An unusual presentation by a recently-retired NASA scientist Dr. John Charles shares an unusual and highly entertaining presentation entitled “From here to Mars: How the Twins Study and the year-long ISS mission have moved us closer to the red planet”
The agenda of AGBT runs a wide range of topics, from the highly specific on the technology forefront (the MGISEQ-T7 technical details for example, that were made public for the first time at this venue) to the genome biology side (the spatial transcriptomics of melanoma during immunotherapy). And every so often there’s a guest speaker that captivates this highly technical scientific audience.
Some of the risks of spaceflight
Dr. John Charles has dedicated his career to studying the effects of spaceflight on the human body, with a doctorate in physiology and biophysics and joining NASA’s cardiovascular laboratory afterwards in 1983. Becoming the laboratory director in 1985, he has since worked on a number of spaceflight physiology issues, from orthostatic intolerance (the feeling of faintness upon return to Earth from orbit) to serving as project scientist for Space Shuttle Mission STS-95, working with John Glenn on his historic return to space.
Dr. Charles began by sharing a long list of hazards – some fourteen of them – including “spaceflight-induced intracranial hypertension” and somewhat well-known “bone fracture due to spaceflight-induced changes to bone”. I hadn’t considered things like “Renal stone formation” or “Adverse health effects of due to host microorganism interactions”. Spaceflight’s effect on human health is a complicated business.
And these risks are quantified. As the figure (and history) demonstrates, these risks are real.
He showed some of the remediation developed for radiation risk (kinds of protective wear) as well as the practical planning steps through careful scheduling of spaceflight. Another kind of risk is psychological – a ‘hostile closed environment’ and listed 12 different risks, including the risk of getting sufficient nutrition, as well as isolation. Being cooped up in a spacecraft with two others for two and a half years is something humans have not faced before, with ‘cognitive, behavioral, and psychiatric disorders’ all additional risks.
Being from NASA, he mentioned ‘behavioral and health decrements: inadequate cooperation, coordination and communication’, and there would need to have ‘countermeasures’ in order to ‘regain function’. I’ll have to use that phrase in the future when I am in a grumpy mood: “I sense I have a behavioral decrement; countermeasures taken immediately to improve function.”
Dr. Charles has been working with Dr. Chris Mason (Weill-Cornell Medical College) for five years on the biology of Mars spaceflight, and at AGBT 2017 he gave a memorable talk titled “DNA sequencing, genome assembly, and epigenetics on the international space station”. (I think it may have been the most memorable in terms of sheer amount of information and number of slides.)
The sheer complexity of space travel
Dr. Charles pointed out one perhaps obvious point to get into orbit: the entire spacecraft of many, many tons takes only 10 minutes to go from a stationary state to a speed of five miles per second, with an incredible amount of kinetic energy. And then upon re-entry (back to Earth), all that kinetic energy has to be dissipated for the vehicle to come to a stop.
It is difficult to comprehend interplanetary distances, as the longest distances we may travel could be inter-continental air travel of some 6,000 miles, not 6 million or 60 million miles. He stated some statistics about the distances – in this photo of Earth from the Mars rover Curiosity, the distance is 112 million miles away.
With a 30-day launch window of every 18 months (when the planets are close together), it will take 6 months to get to Mars, and another 6 months to return. (I presume the stay will be 6 months in duration). One interesting note he made: the current thinking is to use the moon (either on the moon or near it in orbit) as a staging area for fuel.
He then showed this interesting chart of time it takes for the human body to get into a steady-state; a time-course of physiological changes. He has devoted his career to developing ‘countermeasures’ for these physiological effects, and introduced the twin study.
He showed a chart outlining the history of the Russians’ long-term space duration, with several 1-year missions in the 1980’s. Valeri Polyakov had a record 14 months on the space station Mir in 1994.
The twins Mark and Scott Kelly both became astronauts, and they suggested the potential of using their identical genomes (or nearly-identical if you count the epigenome) as a natural experiment of the effect of long-term spaceflight. As astronauts are ‘equally assignable’, they have little choice themselves, and as Dr. Charles put it, ‘an N of 1 study is not ideal’. Originally Dr. Charles was against this idea. However he pointed to Mike Snyder’s Personal omics profiling work (Cell 2012) and in a classic NASA government maneuver, he was put in charge of a project he initially opposed.
The landmark Science paper has been accepted and is being prepared for publication. Dr. Chris Mason previewed some of the preliminary findings at the recent AAAS/Science conference in Washington DC, and the Economist recently published a podcast with an interview with Chris.
Dr. Charles showed this slide of the kinds of studies that are lined up right behind the landmark Science paper that will be published in a few weeks.
It was satisfying to see Dr. Graham Scott in the acknowledgements. For those who do not know Graham, he was a major force in the early 2000’s at Life Technologies marketing group to champion both the SOLiD and Ion Torrent NGS platforms worldwide, and joined NASA to help fund projects like this one about six years ago.