Space Sunday: selfies, missions, budgets and rockets

Zhurong and its lander. Credit: CNSA

You would be forgiven for thinking the banner image for this update is an artist’s impression of China’s Zhurong rover and its lander on Mars. But you’d be wrong – the image really was taken on Mars.

It is part of a batch of images the China National Space Administration (CNSA) have released charting the recent activities of their rover on the Red planet, and they are as remarkable as anything seen with the US rover vehicles, with others showing panoramic views around the rover and shots of its lander vehicle.

The Zhurong lander, part of China’s Tianwen-1 Mars mission., as seen from the rover vehicle at a distance of some 6 metres. Credit: CNSA

Captured on June 8th, the image of rover and lander was taken by a remote camera originally stowed in Zhurong’s belly, and which had been safely deposited on the surface of Mars some 10 metres from the lander, allowing mission control to remote capture the unique sight of a rover and its lander side-by-side.

Zhurong has now completed the first third of its initial 90-day mission on Mars, and is well into its survey of its surroundings within Utopia Planitia. In addition to the high-resolution cameras, used to produce these images, the rover is fitted with a subsurface radar instrument, a multi-spectral camera and surface composition detector, a magnetic field detector and a weather monitor.

A 360 panorama of the Zhurong landing site, captured by the Chinese rover prior to is descent from the back of its lander. Credit; CNSA

Ahead of the images released by CNSA, NASA released their own image of the Chinese rover and lander as seen by the HiRISE camera on the Mars Reconnaissance Orbiter  from an altitude of around 400 km.

Taken on June 6th, three weeks after Zhurong touched-down, the image clearly shows green-tinted lander (a result of the image processing, not the actual colour of the lander) sitting between two areas of surface material discoloured by the thrust of the lander’s outward-angled descent and landing motors. Zhurong itself can be seen a short way south of the lander, within the eastern arc of discolouration.

Captured by the HiRISE imager on NASA’s Mars Reconnaissance Orbiter on June 6th, this image shows the Zhurong lander surrounded by surface material discoloured by the lander’s rocket motors, with the rover sitting just to the south. Credit: NASA/JPL

And turning to NASA’s surface mission on Mars (specifically Mars 2020): on June 8th, the Ingenuity helicopter completed a 7th flight, this one error-free.

Lifting off at around 12:34 local mean solar time (roughly 15:54 UTC on Earth) proceeded south during the 63-second flight, covering a distance of around 106 metres before touching down at a new location.

Ingenuity captured this image of its shadow passing over the surface of Mars on June 8th, 2021 during its 7th flight. Credit: NASA/JPL

In difference to the 6th flight on May 22nd, which saw the helicopter encounter some anomalies (see: Space Sunday: Martian Clouds, Lunar missions and a Space Station), the seventh flight was completed with incident, once again raising confidence that the helicopter will be able to continue flying several more times.

Overlaid onto an image be NASA’s Mars Reconnaissance Orbiter are the routes for the first and second science sorties to be made by Perseverance. Credit: NASA/JPL

Now regarded as fully commissioned, Perseverance has put its duties as caretaker-watcher for Ingenuity largely behind it, as is now driving south and away its landing zone on its way to study a 4 square kilometre of crater floor, where it will examine two very different geological units and collect samples for analysis and for storage and possible return to Earth as part of a future mission.

“Crater Floor Fractured Rough” is a region of ancient bedrock, whilst “Séítah” (Navajo for “amidst the sand”) presents a mix of bedrock overlaid with more recent ridges and also sand dunes. The rover will perform a gentle loop through these areas, visiting “Crater Floor Fractured Rough” first then travelling through the ridgelands and then back up through “Séítah S” and Séítah N”, before heading for its next target, an area dubbed “Three Fours”.

ESA Looks to Venus and the Outer Planets

The European Space Agency has announced its goals for the next several decades in terms of robotic exploration of the solar system and cosmic science.

Announce on June 10th, the EnVision mission will carry a suite of spectrometers, sounders and a radar to study the interior, surface and atmosphere of Venus. The target launch period is May 2032, with the vehicle arriving in orbit around Venus in August 2033, where it will use the planet’s upper atmosphere to aerobrake into its final science orbit over a 3-year period, before commencing its four-year primary mission. It  is expected to cost around 500 million Euros.

