On the site Space.com, I found a nice article by David Powell about the Cassini spacecraft’s future. (Cassini has done some wonderful work recently, including bringing us wonderful images such as the one below of Titan and Epimetheus, and Saturn’s rings.)
Cassini’s NASA handlers are wondering about what they will do with it when its mission is over. Here are some of the options they are considering:
- Crash it into Saturn? Or perhaps a moon of Saturn? See what might be learned from the impact? Seems a bit dramatic, and there is a risk of contamination (of the moon especially) from any terrestrial contamination on the craft. -We don’t want to be accidentally seeding planets and other bodies with our life. Also, it is harder to crash into Saturn than you might think. It has a force sheild – its rings would make the planning full of unknowns.
- Hurl it out of the solar system (to later show up in an episode of some science fiction show)? Possibly. You’d have to plan a long series slingshot maneouvers around Titan to get that to work. This has the advantage of giving it a chance to pass by some Kuiper belt objects and maybe give us some pictures.
- Put it into a boring orbit where it is unlikely to encounter anything?
- Bring it back this way? Perhaps crash into Jupiter? Mercury?
Lots of options…. They’ll be chewing them over for a while. The full article is here.
-cvj
Brown:
The key word is “accidentally.”
While many people may be in favor of seeding other planets, I think they’d like to actually know if it will work, and what they’re using.
Simply crashing a spacecraft that may or may not have any microbes, with no way to measure whether it worked or not doesn’t really help anybody.
I vote for sending Cassini out of the system to pursue the Pioneer anomaly. Although the Wikipedia entry that Clifford linked to indicates a reason to doubt Cassini data on that score, I’m still fond of the idea.
At first I thought the title referred to physicists.Would have been more interesting.
If you Google on “Planetary Protection”, you can see some of the issues. For bodies that are ‘protected’, each are assigned a protection category which must be considered in the decision process for ending a mission. Enceladus and Titan are at or near the highest category of protection for Cassini mission designers, so those two objects will be avoided to the nth degree.
Why would we crash it into a planet at all if not for the scientific knowledge gained?
Not obvious to me at all.
You act as if a pristine experimental environment should be mankinds primary interest. That our search for scientific knowledge should trump all else.
I would bet that a signifigant fraction of the “deciders” would disagree.
I don’t know. It would be awfully nice if we could. For interested parties, see here.
-cvj
Ooooh! Can we test the Pioneer anomaly, or does Cassini’s acceleration-determining equipment not roll like that?
Why would you want to contaminate that which you wish to study?
Let’s say we contaminate mars (or some more fluidly active body, like a suitable moon of Saturn) with bacteria form earth….. then later on we go there on a mission to look for bacteria, in order to understand cases of life elsewhere… to better understand our own life on earth. Would this not be awfuly confusing? Same goes for anything we touch that we don’t understand…. we want our touch to be as light (or as clearly distinguishable) as possible.
-cvj
You seem pretty sure of this statement?? Almost like it’s blatently obvious to everyone…..It’s not at all obvious to me.
Charmashanti- Not anytime soon. The extended mission (another 4 years) seems guaranteed. Beyond that (2012?), I guess is up in the air.
The reason that Cassini spacecraft planning needs so many years in advance is because there is no spinning portion of the spacecraft holding all instruments, like what existed with previous space missions such as Galileo. Such a spacecraft with a spinning portion gave all of the instruments equal access to the object at nadir. For example, the dust instrument and the camera on Cassini are mounted at opposite sides of the spacecraft, but if only one can observe the object and both teams have an interest in taking measurements of the same object, then how are observations managed? Carefully and with much time, since every measurement must be negotiated between the instrument teams.
I would guess that the other factors making future long-term planning difficult is the sheer number of instruments and their different maintenance requirements and perhaps different lifetimes.
It’s sad to see such an extraordinary project as Cassini meet its demise. Such amazing photos.