Two astronomical updates for you today; one good, one bad.
Let’s start with the bad news. Two faulty helium valves on the Juno spacecraft mean that it is unlikely that it will be able to make the super close orbits that had been intended. The plan was that Juno’s elliptical orbit would be ever curtailed eventually bringing the craft to within just a couple of thousand kilometres of the planet’s surface.
On the one hand this would be extremely dangerous for the craft as this would bring it into a highly radioactive region which could have detrimentally affected onboard systems despite its heavy shielding. It would, though, have provided an unprecedented opportunity for studying the magnetic activity of Jupiter whilst also revealing insights into the internal structure of the giant planet, something we know almost nothing about.
The plan now is to keep Juno in its present 53 day orbit. This means it won’t be able to get as close but, on the up side, it may well last longer as it won’t have to deal with the intense radiation. NASA feels that this gives the mission the best chance of achieving its science goals. Who knows? Maybe once they’ve done all they can from their current orbit they’ll give the dice a throw once there is less at stake. I’ll keep you posted.
The good news story is that NASA has taken another step forward in having a mission where the primary goal would be to look for life elsewhere in the solar system. This hasn’t been the case since the Viking landers of the 1970s.
The mission would be likely to head for Jupiter’s moon Europa, an icy world thought to have an underground ocean of liquid water, the one thing we’re sure of that all life we know about needs to survive. At this point it is all highly speculative, the mission would be unlikely to launch for twenty years or so. If you want to comb through what detail exists so far then here is the link to the >250 page report open for scientific consultation released by NASA last week. It’s thorough.
One of the key concerns in any mission looking for life elsewhere in the solar system, or indeed to any world where there would be a reasonable chance of life existing, is that what we send has to be completely sterile. This is for two good reasons: first, we don’t want to contaminate the world with earth’s life; second, we don’t want to find a false positive.
Sterilisation is easier said than done, though. Other than not introducing any microorganisms in the first place during construction, the best ways to sterilise spacecraft is to irradiate them or to bake them. Highly sensitive onboard systems, however, may not take well to such rough treatment.
It’s imperative, though; it’d be a terrible shame to spend billions of dollars, travel hundreds of millions of kilometres over several years only to discover E. coli from the salad in the Jet Propulsion Lab staff canteen.