Space Sunday: an evacuation and astronaut health

The International Space Station as it appeared from a Crew Dragon vehicle in 2021. Credit: NASA / SpaceX

For the first time in the history of the International Space Station (ISS), NASA is curtailing an entire crew rotation in order to bring an astronaut with an undisclosed medical condition back to Earth in order for them to receive full and proper treatment.

Exactly what the medical issue is has not been disclosed, although NASA has confirmed it is not injury related and the move is being made out of an abundance of care rather then the crew member suffering any immediate threat to their life. Nor has the name of the affected astronaut been made public as yet. What is known is the affected individual is one of the four people making up the Crew 11 (NASA ISS Expedition 73/74) mission, who arrived aboard the ISS in August 2025, and who were due to return to Earth later in February 2026 following a hand-over to the upcoming Crew 12 mission.

Crew 11 comprises veteran NASA astronaut Michael “Mike” Fincke, who took over the role of ISS commander after arriving there in August 2025, NASA astronaut Zena Maria Cardman, making her first trip into space and who is serving as the station’s Flight Engineer, together with Kimiya Yui of the Japan Aerospace Exploration Agency (JAXA) on his second mission to the ISS, and Russian cosmonaut Oleg Platonov, on his first flight to orbit.

The Crew 11 / NASA Expedition 73/74 crew, clockwise from top rear: Roscosmos cosmonaut and Mission Specialist Oleg Platonov; JAXA (Japan Aerospace Exploration Agency) astronaut and Mission Specialist Kimiya Yui; NASA astronaut (and Crew 11 Commander) Zena Cardman; and NASA astronaut (and Crew 11 Pilot) Mike Fincke. Credit: NASA.

For Cardman this is the second time in succession her debut space flight his been the focus of changes; originally, she was to have flown as part of the Crew 9 mission in 2024, but was removed from that flight alongside astronaut Stephanie Wilson so their positions could be used to return Barry Wilmore and Sunita Wilson to Earth, following the issues with their Boeing Starliner which caused NASA to elect not to use that vehicle to bring them back to Earth.

News of the medical issue first broke on January 7th, when NASA announced the first EVA “spacewalk” of 2026 had been cancelled. This was to have been the first of 4 EVAs carried out by Crew 11 and the upcoming Crew 12 missions to install the last pair of iROSA solar arrays on the ISS as part of a years-long operation to boost the station’s power generation capabilities.

When originally launched, the ISS was furnished with eight pairs of massive 1-tonne solar arrays, each measuring 35 metres in length and 12 metres in width and originally capable of generating some 31 kW of electricity per pair. Called Solar Array Wings (SAWs) by NASA, these massive arrays have slowly become less and less efficient in generating electricity for the station, both as a result of their increasing age and because they are fairly fragile, and some have suffered certain amounts of damage over the decades.

A close-up view of damage done to the 4B SAW of the ISS in 2007, following a move and redeployment of the array during STS-120. Credit: NASA

Initially developed for NASA deep space missions, ROSA – Roll-Out Solar Arrays – are much more compact, much lighter and more robust than the SWs, as well as being far more efficient. The version used on the ISS – iROSA – for example, masses just 325 kg per array, with each array being half the size of the SAW units and able to generate up to 2/3rd the original SAW output. Since 2022, pairs of these iROSA units have been added to the ISS to supplement the SAW units, both stabilising and boosting the station’s power generation capabilities significantly.

As the medical issue was first announced at the time the EVA crew – Fincke and Cardman –  would have been going through personal and equipment check-outs in advance of the actual EVA preparation and execution period planned for January 8th, initial speculation was that one of them had suffered some form of medical issue severe enough to curtail the planned activity. However, speculation as to who the affected crew member might be shifted to JAXA astronaut Kimiya Yui after a press briefing on January 8th revealed that he had requested a private consultation with medical experts on Earth around the same time as the EVA pre-prep work.

Whoever the individual affected is, the result is the same: as they require evacuation to Earth as a matter of safety and well-being, then all four members of Crew 11 must return early from the ISS, so that no-one ends up (dare I use the term beloved of the media?) “stranded” on the ISS “without a ride home”.

A 2021 enhanced image of the International Space Station showing how it would appear with six iROSA solar arrays deployed over three pairs of the the station’s existing primary arrays. At the time, it was only planned to deploy six of the 8 iROSA units to the ISS, the decision to add the final two being made in 2024. Credit: NASA

Currently, the plan is to return Crew 11 to Earth on the 14th / 15th January, with Crew dragon Endeavour departing the ISS at around 22:00 UTC on the 14th, with splashdown off the coast of California planned for around 08:40 UTC on the 15th. Following recovery, the entire crew will likely be flown to shore-based medical facilities.

