Tagged: NASA

NASA’s Mars Curiosity rover has been on the Red Planet for 2,000 days

With the increasingly steady stream of Mars-related news over the past couple of years it can be easy to forget that NASA has had high-tech hardware rolling around on the planet’s surface for quite a while now. We got a great reminder of that today, as NASA’s Mars Curiosity rover is celebrating its 2,000th Martian day rolling around on the dusty world. The journey hasn’t always been easy, and NASA has be forced to rethink its approach to solving problems on more than one occasion, but Curiosity has far outlived its original mission timeline.

NASA measures Curiosity’s time on the planet in Martian days, called sols, which are slightly longer than Earth days. Its 2,000 sols equals 2,054 Earth days, which is even more impressive.

Curiosity was originally launched in late November of 2011. It arrived on Mars on August 6th, 2012, and NASA planned for the rover to last just shy of 700 Earth days, or 668 Martian sols. It has nearly tripled that original goal, and traveled far more than NASA could have possibly hoped for.

Curiosity’s lengthy stay on Mars has come with its fair share of issues. Most recently, the rover’s drill extension mechanism failed, forcing NASA to invent a new way of using the implement without relying on the faulty hardware. It was a trying time for the Curiosity team, but that’s just part of the job when working with now-antiquated hardware that’s been exploring another planet for over five years.

To celebrate Curiosity’s achievement, NASA released a stunning new image captured by the rover earlier this year. The photo is a shot of Mount Sharp which the rover has been exploring for the past three years. It’s a composite image pieced together from several photographs, and it’s a timely reminder of the harsh conditions Curiosity has been forced to endure during its 2,000 days of exploration.

Actually, Astronaut Scott Kelly’s DNA was not altered in space

NASA astronaut Scott Kelly spent nearly a year in space so the agency could study the long-term effects on the human body, in preparation for longer missions that could one day take us to Mars and beyond. Upon his return, he discovered his overall health was not to be what it used to be — and NASA had a Kelly replica at home to compare Scott against. That’s his twin brother, Mark, an astronaut who stayed on Earth while his brother was circling our planet.

The early conclusions of a recent NASA study implied that Scott’s DNA has been altered by 7%, which seemed to be a startling discovery of what space can do to the human body. However, that’s a wrong interpretation of NASA’s announcements. It turns out that while Scott’s DNA was affected by exposure to space, his DNA is still nearly identical to his brother’s, as it should be.

What NASA really discovered is that, while DNA mutations were observed after Scott’s return from space, it was his gene expression that changed by 7%, compared to his brother. However, the agency’s choice of words may have made it sound like Scott’s DNA was permanently altered. The agency updated that press release to make it clear that Scott and Mark are still identical twins.

The DNA code that serves as the programming language for any living body, including humans, has not changed for Scott. Gene expression did change by 7%, though. But that only means Scott’s body adapted the way it functions after his exposure to space, even though it’s been taking information from the same DNA code.

Scott’s 7% gene expression differences concern the immune system, DNA repair, bone formation, and more, according to the NASA. The phenomenon happens on Earth as well, and it’s a response to a person’s environment.

“To have 7 percent of his gene expression changed after the spaceflight does not mean that 7 percent of the DNA changed, or that those changes were necessarily due to mutations,” UC Davis geneticist Nichole Holm told The Verge — she did not work on the Twins Study.

“The two are still very much identical twins,” Holm said. “They possessed different mutations before and after the flight, and Scott experienced different changes in his RNA, not DNA. But their DNA is still nearly identical and much more similar to each other than to any other person on earth (or in space).”

NASA also confirmed that Scott’s DNA did not change.

Scott’s DNA did not fundamentally change,” a NASA spokesperson said. “What researchers did observe are changes in gene expression, which is how your body reacts to your environment. This likely is within the range for humans under stress, such as mountain climbing or SCUBA diving.”

The spokesperson continued, “We are at the beginning of our understanding of how space flight affects the molecular level of the human body. NASA and the other researchers collaborating on these studies expect to announce more comprehensive results on the Twins Studies this summer.”

