; diatoms). The benefit of our focusing on these larger-sized particles has been that they are much less likely to have been lifted from the surface of Earth. Plus the particles we are finding are spectacularly interesting”, Professor Milton Wainwright .

But comets as carriers? Many of us will recall reading that Sir Arthur C. Clark was most impressed with the Hoyle-Wickramasinghe Model but cautioned us that we would have to wait for the return of the short-period comet, Halley, in 2061, to confirm the theory.

Little did Clark know how quickly humans would be able to dance around the solar system jumping from one comet to another, taking samples and transmitting the results back to our control centres on Earth!

Chandra left the Rosetta team in frustration, around 2002, saddened that his advice seemed to have been ignored. But it now seems that many quietly heeded his input and raised their game. So we actually have a very sophisticated set of “seeds of life” detection instruments on Rosetta and Philae.

We do NOT have an instrument that actually detects a “moving” microbe. At least this is not overtly stated (MIDAS is very close). But the experiments on Philae and Rosetta together detect almost everything else you might wish to seek.

Chandra has been particularly intrigued with the MIDAS experiment which is operating at the virus–size level. It might not be able to deliver conclusive proof of microbes on this voyage, but this technology augurs well for the next comet visit.

Long Period Comets

My own particular request is for us to visit a long-period comet –similar to ISON 2 years ago. Unlike 67P, which orbits over just 8 years and in the plane of the Galaxy, the long-period comets have orbits of over 100,000 years and might well come in from adjacent stars. They also come in at a steep angle to the plane of the Galaxy.

The Solar System is at an angle to the plane of the galactic disk. This is almost certainly because the Solar system is not from the Milky Way. Rather it is now believed to be part of the Sagittarius Galaxy passing through the Milky Way. I believe the long period comets, if they come in from an adjacent star, or even from the Oort Cloud, can come in at any angle to the ecliptic – ie to the plane of the solar system. Whereas short period comets are always IN the plane of the solar system.

Typically the bulk of the long period comets, have been moving in the plane of the  Milky Way (at the constant angle to the solar system). So they usually come in at a steep angle.

I believe it is highly likely we will confirm life in the short period comets – as Hoyle and Wickramasinghe predicted. But finding life in a long-period comet would be even more significant, as this would be life not just from another star system but even from another galaxy – the Milky Way.

According to Wickramasinghe’s predictions, the whole Galaxy is a homogenized life pool, so it would be an exciting experiment to seek and discover life in a long-period comet, and to compare any of its RNA/DNA with our known Solar System RNA/DNA. Although we might predict differences in the life-form roots from the two separate galaxies, the inter-galactic contamination has been going on for a very long time, so it is unlikely there is any major differences between life in the two galaxies.

iBOL

I have recently learned much about the iBOL Project (International Barcode of Life – DNA classification project) and believe this will become very important. I will cover this in my next “Letter from Canada”.

Bill Smith

At AbReCon 2015

Astrobiology Research Conference

University of Peradeniya, Sri Lanka

21-23 August 2015