As a result of this, the ISS is likely to undergo a period when it is under-staffed, with just three people aboard to run things: US astronaut Christopher Williams, on his first rotation at the ISS, together with cosmonauts Sergey Kud-Sverchkov, who is on his second stint on the ISS and will take over as station commander as from January 12th, and Sergey Mikayev, another ISS rookie. Whilst this is not the first time a reduced crew has operated the station (the last was during the COVID pandemic), the early return of Crew 11 does raise some complications for the immediate future of ISS operations.

The first of these is that without the Crew 11 personnel, the first two EVAs required to prepare the external power systems etc, for the installation of the new iROSA units (which would have been carried out by Crew 12 following their arrival on the ISS in February). Nor can the members of Crew 12 or the other personnel on the ISS simply “slot into” the work Cardman and Fincke were to have performed: each EVA requires specialised training and techniques – and none of Crew 12 nor those remaining on the station have received said training. Thus, the iROSA deploy is liable to be subjected to some delay.

Nor is it clear as to when Crew 12 will be in a position to launch to the ISS and take some of the pressure off of Williams, Kud-Sverchkov and Mikayev. Usually, NASA prefers to launch an outgoing crew several days ahead of a departing crew, so as to allow a formal hand-over one to the next. With Crew 11 now set to return early,it is unlikely such a hand-over will be possible, and as a result, additional time will be required by Crew 12 to get fully up-to-speed with the overall status of the ISS and the revised work schedule for their rotation.

A major determining favour in this could be that of Artemis 2. Under the current launch schedule, the SLS rocket for that mission is set to roll-out to Launch Complex 39B at Kennedy Space Centre on January 17th. Once there, the vehicle will undergo the last remaining tests required to clear it for a planned February 6th, mission lift-off.

Like Artemis 1 in 2022 (see here), Artemis 2 is due to make the drive from the Vehicle Assembly Building at NASA’s Kennedy Space Centre to Launch Complex 39B mounted on its Mobile Launch Platform atop NASA’s huge Crawler Transporter. The multi-hour roll-out is currently targeting January 17th, 2026. Credit: NASA

Given this, and while ISS and Artemis missions are essentially separate entities with no real cross-over, NASA is likely to be very cautious about having any parallel launch preparations going on at the “neighbouring” Launch Complex 39A, where SpaceX operate all of their crewed launches, simply because both facilities have a degree of overlap in the use of launch support services – notably radar and tracking capabilities which could bring preparations for both launches into a degree of conflict, particularly if one or the other experiences delays whilst on the pad.

So unless SpaceX is able to demonstrate it is able to accelerate Crew 12 launch preparations to a point where an attempt can be made before the Artemis 2 roll-out and launch and without interfering with the final ground tests Artemis 2 must complete to meet its planned launch date, it is entirely possible Crew 12 will have to wait until around its originally target launch date of February 15th in order to get off the ground. And that’s assuming issues with Artemis 2 don’t push its launch back during a time when Crew 12 could otherwise have been on its pad and otherwise ready to go. As a result, the entire situation remains in something of a state of flux, and this story will continue to develop over the coming week.

Astronaut Health and Welfare

All of the above has forced a degree of focus on the questions of astronaut health and welfare, both on the ISS and in terms of missions to the Moon and Mars. The ISS has the overall advantage in this regard, as it is obviously the closest to Earth, and is the best equipped off-Earth facility when it comes to astronaut health – albeit one that is necessarily limited when it comes to more serious conditions or significant injuries. In particular, the ISS has extensive first-aid and medical facilities, including the likes of an ultrasound scanner, defibrillators and other specialised equipment, with many crew members receiving paramedic levels of medical training, backed by the ability to be able to call on Earthside expertise rapidly and with minimal delay in real-time communications and, in a worse-case scenario, have stricken crew returned to Earth in relatively short order.

While much of this can be replicated in missions to the Moon and Mars, there limitations. Getting back from the Moon is not exactly “immediate”, particularly with regards to the way Artemis using cislunar space rather than a direct Earth-Moon-Earth approach, and Mars is obviously even less so. Further, two-way communications are more limited.; there is always at least a 2.6 second delay in two-way Earth-Moon / cislunar space communications, for example. While this might not sound a lot, it could be the difference between saving and losing a life.

For Mars missions the situation is even worse, given delays are always at least 4 minutes for two-way communications, and can be as much as 24 minutes. Whilst the latter clearly means that practical real-time medical advice and support cannot realistically be offered during medical emergencies, it also means that crews on such mission face the additional psychological strain of being unable to communicate in real-time with family and loved ones, leaving all such contact to pre-recorded messages.

In terms of general health, there are a wide range of issues to be considered. The most obvious is that of physical fitness in micro-gravity conditions: as is only too well-known, long-term exposure to micro-gravity can result in a range of muscular and cardiovascular issues. While these can be addressed through discipline and exercise (around 2.5 hours a day), it’s still a major commitment to do so day in and day out for between 6 and 8 months journey time between Earth and Mars. But whilst such issues are the most referenced of those associated with living and working in microgravity, they they are not the only issues. There are many physiological and psychological matters we have yet to fully understand and address as best we can.

