Our ability to directly explore the cosmos has been limited to a small number of lunar and interplanetary missions. NASA's Starlight program points to a way forward for sending small spacecraft to other stars using remotely directed energy propulsion. These miniaturized spacecraft will be capable of robotic exploration, but will also be able to carry small organisms. Researchers are obviously thinking of tardigrades.
Several government agencies and private companies aspire to establish themselves permanently on the Moon, then on Mars. Regarding interstellar missions, no plan is on the table. Although there are proposals for sending robotic missions, sending astronauts to a nearby system is simply not yet possible . On the other hand, interstellar missions could possibly be carried out in the near future with tardigrades. At least that's what new research to appear next January in the journal Acta Astronautica suggests.
For this work, the team focused on NASA's Starlight program, and how it could enable interstellar biological studies using radiation tolerant microorganisms .
Starlight is a program founded by NASA in 2009 to study how directed (laser) energy could be used to propel small spacecraft to relativistic speeds (close to that of light in a vacuum). Other similar projects emerged a few years ago, such as the Breakthrough Starshot, an ambitious interstellar mission to reach Alpha Centauri, the nearest star system, in just twenty years. The main attraction of dinghy sailing is the fact that it does not require propellant, which makes it particularly light and easy to accelerate.
Until now, however, all of these projects have not involved any form of life. The goal was simply to reach the nearest star and collect as much information as possible using onboard instruments.
However, as Stephen Lantin and his team at the University of Florida demonstrate, such a mission could also enable biological studies in deep space, such as testing the effects of radiation and extreme conditions of the interstellar medium on living beings .
As an example, the team considered tardigrades which are known for their incredible resilience in the face of extreme temperatures and pressures, radiation, dehydration, starvation and even near empty space.
Several tests have already been conducted in near space in which these small water bears were exposed to extreme cold and solar radiation. In all cases, these tardigrades survived conditions that would have killed other organisms . In fact, some have even succeeded in producing healthy offspring after exposure to the vacuum of space.
As such, tardigrades would therefore be ideal candidates to test this type of study which could have in fine far-reaching implications for future manned deep-space missions. Beyond these considerations, this type of project could also give more credibility (or not) to the very interesting hypothesis of panspermia.
Naturally, there are still a number of technical challenges to overcome before a mission of this type can be mounted and launched. However, there is progress.
