One of the first papers released post Rosetta landing states “the Rosetta mission found that the comet’s water contains more of a hydrogen isotope called deuterium than water on Earth does”.
I have always thought that the source of water on earth was more likely long period Comets coming in from the Oort Cloud – or even in fact comets sling-shot in from an adjacent star.
To me this is no surprise. Just like Halley, 67P is a short period comet. But could its water have been ejected from MARS or VENUS? I must check the Rosetta paper and the hydrogen isotope ratio compared to that of water measured on other bodies such as on Mars.
The hydrogen isotope measure could be thoughts of as a fingerprint of the water’s source : ie from
another solar system planet
Asteroid (usually rock with minimal water)
Kuiper Belt Comet
Oort Cloud Comet
Adjacent Solar Systems
We still seem to be looking at evidence from an “earth centric” point of view. I expect one day we might discover the hydrogen isotope fingerprint ratio is ideal to determine the source star. I think though this will not be as useful a fingerprint as the DNA/Protein Fingerprint of the Viruses and Bacteria.
It was a paradigm shifting moment when in the summer of 2013 NASA’s Mars Curiosity Press Conference displayed the following backdrop :
So NASA was tacitly acknowledging that its umbrella mission was no longer the “Search for Water” but was now “Seeking the Signs of Life”. The Kepler Mission had caused a “consciousness change” in human expectations for life off the planet earth. With Kepler telling us that almost every star in the Milky Way Galaxy has at least one habitable planet, it was suddenly much more likely that “Life is a Cosmic Phenomenon” than that “Life started on Earth and is unique to Earth”.
By 2013 , the 2009 book “Virolution” by Frank Ryan was already having a profound impact on man’s understanding of “symbiosis” – the idea that the most successful life-forms across the earth and likely the Universe, were viruses and bacteria, and that even “sophisticated entities” like humans perhaps existed as an environment for their occupation.
The realization that viruses and bacteria thrive in the most extreme conditions on earth : in deep ice; in deep rock below deep oceans and even outside the International Space Station, makes it more than likely that humans have inadvertently contaminated every body where we have sent probes, even though we have worked diligently to avoid contamination.
2013 was also the year NASA’s chief Astrobiologist Chris McKay started talking about Panspermia and how asteroid and meteor collisions likely carried microbes from planet to planet in the early days of the formation of the planets. It is now mainstream science that of the 60,000 meteorites found on earth, 124 have been confirmed to come from Mars.
Universe Today, Dec 3, 2014 : According to a recent paper submitted by an international team of scientists, that evidence may have arrived on Earth three and a half years ago aboard a meteorite that fell in the Moroccan desert. Believed to have broken away from Mars 700,000 years ago, so-called Tissint meteorite has internal features that researchers say appear to be organic materials. The paper appeared in the scientific journal Meteoritics and Planetary Sciences. In it, the research team – which includes scientists from the Swiss Federal Institute of Technology in Lausanne (EPFL) – indicate organic carbon is located inside fissures in the rock. All indications are the meteorite is Martian in origin. “So far, there is no other theory that we find more compelling,” says Philippe Gillet, director of EPFL’s Earth and Planetary Sciences Laboratory. He and his colleagues from China, Japan and Germany performed a detailed analysis of organic carbon traces from a Martian meteorite, and have concluded that they have a very probable biological origin’.
As one of the original Rosetta Mission Principal Investigators, Professor Chandra Wickramasinghe has a long history of studying the interstellar medium. He and Sir Fred Hoyle, who would have been 100 next year (2015), developed the Hoyle-Wickramasinghe Model of the Panspermia. This was first proposed over 3 decades ago (Hoyle and Wickramasinghe, 1981). According to this theory comets carry not only organic molecules that could serve as chemical building blocks of life, but life itself in the form of freeze-dried microorganisms – bacteria and viruses.
There are two types of comets : the long period comets with orbits of 100,000 years originating in the Oort Cloud at the very edge of the Solar System; then the short period comets like 67P and Halley . The orbit of 67P is just 7 years. Wickramasinghe studied 67P last time around the sun 7 years ago, in 2007. One of the biggest questions concerning these short period comets is about what is causing the “geysers” to shoot out water and particles creating the well known cometary tails. It is much easier to understand the long period “Sungrazer Comets” like ISON which pass very close to the Sun and are often “sublimated” by the heat. But when the closest a comet gets to the Sun is between Earth and Mars, then there is no extreme heat? So just what is causing the pressure that forces the “geysers”, already seen coming out from 67P.
Two Papers are offered by Professor Wickramasinghe which Provide Background Reading for Rosetta Scientists Wickramasinghe has made available two papers to help the next generation of scientists understand the history of Cometary Panspermia theory and to encourage debate on these hypotheses as experimental evidence starts to be published by the Rosetta Team :
1. with Max Wallis : Outgassing due to ice-sublimation was already evident in September 2014 at 3.3AU, with surface temperature peaks of 220-230K, which implies impure ice mixtures with less strongly-bound H2O. Increasing rates of sublimation as Rosetta follows comet 67P around its 1.3 AU perihelion will further reveal the nature and prevalence of near-surface ices.
2. with Milton Wainwright : The evidence of refrozen seas and lakes plus the early outgassing activity point to the action of microbiology, which could also explain more distant outbursts. While microorganisms probably require liquid water bodies for their early colonising of a comet, they can inhabit cracks in ice and sub-crustal snow, especially if they contain anti-freeze salts and biopolymers. Some organisms metabolise at temperatures as low as 230K, explaining the coma out at 3.9AU and our prediction is that they would become increasingly active in the near-surface layers as the comet approaches its 1.3 AU perihelion. The detection of organic molecules at the surface by Philae and through IR imaging
These three scientists seek not to publish early to stake any claims. Rather they seek only to encourage and guide their younger peers – the Rosetta and NASA scientists- as they embrace the NASA challenge of “Starting the Difficult Challenge of Seeking the Signs of Life”.