Emily LakdawallaMar 06, 2008

Rhea has rings!

At least that's what some members of the Cassini science team argue in a paper published today in Science magazine. I've just posted a news story explaining the discovery of possible rings at Rhea. This should inspire some space artists!

This is a story I've been waiting to see for a very long time. I first got wind of the story last June, when there was an item about Cassini using its camera to search for possible rings at Rhea in the weekly Cassini Significant Events Report for June 15, 2007. That piqued my curiosity and I whipped up a post about there being several items of interest in that report, culminating with the surprising story of possible rings around a moon!

Almost immediately I got an email from Geraint Jones, the lead author on the paper I summarize in the news story, who was, it turns out, horrified to see that the item had been mentioned in the Significant Events report, and he very politely requested that I remove the mention from my blog entry (which became much less interesting without it), as he was also requesting that JPL remove it from the online version of the report.

The problem wasn't that Cassini's activities were a huge secret; after all, most of the members of the enormous science team had already been apprised of this interesting result (I found out later) at their regular project science group meetings. The problem is that Jones was preparing the research for submission to either Nature or Science, and those two prestigious journals are particularly nitpicky about accepting research for publication that has already been discussed elsewhere. If word of this find got out, those two journals might turn him down.

I didn't have to accede to Jones' request, since I'd gotten the news from a public source, a document that had been emailed to the hundreds or thousands of people who subscribe to the Significant Event Reports. But, the news was taken down from JPL's website, and no one else seemed to have noticed it, at least not in any of the public forums or blogs that I read. And, like I said, he asked me very nicely. So I quietly took it down too; and no readers sent me any emails asking me about the quickly-removed story. So, Jones was safe until his research finally appeared in print in tomorrow's issue of Science -- at which point it was safe for him to talk to me too.

I get the idea that not everyone is convinced that these rings really exist, possibly because several attempts at imaging them have failed to make them visible. Hopefully Cassini will eventually be able to gather more data that will be able to lend more surety to Jones' conclusion.

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