One example of this takes the form of the so-called 2015-16 One-Year Mission (although its duration was technically 11 months). In it, identical twins and astronauts Scott and Mark Kelly where the focus of an in-depth study of physical and psychological impacts of long duration space flight. This saw Scott Kelly spent the time on the ISS, whilst Mark remained on Earth as a control subject. Doing so allowed ten different teams of medical, health and psychology experts to monitor changes in Scott Kelly’s overall health, physiology and psychology using Mark as a baseline reference. Hus, they were able to analyse in detail a wide range of elements and their associated changes in Scott, including body mass changes / redistribution, eye and bone deformation, immune system responses, molecular and psychological changes, alterations in cognitive capabilities and more. The results were in many ways both surprising and unexpected.

Astronauts and identical twins Mark and Scott Kelly after the One-Year Mission (2015/16). Credit: NASA

Whilst Scott Kelly remained in overtly good physical health, he did undergo changes to his cognitive abilities, his DNA and immune system and changes to his body’s gene regulation processes. He also experienced changes to his retinas and eyesight, as well as to his carotids and gut microbiome. Whilst none of these changes were significantly debilitating (and did correct themselves over a period of time following his return to Earth), they were not entirely without outward impact on him, and pointed the way to the potential for serious psychological and other issues being a problem within especially isolated, long-duration missions where direct contact with others outside of the immediate crew is next to impossible in real time.

Nor is this all. As I recently related to friend and fellow space enthusiast Hugh Toussant, there are significant health implications linked to deep space radiation exposure which have only really come to light in the last 6 years and which require much more in the way of study. Some of these issues are, as an example, related to Galactic Cosmic Rays (GCRs), the so-called “background radiation of the Big Bang”, and a subject which has been somewhat overlooked due to a preoccupant with addressing the impact of solar radiation effects such has coronal mass ejections (CMEs) which can admittedly be utterly devastating to an unprotected crew in very short order.

Whilst GCRs perhaps don’t have the immediate threat of something like a CME, they are also potentially much more of a risk over time and harder to address, simply because of the amount of energy they contain. In particular, a 2018/19 study demonstrated that GCR collisions with the human body can result in the reactivation of various strains of Herpes viruses which are otherwise generally dormant. These include the relative mild (but sill unpleasant varicella-zoster virus (VZV), which can cause issues such as glandular fever, all the way through to the highly contagious Epstein–Barr virus (EBV). The latter is particularly nasty, as it is very tightly linked to malignant diseases such as cancers (both lymphoproliferative – Burkitt lymphoma, hemophagocytic lymphohistiocytosis, and Hodgkin’s lymphoma – and non-lymphoid malignancies such as gastric cancer and nasopharyngeal carcinoma).

What was particularly unsettling about this study was that not only did it show that viruses like EBV could be re-activated by exposure to GCRs – but that it had happened to astronauts aboard the ISS, which operates within the relative shelter of Earth’s magnetic field and the protection it offers by diverting GCRs away towards the polar regions and thus out of the path of the ISS as it orbits the Earth.  In particular a check back across the medical histories of 112 astronauts who flew on the ISS and shuttle missions revealed that between 61% and 96% of them had demonstrated shedding one or more re-activated Herpes viruses, including both EBV and VZV.

Exactly how much risk of such viral reactivation might occur on something like a mission to Mars – which largely takes place outside of any protection afforded by Earth’s magnetic field – is utterly unclear. However, given the potential for something like EBZ to give rise to a host of long-term malignant illnesses, it is clear that the apparent link between GCRs and the reactivation and shedding of such viruses needs to be more fully understood in order to enable proper mitigation techniques to be developed well before anyone starts mucking about with trying to send people to Mars.  All of which is a long way of saying that while we have learned a lot about living and working in space, we very much have much more to understand.

Space Sunday: to orbit, to orbit!

An enhanced image of the International Space Station showing how it will appear when six iROSA solar arrays have been deployed over three pairs of the the station’s existing primary arrays. Credit: NASA

It’s getting to be another busy period at the International Space Station, with a lot of comings and goings, together with the on-going upgrade work.

In June, NASA / SpaceX launched the CRS-22 resupply mission to the station carrying 3.2 tonnes of equipment and supplies. A part of that cargo comprised a pair of new “roll out” solar arrays (i.e. they are stowed as a tube, and then unfurled when mounted on the space station). Their arrival marked the start of a major plan to completely overhaul the station’s power generation capabilities by supplementing the current arrays.

Referred to as iROSA, the new arrays were installed over pairs of existing panel which have been getting steadily less efficient in converting sunlight into electrical power. Once the work has been completed – there are two more pairs of iROSA arrays to be delivered in upcoming resupply missions – the station’s ability to produce electrical power via sunlight will be increased to ~215 Kilowatts, well about the  ~160 Kilowatts needed to power it at the moment.

