An image taken by the Curiosity rover shows a wind-blown deposit dubbed "Rocknest" on Mars.

An image taken by the Curiosity rover shows a wind-blown deposit dubbed "Rocknest" on Mars. Photo: AFP/NASA

As Curiosity prepares for Thanksgiving on Mars, rover fans have been left hanging about a discovery from the Red Planet that a NASA official has billed as a big one.

Just you wait, NASA says.

This data is ... looking really good. 

John Grotzinger, rover mission

Not everyone wants to. Curiosity's Facebook page had one early-morning comment from a fan: "WHAT IS IT?!?!" Mars watchers were expressing the same sentiments on Twitter.

Curiosity's camera ... aka, the Mars Hand Lens Imager.

Curiosity's camera ... aka, the Mars Hand Lens Imager. Photo: Reuters/NASA

NPR stirred things up Tuesday with a report in which John Grotzinger, principal investigator for the rover mission, called the news a discovery for the history books: "This data is ... looking really good," he said.  The scientist said it would be several weeks before NASA had anything to say. Researchers are being very careful to make sure they get it right before they blab.

Early-morning attempts to reach contacts failed to unearth anyone willing to squeal.  Media reports are full of speculation. Did Curiosity "sniff signs of life?" asks Popsci.com.

But it looks like we'll just have to wait. We do know that the discovery was made by SAM, the Sample Analysis at Mars suite of three instruments, which analyses both soil and gases.

Curiosity digs up five scoopfuls of material from a patch of dusty sand called "Rocknest" on Mars.

Curiosity digs up five scoopfuls of material from a patch of dusty sand called "Rocknest" on Mars. Photo: AFP/NASA

"Think of it like a Swiss Army knife," SAM co-investigator Laurie Leshin said. "It's a beautifully integrated set of tools that can do many jobs ... and of course it's right there in Curiosity's pocket."

Scientists have been hoping to detect methane, which would indicate that there were once living things on Mars. And at one point it appeared that SAM had in fact found methane, according to NPR. But an announcement of that news was held up and, in the end, never came out because a second measurement showed no methane. That experience helps explain NASA's caution in discussing the latest finding.

Meanwhile, Curiosity continues to roll on Mars, although it will take a holiday break.  According to NASA, the rover had another first on Sunday, when it completed a touch-and-go inspection of one rock.

"We have done touches before, and we've done goes before, but this is our first 'touch-and-go' on the same day," Curiosity mission manager Michael Watkins said.

Over Thanksgiving, Curiosity's Mast Camera will be used to scout possible routes and targets, the space agency said.  Next up: choose a rock for the first use of the rover's hammering drill, to collect samples of rock powder.

Los Angeles Times