Nasa Mars announcement: Red Planet could have building blocks of life, Curiosity rover shows – as it happened

There's still about 90 minutes before we find out what Nasa has found on Mars. But in the meantime they've sent an additional alert about a spacewalk due to take place next week:

NASA astronauts will embark on a six-and-a-half-hour spacewalk Thursday, June 14, during which they will install new high-definition cameras to capture spacecraft docking with the International Space Station, including new American-made spacecraft with scheduled test flights later this year.

Live coverage of the planned spacewalk by American astronauts Drew Feustel and Ricky Arnold will begin at 6:30 a.m. EDT on NASA Television and the agency’s website.

Feustel, commander of the station’s Expedition 56, and flight engineer Arnold are scheduled to begin the spacewalk at 8:10 a.m.

The two spacewalkers will install brackets and high-definition cameras near an international docking adapter mated to the front end of the station’s Harmony module. The additions will provide enhanced views during the final phase of approach and docking of the SpaceX Crew Dragon and Boeing Starliner commercial crew spacecraft that will soon begin launching from American soil.

During their spacewalk, the astronauts also will swap out a camera assembly on the starboard truss of the station and close an aperture door on an external environmental imaging experiment outside the Japanese Kibo module. The imaging experiment hardware will be discarded on a future SpaceX cargo resupply mission.

The spacewalk will be the 211th in support of space station assembly and maintenance and the sixth station spacewalk this year. It also will be the ninth spacewalk in Feustel’s career and the fifth for Arnold. During the spacewalk, Arnold will wear a suit bearing red stripes while Feustel’s suit will have no stripes.

At five hours and 23 minutes into the spacewalk, Feustel will surpass NASA astronaut Peggy Whitson’s record of 60 hours and 21 minutes to move into third place for cumulative time spent during spacewalks.

Just a couple of minutes until Nasa's presentation kicks off and the world finds what it has found on that other world.

Nasa has found intriguing organic molecules on Mars, it has said. Here's the full details.

Nasa wants to make clear that it hasn't found life. But those organic molecules can be understood as the building blocks of life and are strongly associated with it here on Earth – meaning that the new discovery could be a significant way of understanding not only whether Mars once had life but whether it could still continue to support it.

Here's Reuters' report on the new findings:

A NASA rover has detected a bonanza of organic compounds on the surface of Mars and seasonal fluctuations of atmospheric methane in findings released on Thursday that mark some of the strongest evidence ever that Earth's neighbor may have harbored life.

But National Aeronautics and Space Administration scientists emphasized there could be nonbiological explanations for both discoveries made by the Curiosity rover at a site called Gale crater, leaving the issue of Martian life a tantalizing but unanswered question.

Three different types of organic molecules were discovered when the rover dug just 2 inches (5 cm) into roughly 3.5 billion-year-old mudstone, a fine-grained sedimentary rock, at Gale crater, apparently the site of a large lake when ancient Mars was warmer and wetter than the desolate planet it is today.

Curiosity also measured an unexpectedly large seasonal cycle in the low levels of atmospheric methane. About 95 percent of the methane in Earth's atmosphere is produced from biological activity, though the scientists said it is too soon to know if the Martian methane also is related to life.

Organic molecules are the building blocks of life, though they can also be produced by chemical reactions unrelated to life. The scientists said it is premature to know whether or not the compounds were created in biological processes.

Whether anywhere other than Earth has harbored life, perhaps even in microbial form, is one of the paramount questions in science.

"There's three possible sources for the organic material," said astrobiologist Jennifer Eigenbrode of NASA's Goddard Space Flight Center in Maryland. "The first one would be life, which we don't know about. The second would be meteorites. And the last one is geological processes, meaning the rock-forming processes themselves."

The rover, which has allowed scientists to explore whether Mars ever boasted conditions conducive to life, in 2014 made the first definitive detection of organic molecules, also in Gale crater rock formed from ancient lake sediment - but it was a much more limited set of compounds.

"What the organic detections in the rock do is to add to the story of habitability. It tells us that this ancient environment on Mars could have supported life," Eigenbrode said. "Everything that was needed to support life was there. But it doesn't tell us that life was there."

Christopher Webster, an atmospheric science research fellow at NASA's Jet Propulsion Laboratory in California, said it is possible existing microbes are contributing to the Martian atmospheric methane.

"With this new data, we again cannot rule out microbial activity as a potential source," Webster said.