How the ISS looked after the departure of the CRS-22 Cargo Dragon. Credit: NASA

The CRS-22 Dragon vehicle actually departed the ISS on July 10th, leaving two Russian Progress resupply vehicles (77/MS-16 and 78/MS-17), the Soyuz MS-18 crew vehicle and the Endeavour Crew-2 Dragon vehicle docked at the station.

On July 21st, the Crew Dragon Endeavour, which carried NASA astronauts Shane Kimbrough and Megan McArthur and Thomas Pesquet and Akihiko Hoshide (ESA and Japan’s JAXA respectively) to the station, also undocked, but not to return to Earth. Instead, it was piloted around the station to be re-attached to the International Docking Adaptor 3 port vacated by the CRS-22 Cargo Dragon, in order to make way for the upcoming CST-100 Starliner test flight to the ISS, of which more below.

Caught from a camera on the ISS, Crew Dragon Endeavour, with its nose cone open to expose the forward docking mechanism and hatch, makes a soft dock at the IDA-3 docking port of the ISS, July 21st, 2021. Credit: NASA

The next ISS launch to take place came out of Russia on July 21st, when a Proton-M booster lifted off from the Baikonur Cosmodrome at 14:58 UTC, carrying the Nauka Multipurpose Laboratory Module (MLM) on its way to the station.

Designed to provide dedicated space for Russian activates on the ISS, the 20-tonne module – the largest component of the ISS built and launched by Russia, combines additional living space with working space, cargo storage, a dedicated external robotic arm courtesy of the European Space Agency, and attitude control system to supplement those already on the station. It is also around 14 years overdue, having originally been intended for launch in 2007 – and parts of it are approaching 30 years of age, having been originally built in the 1990s as the Functional Cargo Block-2 (FGB-2), built alongside the station’s Zarya module.

A Proton-M lifts-off on July 21st carrying the Nauka MLM on its way to the ISS. Credit: Roscosmos

Following a 9-minute ascent to orbit, Nauka successfully detached from the booster’s upper stage and deployed its solar panels and communications arrays at the start of an 8-day flight to rendezvous and dock with the ISS. This lengthy rendezvous being designed to allow ground engineers to carry out a range of checks ahead of the module reaching the station.

After the launch, reports circulated that the module had encountered assorted problems with its automatic docking system, various sensors and its motors. Neither Roscosmos nor NASA have commented on these reports, other than Roscosmos stated the module was in a safe orbit, and there has been no change in the planned rendezvous and docking date of July 29th.

British skywatcher Martin Lewis snapped this picture of Nauka passing over southern England some 6 hours after launch. Credit: SkyInspector
Ahead of that, the Progress 77/MS-16 vehicle will depart the station, taking the Russia Pirs docking / mini- science module with it. Once clear of the station, the Progress vehicle will de-orbit, burning up in the atmosphere with the 20-year-only Pirs. The module has already been subject to an EVA by Russian cosmonauts on the ISS, who severed all non-essentially connections to the module and ensured it was ready for the undocking manoeuvre.

The undocking / detachment had originally been scheduled for Friday, July 23rd, but was postponed for twenty-four hours, ostensibly to give the the Russia crew on the station more time in which to complete tasks in preparation to detach Pirs. As it is, the undocking / detachment is now expected to occur on Monday, July 26th.

The Nauka MLM being prepared for launch integration. Credit: Rsocosmos

CST-100 Demo 2 Set To Launch

Boeing’s CST-100 Starliner is ready to make its second attempted to make an uncrewed rendezvous with the ISS.

If all goes according to plan, the flight will commence at 18:53 UTC on Friday, July 30th, 2021 when an Atlas V rocket will lift-off from Space Launch Complex 41 at Cape Canaveral Space Force Station in Florida. once in orbit, the capsule – which will be used alongside the SpaceX Crew Dragon to ferry crews to / from the space station – will be put through a series of tests prior to performing an automated rendezvous and docking with the ISS.

The flight – called Orbital Flight Test 2 (OFT-2), comes after an 18-month delay in the Starliner programme, in part the result of the OFT-1 having to be aborted without any rendezvous and docking with ISS after a software issue caused things to go slightly awry, although the capsule did make a successful return to Earth an landing (see: Space Sunday: Starliner’s First Orbital Flight).

The CST-100 Starliner due to fly the OFT-2 mission is moved from Boeing’s vehicle preparation facilities at Kennedy Space Centre ahead of integration into its United Launch Alliance Atlas V launch vehicle. Credit: Greg Scott

Following that flight, an extensive review of Boeing / NASA CST-100 flight operations resulted in a wide-ranging series of recommendations being made, including that of a second uncrewed test flight and rendezvous.  Originally, it had been hoped OFT-2 could be completed by the end of 2020, but several factors – including the SARS-CoV-2 pandemic – put paid to that. Even so, while “late”, the July 30th target launch date is ahead of the August / September period NASA had been looking at.

