The 2021 Earth-Sun-Mars conjunction that saw Earth and Mars on opposite sides of the Sun, interrupting all communications between the two, is now over. This means that the multi- national missions on and around the red planet (America, Europe, the UAE, and China) are switching back from automated activities to more regular operations.
China’s Tiawen 1 orbiter and their solar-powered rover surprised mission controllers by calling home earlier than had been anticipated, to report that they are resuming science operations after their enforced semi-hibernation. The wake-ups come in advance of a change in both missions that will be taking place in early November.
At that time, the Tianwen 1 will switch to a new mission phase, a global mapping and analysis of the Martian surface and subsurface with its suite of seven science instruments. This will reduce the opportunities the orbiter has to act as a communications relay for the rover from once a day to once every few days. To help fills the “gaps” when Tianwen 1 is unable to act as a relay, Europe’s long-running Mars Express orbiter is going to attempt to step up to the plate and relay communications between the rover and Earth – pending the outcome of several communications tests to take place at the start of November.
Down on Mars, the Zhurong rover had covered 1,182 metres from its landing platform before going into stand-by mode for the solar conjunction. Since waking up, it has resumed its trip south in Utopia Planitia, and is approaching the end of its second 90-sol period of operations, opening the door for a re-assessment of its science targets. Of particular interest to Chinese scientist are a series of “mud volcanoes” and features that may have been formed by movements of subsurface water and ice, where Zhurong’s ground-penetrating radar is expected to provide “fundamentally new perspectives” on potential subsurface Martian water ice, that might be applied to any development of past life on Mars and on the use of sub-surface water by future crewed missions.
For NASA’s Ingenuity helicopter, the end of the conjunction means a resumption of flight operations following tests to run its contra-rotating propellers at high-than-usual RPM to counter the thinning density of the atmosphere in Jezero crater as winter approaches. This flight was initially scheduled for as early as Saturday, October 23rd, but at the time of writing had yet to be confirmed as having taken place.
Meanwhile, NASA has released a new video showcasing many of the sounds of Mars that have thus far been recorded by Ingenuity’s companion on Mars, the Perseverance rover.
“Percy” carries two off-the-shelf microphones, one mounted on it hull, the other on cover on the camera mounting frame located at the top of its instrument mast. Since the rover’s arrival on Mars, both microphones have been used to record a range of sounds both of Mars and of the rover and Ingenuity operating on the planet.
The Mars 2020 mission is the first to Mars to carry microphones that allow us to listen to the planet – but their inclusion is not merely due to idle curiosity. Listening to the sounds of the planet and the rover can reveal a lot, as mission scientist Nina Lanza, one of those behind the microphone project, explains:
First, we can learn about the atmosphere by understanding how sound propagates through it. We can also listen to the sounds of rover analyses on rocks and learn about rock material properties from that. And finally, we can also listen to the sounds the rover makes to help better understand the state of our instruments.
– Nina Lanza, Los Alamos National Laboratory
Analysis of the sound picked-up from Ingenuity’s rotors, for example, has revealed that sound propagates through the Martian atmosphere a lot different to how it had been believed. Changes in the sound the rover makes during driving and other operations could also help give an early indication of possible problems / mechanical issues, making the microphones invaluable.
With the public hearings into the Federal Aviation Authority’s draft Programmatic Environmental Assessment (PEA) report on the SpaceX “Starbase” production, test and launch facilities in Boca Chica, Texas, now completed, SpaceX continues to push ahead with preparations for its first Starship / Super Heavy test flight and other work critical to that, and future Starship / Super Heavy launches.
The tank farm that will store and deliver propellants and other consumables to the launch facilities has seen the last of its vertical tanks and their concrete sheathing installed. At the same time as this work was progress, a set of horizontal tanks, thought to be intermediary tanks that may be used to hold propellants, etc., when detanking boosters between things like static firs tests, arrived for installation at the farm.
The launch facility itself has most recently seen the assembly and installation of the gigantic “Mechazilla”, the extraordinary mechanism that will both lift Super Heavy boosters onto the launch table and stack Starships on top of them (as well as being able to remove both from the launch facilities) and – eventually – actually “catch” returning boosters and Starships, allowing (in theory) both to be rapidly turned around and re-used whilst eliminating the need for either to have complicated and heavy landing leg systems.
“Mechazilla” will achieve this by travelling up and down the launch support tower on three rails whilst having a “head” that can rotate around three side of the tower, and two huge “chopstick” arms than can open and close around a Super Heavy or Starship vehicle, allowing it to raise or lower them – and eventually catch them as they make a (hopefully) precision return to Earth that brings them down alongside the launch support tower.
The massive system will not be used for the first orbital flight attempt with Booster 4 (currently on the launch table) and Starship 20, but may be used in an attempt to catch Booster 5 (currently under construction as the “next generation” of Super Heavy vehicles) when that launches in 2022. However, captures of Starship vehicles will not be seen for some time.
Also during the past week, Starship 20 has completed a series of static fire tests of its Raptor engines – including the first firing of a Raptor vacuum engine integrated into a Starship vehicle, and the first joint firing of a vacuum engine and a sea-level motor. Some of the vehicle’s heat shield titles were blown off during the tests, but otherwise the firings were viewed as successful.
Such is the progress at Boca Chica that Elon Musk has indicated the company will be ready to make that first orbital flight in November, pending regulatory approval. However, it would seem unlikely this would be granted in time for a November launch. The review period for the PEA doesn’t close until November 1st, and the public hearings mentioned above drew strong feedback both in support of, and against SpaceX’s expansion of the Boca Chica facilities, with the latter focused on already noticeable environmental issues.
After November 1st, the FAA will require time to complete its report, incorporating all of this feedback and a separate report from the U.S. Fish and Wildlife Service. Even if the report is positive, it still has to be reviewed and digested by the arm of the FAA responsible for granting launch licences. Given that November is something of a “short” month in the US due to the Thanksgiving holiday, it seems doubtful the FAA would complete all this work and grant a licence to SpaceX for Super Heavy / Starship flights by the end of the month.