ESA plans to further extend our knowledge and understanding of Venus with the EnVision mission, due to launch in 2032. Credit: ESA

While there has been no coordination between NASA and ESA in terms of mission selection, EnVision’s science mission is highly complementary to the two NASA missions – VERITAS and DAVINCI+ – also recently announced, covering aspects of Venus science they do not. Further, ESA will be flying science packages on VERITAS, and NASA will be providing the synthetic aperture radar for EnVision.

EnVision is the fifth M-class mission ESA has selected as part of the Cosmic Vision program. The first, Solar Orbiter, was launched in February 2020, and three others are in development: Euclid, a mission to map dark matter and dark energy to launch in 2022; Plato, an exoplanet search mission launching in 2026; and Ariel, an exoplanet characterisation mission launching in 2029.

In addition To EnVision, ESA intends to spend the next several decades developing  missions to follow after the Jupiter Icy Moons Explorer, that will help assess the habitability of the icy moons in the outer solar system and seek any biosignatures they may have. At the same time ESA intends to support further science endeavours aimed at increasing our understanding of our own galaxy and the likely state and development of the early universe.

Continue reading “Space Sunday: selfies, missions, budgets and rockets”

Space Sunday: Martian clouds, lunar missions and a space station

NASA’s Curiosity Mars rover captured these clouds during the twilight period on March 19, 2021, the 3,063rd Martian day, or sol, of the rover’s mission. The image is made up of 21 individual images stitched together and colour corrected so that the scene appears as it would to the human eye. The clouds are drifting over “Mont Mercou,” a cliff face that Curiosity has been studying on “Mount Sharp”. Credit: NASA/JPL

Clouds are rare on Mars, but they can form, being typically found at the planet’s equator in the coldest time of year, when Mars is the farthest from the Sun in its oval-shaped orbit. However, in 2019 – a year ago in Martian terms – the Mars Science Laboratory team managing NASA’s Curiosity rover in Gale Crater noticed the clouds there forming earlier than expected.

With the onset of winter in the region earlier in 2021, the MSL team wanted to be ready in case the same thing happened, training the rovers cameras on the sky around “Mount Sharp” to catch any evening cloud formations that might appear as the tenuous atmosphere cooled towards night-time temperatures.

Clouds moving over Mount Sharp, as captured by Curiosity on March 19th, 2021. Credit: NASA/JPL

What resulted are images of wispy puffs filled with ice crystals that scattered light from the setting Sun, some of them shimmering with colour. Visible through both the black-and-white lenses of the rover’s navigation cameras and the high-resolution lenses of the Mastcam system, the pictures captured by Curiosity might easily be mistaken for high-altitude clouds here on Earth.

And high altitude is precisely the term to use for this clouds. Most clouds on Mars largely comprise water vapour and water ice. They tend to occur some 60 km above the planet, although they can occur much lower – the massive shield volcano of Olympus Mons, for example, has oft been images with cloud formations around its  flanks, the product of differing atmospheric temperature regimes on the slopes.

However, the clouds seen by Curiosity are believed to be far higher than 60 km in the Martian atmosphere, and are thought to be largely composed of frozen carbon dioxide (dry ice). They occur during the twilight hours – although the mechanism that gives rise to them is not fully understood; but they are thin enough for sunlight to pass through them, catching the ice crystals and causing them to shimmer for a time before the Sun drops below their altitude, causing them to darken. This effect gives them their name: noctilucent  (“night shining”) clouds.

These clouds are best seen in the black and white images captured by the rover’s Navcams, as shown here. However, there is a second form of clouds best seen via Curiosity’s Mastcam colour images. These are iridescent, or “mother of pearl” clouds, rich in pastel colours.

Mother of Pearl clouds spotted by Curiosity in March 2021. Credit: NASA/JPL

They are the result of the cloud particles all being nearly identical in size, something that tends to happen just after the clouds have formed and have grown at the same rate. The colours are so clear, were you able to stand on Mars and look at the clouds, you’d see the shades with your naked eye, and they are another part of the beauty of Mars.

Ingenuity Hiccups During Sixth Flight

NASA’s Mars helicopter Ingenuity encountered some trouble on its sixth flight – the first flight of its extended mission  – on May 22nd.