After launch, the Demo-2 flight should see the capsule reach its initial orbit some 31 minutes after lift-off, allowing the initial in-flight tests to be carried out under the eyes of ground control. After this, the vehicle will proceed to catch-up and rendezvous with the ISS, with docking scheduled for `9:06 UTC on Saturday, July 31st.

If all goes well, I’ll have an update on the flight in my next Space Sunday update.

Continue reading “Space Sunday: to orbit, to orbit!”

Space Sunday: minerals, ice, rockets and capsules

CuriosityNASA’s Curiosity rover has resumed its long, slow climb up the slopes of “Mount Sharp”, the 5 km high mound abutting the central impact peak of Gale Crater on Mars.

For the last few months, the rover has been easing its way over what is called the “Murray Formation”, a transitional layer marking the separation points between the materials deposited over the aeons to create the gigantic mound, and the material considered to be common to the crater floor. Named in honour of the late co-founder of The Planetary Society, Bruce Murray, the formation comprises a number of different land forms, which the rover has been gradually examining.

On June 4th, 2016, Curiosity collected its latest set of drilling samples – the 11th and 12th it has gathered since arriving on Mars – on the “Naukluft Plateau”, a further region of sandstone within the Murray Formation, similar to the area dubbed the “Stimson Formation”, where the rover collected samples in 2015.

The Murray formation extends about 200 metres (650ft) up the side of "Mount Sharp". Starting at the "Pahrump Hills" below "Murray Buttes" in late 2014, Curiosity is about one fifth of the way across the region, spending extended periods examined various features within the formation. Credit: NASA JPL
The Murray formation extends about 200 metres (650ft) up the side of “Mount Sharp”. Starting at the “Pahrump Hills” below “Murray Buttes” in late 2014, Curiosity is about one fifth of the way across the region, spending extended periods examined various features within the formation. Credit: NASA JPL

The aim is to carry out comparative geology between the two sites to determine whether or not their formation is related. The “Stimson Formation” sandstone strongly suggested it has been laid down by wind after the core slopes of “Mount Sharp” had been laid down by sedimentary processes the result of Gale Crater once being home to s huge lake, but which had then been subjected to fracturing by the passage of water. These bands of fractured sandstone have become more prevalent as the rover has continued up through the “Murray Formation”, so it is hoped that by obtaining samples from “Naukluft Plateau”, the science team will gain further understanding of precisely what part water played in the evolution of the slopes of “Mount Sharp” after the lake waters had receded.

The HiRise imaging system on the Mars Reconnaissance Orbiter (MRO) captured the the Mars Science Laboratory rover Curiosity on the Naukluft Plateau in May 2016 (credit: NASA/JPL / University of Arizona)
The HiRise imaging system on the Mars Reconnaissance Orbiter (MRO) captured the Mars Science Laboratory rover Curiosity on the Naukluft Plateau in May 2016 Credit: NASA/JPL / University of Arizona

Since completing the drilling operations, Curiosity has turned south, and is now climbing the mound “head on”, rather than gradually zig-zagging its way upwards.

The MSL rover has also provided geologists with another surprise. In mid-2015, the rover collected samples from a rock dubbed “Buckskin”. Reviewing the analysis of the minerals in the samples, as discovered by Curiosity’s on-board laboratory suite, scientists have found significant amounts of a silica mineral called tridymite.

“On Earth, tridymite is formed at high temperatures in an explosive process called silicic volcanism. Mount St. Helens, the active volcano in Washington State, and the Satsuma-Iwojima volcano in Japan are examples of such volcanoes,” said Richard Morris, a NASA planetary scientist at Johnson Space Centre. “The tridymite in the Buckskin sample is thought to have been incorporated into “Lake Gale”  mudstone as sediment from erosion of silicic volcanic rocks.”

The find is significant because although volcanism did once take place on Mars, it has never been thought of as being silicic volcanism, which is far more violent that the kind of volcanism associated with the formation of the great shield volcanoes of the Tharsis Bulge and other regions of Mars. So this discovery means geologists may have to re-think the volcanic period of Mars’ early history.

China Launches Long March 7

Saturday, June 25th saw the inaugural launch of China’s Long March 7 booster, a vehicle I wrote about back in April 2016. The launch was also the first from China’s fourth and newest space launch facility, the Wenchang Satellite Launch Centre, located on Hainan Island, the country’s southernmost point.

The Long March 7 is a core component to China’s evolving space ambitions. Classified as a medium lift vehicle, it can carry around 13.5 tonnes to low Earth orbit (LEO), it will operate alongside China’s upcoming heavy lift launcher, the Long March 5. This craft will be capable of lifting around the same payload mass directly to geosynchronous orbit, and around 25 tonnes to LEO. Both vehicles will play a lead role in China’s plans to expand her explorations of the Moon, establish a permanent space station in Earth orbit by 2022, and reach Mars with automated missions.

