MARS

[jamshundred]

Images from Spirit, Opportunity, and Curiosity rovers.

[genebo]

The NASA channel will carry the next Rover landing on Mars this afternoon, 2/18/2021

[jamshundred]

Rover descent and landing.  Great clarity

[jamshundred]

Gene,

this is GREAT video.  Not a single tree it seems.

[genebo]

The first thing that happened in this video was when the parachute deployed. This is an incredibly difficult maneuver, due to the thin atmosphere. A normal deployment as would be used on Earth would not properly inflate the canopy.

Viggo G. Dereng was a highly qualified machinist, working at NASA Langley back in the 1980's. He addressed this problem himself. He built a wind tunnel in his back yard to prove his theories. He developed a series of cords to only permit the canopy to inflate one little section at a time until that section was perfectly inflated, then cut the cords that held the next section in place and let it inflate perfectly. This process was repeated over and over until the entire canopy was inflated.

The process required some very tedious sewing of the cords to restrain the canopy until just the right time. It also required some super sharp razor blades positioned to cut the restraining cords at the exact right time. The razor blades would have to resist corrosion for the duration of the mission.

Viggo's back-yard wind tunnel was driven by a souped-up auto engine. He fought the zoning commission to be allowed to keep the structure once they were aware of it.

The scientists and engineers at NASA were amazed that Viggo, who had no college degree, could come up with such a solution. They were doubtful at first, but when shown how it worked, were instead amazed.

They put a team of scientists and engineers to work to validate the theory. They also contracted with the Buck Knife people to assist in making the razor blades to cut the cords. They developed a special steel, corrosion resistant, that would hold an edge so sharp that the effort to cut the cords was almost non-existent.

I was one of the machinists that were tasked to make the razor blades. It involved a lot of hand work, filing the blades into shape. Using machines to shape the blades created too much heat and spoiled the blade. Several of the machinists working on the task asked for and were given a blank to make themselves a knife with. We worked on our own knives during lunch and at night. My knife took 6 months to make.

The test for a sharp knife is to see if it will cut a newspaper page without tearing it. Our knives could cut a newspaper page while held exactly perpendicular to the paper with two fingers, letting the weight of the blade carry it down. There was no rough edges on the paper and it cut silently. We learned to put brass rivets in the scabbards we made after one guy had his knife cut out of the scabbard and lay open his pants and underwear.

All of this comes rushing back watching this video. I replayed the parachute deployment several times, just to enjoy it.

Every aspect of the landing has as much effort and attention to detail put into it. Viggo was a genius, but so were countless other people who contributed to this remarkable effort. I applaud them all.

[jamshundred]

Fascinating story Gene!  Here's another one.  SECRET CODE in parachute canopy.   By the way, did you work at NASA, Greenbelt? 


CAPE CANAVERAL, Fla. (AP) — The huge parachute used by NASA’s Perseverance rover to land on Mars contained a secret message, thanks to a puzzle lover on the spacecraft team.



Systems engineer Ian Clark used a binary code to spell out “Dare Mighty Things” in the orange and white strips of the 70-foot (21-meter) parachute. He also included the GPS coordinates for the mission's headquarters at the Jet Propulsion Laboratory in Pasadena, California.



Clark, a crossword hobbyist, came up with the idea two years ago. Engineers wanted an unusual pattern in the nylon fabric to know how the parachute was oriented during descent. Turning it into a secret message was “super fun," he said Tuesday.



Only about six people knew about the encoded message before Thursday’s landing, according to Clark. They waited until the parachute images came back before putting out a teaser during a televised news conference Monday.



It took just a few hours for space fans to figure it out, Clark said. Next time, he noted, “I’ll have to be a little bit more creative.”





“Dare Mighty Things” — a line from President Theodore Roosevelt — is a mantra at JPL and adorns many of the center's walls. The trick was “trying to come up with a way of encoding it but not making it too obvious," Clark said.



As for the GPS coordinates, the spot is 10 feet (3 meters) from the entrance to JPL's visitor center.



Another added touch not widely known until touchdown: Perseverance bears a plaque depicting all five of NASA's Mars rovers in increasing size over the years — similar to the family car decals seen on Earth.



Deputy project manager Matt Wallace promises more so-called hidden Easter eggs. They should be visible once Perseverance's 7-foot (2-meter) arm is deployed in a few days and starts photographing under the vehicle, and again when the rover is driving in a couple weeks.



“Definitely, definitely should keep a good lookout,” he urged.

[genebo]

I worked my entire career at NASA, Langley Research Center, Hampton, VA. Langley was the first, original site of the NACA (National Advisory Committee for Aeronautics) in 1917. It was converted to NASA (National Aeronautics and Space Administration) on October 1, 1958, the date I entered on duty there.

[jamshundred]

new video