The amount of methane peaked at the end of summer in the northern hemisphere at about 2.7 times the level of the lowest seasonal amount.

The scientists were surprised to find organic compounds, especially in the amounts detected, considering the harsh conditions, including bombardment of solar radiation on the Martian surface. After drilling, Curiosity heats the rock samples, releasing the compounds.

Referring to the findings regarding organic compounds and methane, Webster said, "They hint at an earlier time on Mars when water was present and the existence of primitive life forms was possible."

The scientists hope to find better preserved organic compounds with Curiosity or other rovers that would allow them to check for chemical signatures of life.

The research was published in the journal Science.

And here's the Associated Press's report:

New Mars discoveries are advancing the case for possible life on the red planet, past or even present. 

Scientists reported Thursday that NASA's Curiosity rover has found potential building blocks of life in an ancient Martian lakebed. Hints have been found before, but this is the best evidence yet. 

The organic molecules preserved in 3.5 billion-year-old bedrock in Gale Crater — believed to once contain a shallow lake the size of Florida's Lake Okeechobee — suggest conditions back then may have been conducive to life. That leaves open the possibility that microorganisms once populated our planetary neighbor and still might. 

"The chances of being able to find signs of ancient life with future missions, if life ever was present, just went up," said Curiosity's project scientist, Ashwin Vasavada of NASA's Jet Propulsion Laboratory in Pasadena, California. 

Curiosity also has confirmed sharp seasonal increases of methane in the Martian atmosphere. Researchers said they can't rule out a biological source. Most of Earth's atmospheric methane comes from animal and plant life, and the environment itself. 

The two studies appear in the journal Science . In a companion article, an outside expert describes the findings as "breakthroughs in astrobiology." 

"The question of whether life might have originated or existed on Mars is a lot more opportune now that we know that organic molecules were present on its surface at the time," wrote Utrecht University astrobiologist Inge Loes ten Kate of the Netherlands. 

Kirsten Siebach, a Rice University geologist who also was not involved in the studies, is equally excited. She said the discoveries break down some of the strongest arguments put forward by life-on-Mars skeptics, herself included. 

"The big takeaway is that we can find evidence. We can find organic matter preserved in mudstones that are more than 3 billion years old," Siebach said. "And we see releases of gas today that could be related to life in the subsurface or at the very least are probably related to warm water or environments where Earth life would be happy living." 

The methane observations provide "one of the most compelling" cases for present-day life, she said. 

Scientists agree more powerful spacecraft — and, ideally, rocks returned to Earth from Mars — are needed to prove whether tiny organisms like bacteria ever existed on the red planet. 

JPL's Christopher Webster, lead author on the study, said it's the first time Martian methane has shown a repeated pattern. The magnitude of these seasonal peaks — by a factor of three — was far more than scientists expected. "We were just blown away," he said. "It's tripling ... that's a huge, huge difference." 

Webster theorizes the methane created either now or long ago is seeping from deep underground reservoirs up through cracks and fissures in the crust. Once at the surface, the methane sticks to dirt and rocks, with more released into the atmosphere when it's hotter. 

"We have no proof that the methane is formed biologically, but we cannot rule it out, even with this new data set," Webster said. 

Scientists have been seeking organic molecules on Mars ever since the 1976 Viking landers. The twin Vikings came up pretty much empty. 

Arriving at Mars in 2012 with a drill and its own onboard labs, Curiosity confirmed the presence of organics in rocks in 2013, but the molecules weren't exactly what scientists expected. So they looked elsewhere. The key samples in the latest findings came from a spot 4 miles (6.4 kilometers) away. 

As with methane, there could well be non-biological explanations for the presence of carbon-containing molecules on Mars, such as geologic processes or impacts by asteroids, comet, meteors and interplanetary dust. 

Jennifer Eigenbrode, an astrobiologist at NASA's Goddard Space Flight Center in Greenbelt, Maryland who led the organics study, said she's intrigued by the possibility that life might have existed and adapted on Mars. 

"I'm equally as fascinated by the idea that life never got started on Mars in the first place. That's a harder question to address scientifically, but I think that we need to give the search for life on Mars due diligence. We need to go to places that we think are the most likely places to find it."

The overwhelming message from Nasa is this: it's not life, yet, but we're getting a lot closer to thinking there might be and proving that.

“With these new findings, Mars is telling us to stay the course and keep searching for evidence of life,” said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters, in Washington. “I’m confident that our ongoing and planned missions will unlock even more breathtaking discoveries on the Red Planet.”