China's Long March 5 (l) and Long March 7 (r) next generation launch vehicles
China’s Long March 7 (right) launched on it inaugural flight on Saturday, June 25th. The bigger Long March 5 (left) is due to launch later in 2016. Credit: China state media

The inaugural launch of the Long March 7 took place at noon GMT on Saturday, June 25th (20:00 local time). It carried a Yuanzheng 1A upper stage and a scale model of China’s next generation crewed orbital vehicle into an orbit of 200 km (120 mi) by 394 km (244 mi) as confirmed by US tracking networks.

Yuanzheng is an automated “space tug” China has used numerous times to deliver payloads to their orbits, and is capable of re-using its engine multiple times. It is most often used to boost China’s communications satellites into higher orbits.

The sub-scale capsule was used to carry out an atmospheric re-entry test to gather data which will be use to further refine and improve the re-entry vehicle which will form a part of China’s replacement for its ageing, Soyuz-inspired Shenzhou crew vehicle. This unit returned to Earth, landing in a desert in Inner Mongolia on Sunday, June 26th, after orbiting the planet 13 times. Also aboard the vehicle was a “cubesat” mission to test a navigation system, and a prototype refuelling system.

Continue reading “Space Sunday: minerals, ice, rockets and capsules”

Space Sunday: Martian tsunamis, Indian space planes, Chinese telescopes

Mars as seen from 80 million km (50 million mi): a Hubble Space Telescope image of Mars captured during opposition on May 12th, 2016. Coincidentally, the Arabia Terra, one of the subjects in the report below, is the dark area in the centre of the image,
Mars as seen from 80 million km (50 million mi): a Hubble Space Telescope image of Mars captured during opposition on May 12th, 2016. Coincidentally, the Arabia Terra, one of the subjects in the report below, is the dark area in the centre of the image, together with Xanthe Terra. Cryse Planitia (Plain of Gold) is in the lower part of the light-coloured circular area dipping into the dark mass of Arabia and Xanthe Terra. North is to the top of the image, south to the bottom. Credit: NASA / ESA

It has long been believed that Mars once had oceans which covered most of the northern hemisphere lowlands about 3.4 billion years ago. Radar mapping from orbit has revealed layers of water-borne sediment similar to those found on Earth’s ocean floors, sitting on top of a layer of volcanic rock. In addition, there is strong evidence for an ancient shoreline and coastal areas around the rim of the ocean. The problem is, the evidence for the coastal areas is far from complete, leading to one of Mars’ many mysteries: if the lowlands were once home to a vast ocean, where did the shoreline go?

Alexis Rodriguez of the Planetary Science Institute in Tucson Arizona believes a study she and her colleagues have been carrying out may hold the key: sections of the Martian coastline may have been washed away as a result of massive tsunamis. And when I say huge – I mean waves towering some 120 metres (400ft) into the air.

The northern hemisphere of Mars when it was once home to an world-circling ocean, 3.4 billion years ago
The northern hemisphere of Mars when it was once home to an world-circling ocean, 3.4 billion years ago

The time of the Martian ocean coincides when the end of the period known as the Late Heavy Bombardment, when the planets of the inner solar system were subject to a disproportionately large number of asteroid impacts. Rodriguez and her colleagues have suggested that two particularly large meteoroids smashed into the northern hemisphere during this period, driving the tsunamis and reshaping the ancient shoreline.

The focus of the study is a region on Mars where the Arabia Terra upland region meets the lower-lying Chryse Planitia, and which should form a part of the ancient shoreline. Within it, Rodriguez and her team have identified two separate geological formations which may have been created by two separate tsunami events.

In this image
This set of images show the region where Arabia Terra flows down to Chryse Planitia. In figure A, the red line denotes the original ancient shoreline of the region. The grey area below and to the left of it denotes depositions believed to be the result of the first tsunami, together with outflow channels carved by the receding flood (blue arrows). The black line indicates the much younger shoreline of the region at the time of the second impact, which saw the formation of icy lobes in the region, and the embaying of features by slurry and material deposit by the receding waters. Images B and C focus on the coastal areas of deposition and embayment. Image created by Esri’s ArcGIS® 10.3 software

The older of the two looks every bit like a coastal region struck by a huge wave which deposited boulders over 10 metres across. As the water then receded back into the ocean, it cut large backwash channels through its debris and boulder field, depositing large amounts of surface material back into the ocean. Then, several million years later, the second impact took place.

This later event came at a time when Mars was effectively entering an ice age, and caused not so much massive tidal waves, but huge ice slurries which spread across the landscape, much of it freezing out, forming lobes of ice. The material which did make it back into the ocean also “embayed” older features there, partially burying them in the slurry.

