Dateline: November 5 2045 Interview between Ivan Felson and Prof Henry Parson.
IF: So, Professor Parson - Have we discovered Alien intelligent life? Should we be afraid or excited? and Can we communicate with them?
HP:To answer these questions - Yes, we believe we have. At this stage we should be excited, not afraid, but we should probably tread carefully, and not yet. We have a few ideas about how we should proceed with communication, but admittedly, we are a bit stumped.
IF: So, before we get ahead of ourselves, how did it all happen, and what have we done in the past that we may regret with our new knowledge.
HP: Well, it all started to dawn on us from the Rosetta probe onwards. Rosetta discovered not just a liquid water core, but four liquid interior water lakes seperated by solid structures. The surface analysis of the chemistry revealed a rich organic chemistry akin to crude oil, with PAH's, long chain hydrocarbons, with optical properties (chirality) just as crude oil from biotic origin rather than racemic as you would expect from synthetic or non-biotic origin sources.
The surface that the Philae lander was on, was therefore spongy rather than solid. Even though gravity was negligible, it seemed obvious that it would probably eventually sink. Experiments were accelerated and adjusted with the given constraints, and as the comet started to form a coma, the surface started to subside downwards and eventually Philae got subsumed into the comet and could not operate any further.
The orbiting Rosetta craft continued to observe the comet, and its mission was extended and continued to operate for another decade and the whole cometary orbit cycle was observed up close.
At that point, the main regret was not to have specific life detection equipment on board - The spacecraft were not even sterilised as would be normal where possible alien life were to be detected.
With these discoveries, a plethora of new comet missions were financed from all spacefaring nations.
Comets that had already been visited were visited again with orbiters. "peanut shaped" comets Borrely and Hartley 2 were found to have liquid water within both "nuts" and the two ends were noticably further apart, and the neck separating them were thinner. There were various surface structures like jets (round holes in the surface) that had no gas or dust coming out. Finally, a probe was sent into one of those holes and a sample returned with complex DNA similar to a megavirus, as well as biotic material of various kinds.
The shape of the jets below the surface was a network of tunnels something like a huge set of lungs. The shape of the non jet holes were vertical towards the centre of one of the liquid lakes or other. Surface features were sculpted from below - hills welling up from heated hydrocarbon pumping up, and valleys were where warming volatiles were directed towards the "lungs", causing the surface to subsume. The temperature in the interior of the comet remained quite stable, and the liquid lakes stayed a constant volume and overall shape over the period of the comet.
Deep Impact mission appeared to be more of a mistake at this point. We basically shot a copper bullet into what now appears to be a living organism. It is no wonder the comet changed rotation and thus future orbit quite substantially.
2014 was a watershed year for comets - Not only Rosetta, but also the flyby of Comet Siding Spring past Mars also. Comet was also pitch black - Why is that interesting? It was supposedly the first time in from the Oort Cloud. Comets were supposed to be pristine and icy - Time and time again they have proven to be black - the opposite of pristine.
Rosetta took some of the interest away from Dawn's also amazing discoveries at Ceres in 2015. Subsurface liquid water doesn't seem to be such a big deal if it exists on every comet, as well as other places such as Ceres and Jupiter's icy moons. It is just easier to get on, off, and around a comet or dormant comets