NASA will announce more details soon, hopefully in clearer wording that will avoid confusion.

NASA captures gorgeous photo of Saturn’s ice-covered moon Dione

NASA has spent a significant amount of time studying Saturn’s moons Titan and Enceladus, and while those are the two we most often hear about and see photos of, the planet has many more natural satellites that deserve our attention. It might be hard to believe, since Earth only has a single moon in its night sky, but Saturn has at least 62 moons. Many of them are quite small, but Dione is one of the larger ones. Showcasing a photo of Dione taken by the now-destroyed Cassini spacecraft, NASA explains what little we know about the frosty world.

The photo was originally taken way back in July of 2012, but it’s still a rather stunning glimpse at the far-off moon. According to NASA, the photo was taken when Cassini was at a distance of about 260,000 miles from its surface, which is close enough to reveal some of the most interesting details of its surface.

“Dione is about 698 miles (1,123 kilometers) across,” NASA explains. “Its density suggests that about a third of the moon is made up of a dense core (probably silicate rock) with the remainder of its material being water ice. At Dione’s average temperature of -304 degrees Fahrenheit (-186 degrees Celsius), ice is so hard it behaves like rock.”

The ice-covered moon is Saturn’s fourth largest in terms of overall size, and like its smaller brother Enceladus, it’s thought that its orbit around Saturn is capable of tidal heating. That means that liquid water may be present deep under its frozen crust, which is tantalizing for alien hunters and astronomers alike.

“A picture is emerging that suggests Dione could be a fossil of the wondrous activity Cassini discovered spraying from Saturn’s geyser moon Enceladus or perhaps a weaker copycat Enceladus,” Bonnie Buratti of NASA’s Jet Propulsion Laboratory says. “There may turn out to be many more active worlds with water out there than we previously thought.”

Observations of Dione by Cassini have revealed the presence of massive cracks in its icy surface, similar to those present on Enceladus. It is thought that its hard crust may still be faintly spraying water, though not to the same degree of its smaller brother.

NASA astronaut who spent a year in space now has different DNA from his twin

Space travel is dangerous for a lot of very obvious reasons — traveling off of Earth on a rocket has its risks, after all — but even when everything goes well it seems that a brief stay in space has the potential to alter a person’s very DNA. That’s the takeaway from a long-term NASA study that used astronaut Scott Kelly and his twin brother Mark as guinea pigs to see how living in space can affect the most basic building blocks of life.

Scott Kelly has spent over 500 days in space overall, but a huge chunk of that came with a single mission which had him stay aboard the International Space Station for 342 days. His brother Mark, who is a retired astronaut, is his identical twin and has the same DNA. This provided a never-before-possible opportunity for NASA to study how long-term space travel affects the human body and the genes that make us who we are. As it turns out, space really does change us, and upon Scott’s return to Earth it was discovered that his DNA has significantly changed.

“Scott’s telomeres (endcaps of chromosomes that shorten as one ages) actually became significantly longer in space,” NASA explains. “While this finding was presented in 2017, the team verified this unexpected change with multiple assays and genomics testing. Additionally, a new finding is that the majority of those telomeres shortened within two days of Scott’s return to Earth.”

Most of Scott’s genes did indeed return to normal after a brief time back here on Earth, but not all of them. According to researchers, around 7% of Scott Kelly’s genes have shown long-lasting changes when compared to his brother’s. Those changes have remained for the two years since he returned to solid ground, which surprised even him.

“I did read in the newspaper the other day that 7 percent of my DNA had changed permanently,” Kelly said in a recent interview. “And I’m reading that, I’m like, ‘Huh, well that’s weird.’”

The “Twins Study” was a preliminary step in the lead-up to an eventual long-haul manned mission to Mars. NASA has some vague plans in place for such a mission and is currently working on the technology to actually make that happen, but the human element cannot be overlooked. A Mars mission would last as long as three years, which would obviously be the longest stretch that any human has been away from Earth. Can the human body handle such a journey? We might not have to wait very long to find out, as some are expecting the first manned Mars trip to happen as soon as the 2030s.