This past week has seen the Mars helicopter Ingenuity successfully deployed onto the surface of Mars in readiness for its first flight – although NASA has announced the flight itself has been delayed.
As I noted in my previous Space Sunday report, the helicopter was unpacked over several days (the work actually commencing prior to that report appearing). It took several days because each stage of the deployment had to be verified to ensure it had been correctly completed using the WATSON camera on the rover’s robot arm imaging the helicopter from several angles after each phase of the deployment so that engineers on Earth could confirm everything looked correct. However, everything went as expected, and by March 31st (UTC), Ingenuity was in an upright position under the rover, but still connected to it via the power umbilical and backplane support.
At this point proceedings were paused whilst systems were given a final check-out prior to the command being given to release the helicopter to drop the 10-13cm down onto the Martian surface. Once released, Ingenuity would be on its own power-wise, with a limited period in which to charge up its batteries using sunlight, so the engineering team wanted to run through final verification that everything was OK.
On Sunday, April 4th, the Jet Propulsion released images revealing that final step of deployment had been completed, and Ingenuity is standing on Mars, Perseverance having moved several metres away to establish line-of-sight communications with the helicopter.
The next challenge is to ensure the solar cells that the very top of the rotor mast are able to provide energy to the batteries, which can only survive 25 hours without recharge now Ingenuity has been separated from the rover.
It had been hoped that the first in a sequence of five planned flight tests would commence on Thursday, April 8th. However, this has now been delayed until Sunday, April 11th, at the earliest.
The delay is to allow for a full regime of tests to be carried out on the helicopter – which has gained the nickname “Ginny” among the engineering and flight team at JPL – including its ability to survive the harsh cold of Martian nights and then recharge its batteries during daylight hours. Should all go according to plan, Perseverance will capture the flight, and images / video from both the rover and the helicopter will be released on or shortly after April 12th.
Providing the first straight-up-hover-straight-down flight is a success, the flight team will move on to the remaining four pre-flights for the helicopter, which the hope to complete well inside the 30-day window allowed for the tests – and potentially complete more, if there is sufficient time left before Perseverance must turn to its now duties and say “bye-bye” to Ingenuity.
When it does commence its own science work, Perseverance may not initially travel too far from the helicopter’s flight zone: whilst Ingenuity was unfolding beneath it, the rover’s team became increasingly intrigued by a green-tinted rock a short distance away.
The yet-to-be-dubbed rock is thought to be a possible meteorite or a piece of bedrock that may have been “popped” up from under the layers of sedimentary rock on which the rover is parked. However, the science team will not be drawn on any conclusions until Perseverance has had the chance to get up close to the rock and focus all of its attention on it. Thus far, the rover has only been able to image the rock using its Mastcam-Z system and zap it a few times with the SuperCam laser system.
That the rock – roughly 15 cm in length – might be a meteorite is not beyond the bounds of possibility: Perseverance’s “sister” rover, Curiosity, happened upon a similar odd rock sitting on the landscape in 2014. Once its duties watching over Ingenuity have ended, Perseverance will be able to devote its full attention on the rock, further utilising its SuperCam laser and spectrometer, as well as the SHERLOC and WATSON combination on its robot arm in an attempt to decipher the rock’s mystery.
Meanwhile, and half a world away, Curiosity has been busy as it continues its investigations of “Mount Sharp”, the 6 km high mound of deposits left in the centre of Gale Crater, the result of multiple periods of flooding.
At the start of March, Curiosity commenced it most recent science campaign, examining an impressive 6 metre high rock formation dubbed “Mont Mercou” after a mountain in France close the village of Nontron, which is being used to generate monikers for features in the area the rover is exploring due to the presence of nontronite, a type of clay mineral (also named for the village) within the area.
The area where the mount is located is of particular interest, as it marks a transitional zone between “clay bearing” and “sulphate bearing” rocks, and thus might contain clues concerning the planet’s transition from the warm, wet world to the frigid desert we see today.
While examining the formation and the rocks around it, including gathering samples via its drill for detailed analysis using the on-board science suite, Curiosity also paused take 71 images using the MAHLI camera on its robot arm and its Mastcam system to create a “selfie” taken against the backdrop of “Mont Mercou”.
Yep, the EmDrive is Impossible
In 2016, I covered the controversial radio frequency (RF) resonant cavity thruster, or EmDrive (pronounced “M-drive”), supposedly the world’s first working reactionless drive; that is, generating thrust without the use of any propellant. In this case, by reflecting microwaves in a conical cavity.
First proposed by British engineer Roger Shawyer in 1999, the EmDrive has generally been considered a violation of the fundamental law of conservation of momentum (summed up in Newton’s third law, “for every action, there is an equal and opposite reaction”).
However in 2016 a team from NASA’s Eagleworks developed a prototype drive and a methodology for testing it that gained peer review approval from the Journal of Propulsion and Power, a publication maintained by the American Institute of Aeronautics and Astronautics (AIAA). The Eagleworks team later claimed their test rig recorded minute, but recordable levels of thrust.
Their results came in for considerable scepticism, particularly as no-one else could reproduce their results. Now a team from Dresden University of Technology has finally shown the EmDrive doesn’t work. appear to have definitively prove the drive does not work.
