Sometimes I like to chill out after writing or teaching by listening to music on YouTube. I close the door and turn up the volume. One of my favorite dance tunes is "Mambo #5" by Lou Bega. Never fails to make me smile. I felt some of that same elation when NASA reported this week that the Mars Perseverance rover succeeded in obtaining its first core sample from the rock nicknamed Rochette. A previous attempt on a different rock came up empty when the sample apparently crumbled into powder before making it into the tube.
The rover used the drill at the end of its robotic arm to core out two samples from the suitcase-sized Rochette on Sept. 1 and again on the 7th. But the agency had to wait for better lighting to get a clear photo of the samples before announcing it had the goods. They're now safely inside hermetically sealed titanium tubes each about the thickness of a pencil.
This and up to 36 other samples from various locations along the rover's traverse will eventually be cached in multiple safe places on the surface. NASA and the European Space Agency are working together to plan a mission to land in Jezero Crater, pick up the tubes and return them to Earth for detailed analysis in late 2030 or 2031. Although 312 Martian meteorites have been found on Earth to date, these samples would be the first set of scientifically identified and selected materials returned to our planet from another.
Rochette appears to be a type of volcanic rock called basalt that possibly originated from an ancient lava flow. It rests atop "Artuby," a ridgeline more than a half-mile (900 meters) long near the crater's deepest and most ancient layers of exposed bedrock.
"It looks like our first rocks reveal a potentially habitable sustained environment,” said Ken Farley of Caltech, project scientist for the mission, which is led by NASA’s Jet Propulsion Laboratory in Southern California. “It’s a big deal that the water was there a long time.”
A preliminary analysis of the first two rock cores reveals the presence of salt which may have formed when groundwater — possibly from a long-ago lake that once filled the crater — seeped into the material. The salts also may have trapped tiny bubbles of ancient Martian water and even remnants of primitive life similar to what salts do on Earth. They're also good preserving food though it's unlikely we'll find a Martian's discarded cheese sandwich anytime soon.
We already know that water covered Jezero Crater in the distant past, which is one of the reasons it was selected as the mission's landing site. We just don't know for sure how long. Did a sudden flood fill the crater and then dry up? Or did water linger for millennia or even millions of years? Based on a first-look, the samples appear heavily altered by water, which would point to a lot of time spent "in the pool."
The question is a crucial one because the longer water is around the better chance life can develop and take hold. A key objective for Perseverance’s mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will also characterize the planet's geology and past climate. Everything we learn remotely will help inform a human mission to the Red Planet which could happen during the 2030s, although Elon Musk and company believe they can get a crew there by 2026.
Since its arrival on February 18th this year, Perseverance's has traveled about 2.2 kilometers. Its next sample site will likely be just 656 feet (200 meters) away in “South Séítah,” a series of ridges covered by sand dunes, boulders, and rock shards that resemble broken dinner plates. This site offers up older rocks that will help extend the planet's geological timeline.
Sample-coring will have to wait until later in October however because Mars will soon pass almost directly behind the sun from Earth's perspective. In other words, it will be in conjunction with the sun, which happens Oct. 8. During this time, solar activity from flares and other sources could potentially disrupt commands NASA might sent to the rover. To prevent corrupted information from causing a problem the agency will suspend communications Oct. 2-14.
In the months ahead, the rover will resume its science mission and fill as many as eight sampling tubes before returning to the original landing site. From there it will turn northwest and begin a second science campaign focused on the crater's fan-shaped delta. Here, long ago, a river cut a channel through Jezero's wall and emptied into "Lake Jezero." The region may harbor clays that can preserve fossilized signs of microbial life. More excitement and discovery lie ahead.
"Astro" Bob King is a freelance writer for the Duluth News Tribune. Read more of his work at duluthnewstribune.com/astrobob.