Radar imaging has revealed subsurface large lobes of icy deposits along the outwash plains and channels in the Arabia Teraa / Chryse Planitia abutment, indicative of the study's suggestion that some of the material deposited after the second tsunami event froze out before it could flow back to the ancient sea
Radar imaging has revealed subsurface large lobes of icy deposits along the outwash plains and channels in the Arabia Teraa / Chryse Planitia abutment, indicative of the study’s suggestion that some of the material deposited after the second tsunami event froze out before it could flow back to the ancient sea

The study isn’t conclusive, but does offer up some strong supporting evidence. Rodriguez and her team are the first to admit more research is required before the tsunami hypothesis might be confirmed or refuted. They are now examining other areas where the ancient coastline is “missing” to see if they exhibit similar evidence for tsunami events.

Continue reading “Space Sunday: Martian tsunamis, Indian space planes, Chinese telescopes”

Space Sunday: naming a (dwarf) planet and weather watching on Mars

A revised infographic of the six largest dwarf planets, showing 2007 OR10's revised 3rd place
A revised infographic of the six largest dwarf planets, showing 2007 OR10’s revised 3rd place

While opinions may be in a state of flux over what constitutes a dwarf planet – the recent discoveries around Pluto’s interaction with the solar wind once again highlighting the debate, the fact remains that there are a fair few to be found in the solar system, with the largest five, as traditionally listed in descending order of volume, being: Pluto, Eris, Haumea, Makemake and … 2007 OR10.

These worlds are so small and so far away – in relative terms – that gathering data on them without actually paying them a visit, as we’ve done with Pluto, isn’t easy. In the case of 2007 OR10, this lack of information means it has been left without a name, only a designation related to its year of discovery.

An artist's conception of 2007 OR10. Astronomers suspect that its rosy color is due to the presence of irradiated methane. Credit: NASA
An artist’s conception of 2007 OR10. Astronomers suspect that its rosy color is due to the presence of irradiated methane. Credit: NASA

However, all this might now be changing after data gathered by the Kepler observatory (about which I’ve written in recent Space Sunday reports) has helped reveal the dwarf planet – which orbits the Sun once every 547.5 years – is actually the third largest such body beyond the orbit of Neptune, sitting behind Pluto and Eris, and thus it could be a lot more interesting than first thought.

Up until now, it had been thought 2007 OR10 was about 1280 km (795 mi) in diameter. However, such is the sensitivity of Kepler’s instruments in measuring light variations whilst seeking extra-solar planets orbiting nearby stars, that the observatory has been able to precisely measure variations in the brightness of this unusually dark little world. These measurements, combined with data obtained from the Herschel Space Observatory, suggest that 2007 OR10 is around 1535 km (955 mi) in diameter, or about 255 km (160 mi) larger than previously thought.

2007 OR10The upshot of this is the dwarf planet is liable to be a far more interesting place than previously thought, potentially covered in volatile ices of methane, carbon monoxide and nitrogen, and may even be somewhat active as a result of its interaction with the solar wind. It also means that it is really overdue for a decent name.

According to convention, the honour of naming it goes to the planet’s discoverers, in this case Meg Schwamb, Mike Brown and David Rabinowitz. They discovered it in 2007 during a search for distant bodies in the Solar System. In fact, Mike Brown has already suggested a name: Snow White, in recognition of the planet’s ice surface composition.

However, this hasn’t stopped suggestions rolling in from the general public – up to and including, “Dwarfy McDwarfface”, in recognition of the recent public voting on the name for the UK’s new polar research ship.

I have to admit that – and indifference to Mike Brown’s suggestion, which doesn’t take into account 2007 OR10’s likely rusty complexion – my personal favourite suggestion has to be that from Greenwood Space Travel Supply Co (shown above right), which puts forward a very strong case for the name of this little world.  I’m also wearing my Dwarf Planet Pride Day badge with … pride!

Two Years of Weather Reporting on Mars

NASA’s Curiosity rover has completed its second year on Mars – its second Martian year, that is; August 2016 will actually mark the end of its fourth Earth year of operations in Gale Crater. This milestone is important, as it means that the rover has been able to accumulate data on two full cycles of Martian seasons and weather.

Gathering data over so long a period helps distinguish seasonal effects from sporadic events. For example, a large spike in methane in the local atmosphere during the first southern-hemisphere autumn in Gale Crater was not repeated the second autumn; it was an episodic release, albeit still unexplained. However, the rover’s measurements do suggest that much subtler changes in the background methane concentration may follow a seasonal pattern; while measurements of temperature, pressure, ultraviolet light reaching the surface and the scant water vapour in the air at Gale Crater show strong, repeated seasonal changes.

Monitoring the modern atmosphere, weather and climate fulfils a MSL mission goal, supplementing the better-known investigations of conditions billions of years ago. Back then, Gale Crater had lakes and groundwater that could have been good habitats for microbes, if Mars has ever had any. Today, though dry and much less hospitable, environmental factors are still dynamic.