Contacting Eagleworks, the Dresden team persuaded them to provide the prototype that apparently generated thrust, and the mechanism used to measure that thrust.Using the same set-up as defined by the Eagleworks team, the Dresden team did indeed obtain the same results; the drive appeared to generate thrust.
However, after multiple tests with small configuration changes in the test rig, all of which failed to register thrust from the drive, the Dresden team realised what was happening. The Eagleworks test inadvertently directed heat from the drive’s microwave generator onto the measuring plate’s fastenings. These were then expanding very minutely in response – but enough to change the zero point for the plate, giving the illusion “thrust” was pushing it.
So based on these results, which have also been subjected to full peer review, it would appear the sceptics (and Newton) were correct, and the EmDrive can now be laid to rest.
Bang Goes SpaceX Starship SN11
On Tuesday, March 30th, SpaceX attempted to complete the much anticipated flight of Starship SN11.
In terms of observing the flight, the day was far from ideal, the Boca Chica, Texas, site being shrouded in thick fog. However, the vehicle lifted-off on schedule – 13:00 UTC – cameras on and within it recording the ascent.
Will the ascent was visually smooth, a camera mounted within the engine skirt caught a flash of fire around the turbo pumps of one of the Raptor engines. While pundits brushed this off as “usual” for the vehicle, SpaceX CEO Elon Musk later confirmed one of the Raptor engines – No. 2 – “had issues” during the ascent.
Nevertheless, the flight followed the usual envelope, the only mishap being a brief shot from inside the liquid methane tank that made its way into the official SpaceX stream, possibly in error.
As expected, two of the motors shut down in an orderly sequence to leave just one to push the vehicle the remaining few hundred metres to 10 km altitude before helping to pitch it over into the usual horizontal skydive. This continued down to around 2 km above ground – where things went badly wrong.
At this point, all three engines should have re-lit to allow the vehicle to perform a “flip up” manoeuvre in readiness for a tail-first landing. What actually happened is unclear; engine No. 1 certainly lit up okay – but almost immediately afterwards, all images and data from the vehicle ceased. At that point, cameras on the ground recorded a bright flash lighting up the fog from above before debris started raining down.
The debris from the vehicle fell over a substantially wide area that included the Boca Chica launch and landing site, the road running alongside it (closed to traffic throughout the flight test) and the surrounding land.
Given this, the Federal Aviation Authority (FAA) may be prompted into a more extensive investigation than seen after the landing failures of SN8 through SN10 in order to ensure safety parameters were not breached. If so, this may delay SpaceX in its plans to roll SN15 out to a launch stand as soon as final stacking has been completed and the debris around the launch site has been cleared up.
In Brief
VSS Imagine Rolls Out
On March 30th, Virgin Galactic rolled-out the first of its SpaceShip III sub-orbital space planes. Christened VSS Imagine, the vehicle is visually identical to the company’s SpaceShip II VSS Unity, but is actually the first of a new generation of the craft that include updates that will provide for faster post-flight inspection, maintenance and turn-around of the vehicles, thus allowing a higher cadence of flights once operations commence to fly six passengers at a time to sub-orbital space and back.
Unity and Imagine are two-pilot, six-passenger space planes designed that are carried aloft by their mothership to be released at 15,000 metres, allowing the vehicle’s single rocket motor to power it up to sub-orbital space, before returning to Earth and landing like a conventional aircraft.
Inspriation4 Team Announced
In February, I wrote about Jared Isaacman, the billionaire entrepreneur who plans to head-up the first “all civilian” orbital space flight using a SpaceX Crew Dragon vehicle. Called Inspiration4, the flight is designed to both inspire people about human space flight and to raise money for St. Jude Children’s Research Hospital in Memphis, Tennessee (see: Space Sunday: crashes, tests and an Inspiration).
In announcing the flight, Isaacman indicated he would occupy the commander’s seat, one would be occupied by someone connected to St. Jude’s – in this case, Hayley Arceneaux, a 29-year-old survivor of childhood bone cancer and who now works at the hospital, with the remaining two offered through a competition organised in conjunction with Isaacman’s company Shift4Shop, and via a raffle open to people encouraged to donate to the hospital.
On March 30th, the winners of those remaining two seats were announced at an Inspiration4 / SpaceX event at NASA’s Kennedy Space Centre, along with Isaacman and Arceneaux. They are: 51-year-old Sian Proctor, the winner of the entrepreneurial competition held in conjunction with Shift4Shop, and Chris Sembroski, a 41-year-old data engineer for Lockheed Martin, who didn’t actually win the raffle (although he entered and did donate to St. Jude’s) – but his friend did, and decided to pass the ticket on to Sembroski.
The four will spend three days orbiting the Earth at an altitude 130 km higher than the International Space Station aboard a specially-adapted Crew Dragon which will have a large copula for observing the Earth installed instead of the usual airlock used when the vehicle is docked with the ISS. In the process, the four will perform various experiments and set several records, both as individuals and together, including flying on the first space mission without a professional astronaut on board.
Inara Pey: Living in a Modemworld 