Mars InSight two days away from its Seven Minutes of Terror
Saturday, November 24, 2018, 10:38 PM - Just two days from now, NASA's InSight lander will plunge into the Martian atmosphere for a seven-minute, white-knuckle thrill ride to the surface of the Red Planet. Plus, a new idea for putting a spacecraft into orbit around Pluto, and the final days of NASA's exoplanet hunter. It's What's Up In Space!
INSIGHT'S SEVEN MINUTES OF TERROR
A little over 6 years ago, NASA's Curiosity rover had its human team members on the edge of their seats, as it made an entirely automated, computer-controlled descent from the top of Mars' atmosphere to the surface.
According to Entry, Descent & Landing (EDL) engineer Tom Rivellini, at the time, Curiosity's landing was called 'Seven Minutes of Terror'. In his words, this was "because we've got literally seven minutes to get from the top of the atmosphere to the surface of Mars, going from 13 thousand miles per hour to zero, in perfect sequence, perfect choreography, perfect timing, and the computer has to do it all by itself, with no help from the ground. If any one thing doesn't work just right, it's game over."
Lead EDL engineer Adam Steltzner added to this, at the time, saying that due to the distance between Earth and Mars at the time, the communication lag was 14 minutes. So, with the seven minute descent to the surface, by the time NASA received the signal Curiosity had sent just as it reached the top of Mars' atmosphere, and thus had just started its descent, the rover had already been on the ground for seven minutes, either in one piece, ready to receive commands, or in a thousand pieces, scattered across the Martian landscape.
Now, another group of NASA EDL engineers are just weeks away from going through this anxiety-filled seven minutes.
Watch below as Rob Manning, chief engineer at NASA’s Jet Propulsion Laboratory, explains the critical steps of InSight's landing.
The InSight lander, NASA's mission to probe the interior of Mars for 'marsquakes', is set to reach the Red Planet on November 26. When it does, it will make the same 'seven minutes of terror' descent to the surface of Mars, slowing from 13,200 miles per hour (21,200 km/h) at the top of the atmosphere, to zero at the surface.
The only big differences between the Curiosity and InSight landings are 1) Insight will make a direct landing on Mars, using its own thrusters, rather than the 'sky crane' method that Curiosity used, and 2) Mars will only be eight light minutes away from Earth, so when NASA receives the signal that InSight has started its descent, it will have been on the surface, 'alive' or 'dead', for about a minute.
This illustrated sequence shows the stages of Mars Insight's descent. Credit: NASA JPL
Without the added complication of the sky crane, InSight's landing will be very much like the one performed by NASA's Phoenix mission, which landed back in May 2008. Still, according to NASA, Phoenix landed at a lower elevation than InSight will, and thus it had an extra kilometre and a half of atmosphere to fly through, to help with its braking, than InSight will have. Even with Mars' extremely thin atmosphere (compared to Earth), an 1.5 extra kilometres would really help.
Fortunately, InSight's parachute is much stronger than Phoenix's, with stronger support cables, so it will deploy earlier in the landing, giving it more time to slow InSight's descent.
Read more of The Weather Network's coverage of the InSight landing on the Out of this World blog.
GROUNDBREAKING IDEA FOR RETURN TO PLUTO
When NASA's New Horizon's spacecraft sped past Pluto and its moons, over three years ago, it gave us a frustratingly brief look at these remarkable worlds.
These near-true colour looks at Pluto and Charon were captured as New Horizons passed by these worlds in July of 2015. Credit: NASA/JHUAPL/SwRI
As amazing as it was to see Pluto, Charon and the smaller moons this close-up, we were left wanting more. Much more!
Now, a team at the Southwest Research Institute, led by Dr. Alan Stern - the same planetary scientist headed up the New Horizons mission - have come up with a new idea for a Pluto mission. Rather than just another flyby, however, this would be so much better - putting a spacecraft in orbit around the Pluto system, and using the gravity of Pluto's largest moon, Charon, to propel it around that region of space, to fully investigate the system.
According to SwRI:
The team first discovered how numerous key scientific objectives can be met using gravity assists from Pluto’s giant satellite, Charon, rather than propellant, allowing the orbiter to change its orbit repeatedly to investigate various aspects of Pluto, its atmosphere, its five moons, and its solar wind interactions for up to several years. The second achievement demonstrates that, upon completing its science objectives at Pluto, the orbiter can then use Charon’s gravity to escape the system without using fuel, slinging the spacecraft into the Kuiper Belt to use the same electric propulsion system it used to enter Pluto orbit to then explore other dwarf planets and smaller Kuiper Belt bodies.
CLICK TO ENLARGE. This complicated 'spaghetti' of lines represents this proposed spacecraft's use of Charon's gravity (rather than its own fuel) to fling it around the Pluto system, and out far enough to investigate other targets that may be nearby. Credit: Southwest Research Institute
"This is groundbreaking," Stern said in the SwRI press release. "Previously, NASA and the planetary science community thought the next step in Kuiper Belt exploration would be to choose between 'going deep' in the study of Pluto and its moons or 'going broad' by examining smaller Kuiper Belt objects and another dwarf planet for comparison to Pluto. The planetary science community debated which was the right next step. Our studies show you can do both in a single mission: it's a game changer."
THE KEPLER TELESCOPE'S LAST GASP?
NASA's Kepler Telescope has found thousands of planets orbiting around other stars, with thousands more waiting 'in the wings' for confirmation, and there's even more data that scientists and citizen scientists need to crawl through, to locate even more.
NASA's Kepler Space Telescope follows along behind Earth, in its orbit around the Sun, while searching for tell-tail 'transits' that indicate the presence of planets around other stars. Credit: NASA
This week, though, after months of squeezing every last bit of science potential out of this telescope, it seems that we've likely heard our very last from Kepler.
According to the latest Kepler update from NASA, dated October 23:
Following a successful return of data from the last observation campaign, the Kepler team commanded the spacecraft into position to begin collecting data for its next campaign. On Friday October 19, during a regularly scheduled spacecraft contact using NASA’s Deep Space Network, the team learned that the spacecraft had transitioned to its no-fuel-use sleep mode. The Kepler team is currently assessing the cause and evaluating possible next steps.
Given that the telescope has, essentially, been running on fumes as of late, the chances that this is simply the end of its mission are probably quite high.
With the launch of TESS - NASA's Transiting Exoplanet Survey Satellite - which may have already found its first exoplanet, this is certainly a fine time for Kepler to pass on the torch, after two very successful missions.