The flight should have seen the helicopter climb to a height of 10 metres, then fly some 150 metres south-west of its starting point to reach a point of interest where it would travel south for 15 metres, imaging the terrain around and below it for study by scientists on Earth, before making a return to a point close to where it lifted-off.

This image was taken from the height of 10 metres by NASA’s Ingenuity Mars helicopter during its sixth flight on May 22, 2021. Credit: NASA/JPL

The flight was designed to be the first specifically targeted at testing the helicopter’s ability to be used in support of ground operations on Mars, offering the mission team the chance to determine if the area images might be worth a future foray by the Mars 2020 Perseverance rover.

However, 54 seconds into the flight, Ingenuity suffered a glitch that interrupted the flow of images from its navigation camera to its onboard computer. This meant that each time the navigation algorithm performed a correction based on a navigation image, it was operating on the basis of incorrect information about when the image was taken, leading to incorrect assumptions about where it was and what it should be doing.

This lead to Ingenuity pitching and rolling more than 20 degrees at some points during the flight as it struggled to return to its landing zone, post-flight telemetry revealed the helicopter experienced some significant power consumption spikes. However, it maintained its flight and  executed a safe landing just 5 metres from the intended touch-down point.

In a very real sense, Ingenuity muscled through the situation, and while the flight uncovered a timing vulnerability that will now have to be addressed, it also confirmed the robustness of the system in multiple ways. While we did not intentionally plan such a stressful flight, NASA now has flight data probing the outer reaches of the helicopter’s performance envelope That data will be carefully analysed in the time ahead, expanding our reservoir of knowledge about flying helicopters on Mars.

Håvard Grip, Ingenuity’s chief pilot.

Making the Moon a Busy Place

It’s starting to look like the Moon is going to be a terribly busy place. NASA’s Artemis programme is gathering pace in several areas – despite a degree of in-fighting among the principal US contractors – Russia and China have signed an accord that is liable to see them operating in the lunar south pole regions alongside the US-led mission (although the two will remain separate mission entities), whilst Canada and Japan have announced missions to the Moon as a part of the overall Artemis framework, and NASA is seeking ideas from lunar rover vehicles.

The in-fighting revolves around NASA’s April announcement that SpaceX will be granted a sole contract to develop the HLS – Human Landing System – the vehicle that will place humans on the surface of the Moon and return them to orbit. It was a contentious decision; the US agency had previously indicated that two contracts for HLS would be granted, with three players involved: a team led by Jeff Bezos’ Blue Origin, a team led by Dynetics, and the late-comer to the party, SpaceX.

The three proposals for NASA’s Human Landing System vehicles that had been under consideration for the Artemis programme. Left: the Dynetics lander / ascent vehicle; centre: the modified SpaceX Starship NASA has opted for; right: the National Team’s descent / ascent modules. Credit: NASA

There were several leading reasons for the decision – including the matter of cost. However, both Dynetics (potentially with the most flexible approach to HLS) and Blue Origin raised objections with the Government Accountability Office (GAO), which ordered NASA to cease any financial support to SpaceX (worth a total of US $2.9 billion) to the SpaceX effort until it has completed an investigation.

The US Senate has also weighed-in on the subject, with Senator Maria Cantwell (D-Wash.), chair of the Senate Commerce, Science and Transportation Committee, adding an amendment to the Endless Frontier Act which forms the backbone for financing the Artemis programme, requiring NASA put a further US $10 billion into HLS – whilst Senator Bernie Sanders (D-Vermont) went the other way by calling for the cancellation of the entire HLS programme, wrongly characterising it as the “Bezos Bailout”, and so doing what he does best; creating further division and confusion.

As it is, the GAO will release its findings on the matter in August, and while it is hard to ascertain the impact of the delay, it would likely further diminish NASA’s chances of achieving the original goal of a return to the Moon by the end of 2024.

NASA’s Nancy Grace Roman Space Telescope has been targeted for continued financial support by the Biden administration, potentially ending ill-conceived attempts by the previous administration to axe the project.  Credit: NASA Goddard Space Flight Centre / CI Lab

Continue reading “Space Sunday: Martian clouds, lunar missions and a space station”