Curiosity’s Rover Environmental Monitoring Station (REMS), supplied by Spain’s Centro de Astrobiología, has measured air temperatures from 15.9o C (60.5o F) on a summer afternoon, to -100o C (-148o F) on a winter night.

Comparing temperatures at Mars’ Gale Crater (lower set of bars) to temperatures in Los Angeles. It shows key differences both in how much colder the Martian site is throughout the year, and also how much greater the difference between daily highs and lows. Mars has only about one one-hundredth as much atmosphere as Earth, and without that thick blanket of atmosphere the air temperature around Curiosity usually plummets by more than  55o C (100o F) between the afternoon high and the overnight low.

Continue reading “Space Sunday: naming a (dwarf) planet and weather watching on Mars”

Space Sunday: BEAM and Kepler, Europa and comets

Euorpa's icy, mineral-stained surface as imaged by NASA's Galileo mission - see bwlow (credit: NASA / JPL)
Euorpa’s icy, mineral-stained surface as imaged by NASA’s Galileo mission – see below (credit: NASA / JPL)

In my last Space Sunday article, I covered the arrival of the BEAM inflatable module at the International Space Station, and the concerns for NASA’s Kepler “planet hunter” space observatory. As there’s been further news on both of these, I thought I’d start this Space Sunday with a quick round-up on them, starting with Kepler.

The Kepler observatory, located some 121 million kilometres (75 million miles) “behind” Earth as both orbit the Sun, has been engaged in a 7-year mission to try to locate planets – particularly possible Earth-type planets – orbiting other stars. As I reported last time around, despite one major setback which called a halt to the observatory’s primary mission in 2012, Kepler has been a remarkably successful mission, catalogue some 4,000 potential planets orbiting other suns, with over 1,000 subsequently confirmed as planets.

However, on April 7th, Kepler reported to mission managers that it has entered Emergency Mode – a status indicating a critical problem has occurred, causing the observatory to shut down all science operations and other systems, and was utilising its supplies of valuable propellant to maintain its orientation so it could communicate with Earth, rather than using its electric reaction wheels, powered by sunlight.

Keler 425b - the first Earth-like planet to be found orbiting within its sun's habitable zone
Keler 425b – the first Earth-like planet to be found orbiting within its sun’s habitable zone (credit: NASA)

Over the next several days, mission engineers were able to upload instructions to Kepler so that it could position itself in a “point rest state” where communications could be maintained without eating into further propellant reserves. Following this, a long, slow data download commenced, which allowed engineers to fully understand the extent of the problem – but not the cause. However, this has been enough for a path to recovery to be determined.

Kpler: being nursed back to health from 121 million km away
Kpler: being nursed back to health from 121 million km away (credit: NASA)

Since April 12th, commands have been sent to the observatory instructing it to bring it non-critical systems back on-line one at a time, monitoring responses as it did so. With each system successfully restored, Kepler has been gradually coming to life whilst eliminating potential causes of the original problem. There is still a way to go, but mission managers are now reasonably confident Kepler can be restored to a fully operational status.

“The recovery started slowly and carefully, as we initially merely tried to understand the situation and recover the systems least likely to have been the cause,” said Kepler programme manager Charlie Sobeck on April 14th. “Over the last day and a half, we’ve begun to turn the corner, by powering on more suspect components. With just one more to go, I expect that we will soon be on the home stretch and picking up speed towards returning to normal science operations.”

Meanwhile, BEAM – the Bigelow Expandable Activity Module – an inflatable prototype habitat module which arrived at the International Space Station on April 10th – was extracted from its ferry vehicle, the uncrewed Dragon resupply vehicle, on Saturday April 16th, and successfully secured against the airlock node of one of the station’s modules.

the extraction and relocation were undertaken remotely, using the space station’s robot arm commanded from Earth to lift the BEAM unit, still in its compact “flight” configuration just 2.4 metres (8ft) in length and 2.1 metres (7ft) diameter, from the unpressurised section of the Dragon cargo vehicle and then position it against the US Tranquillity Module of the space station, where it was secured by astronauts Tim Kopra and Jeff Williams.

Space station commander Tim Kopra took this photograph of the BEAM unit, in its compact state, being moved towards the Tranquillity module by the station's robot arm, ready for it to be secured against one of the station's airlocks
Space station commander Tim Kopra took this photograph of the BEAM unit, in its compact state, being moved towards the Tranquillity module (seen on the left, directly under the robot arm) by the station’s robot arm, ready for it to be secured against one of the station’s airlocks (credit: NASA / Tim Kopra)

The module is not due to be inflated until early May, when it will increase in size to some 4m x 3.5m (13ft x 10.5ft) and provide some 16 cubic metres (565 cubic ft) of working space. It will be equipped with monitoring equipment  to investigate how well it protects against solar radiation, space debris and contamination over a 12-18 month period. During this time, ISS crew members will enter the unit 3 or 4 times a year to collect deployment dynamics sensor data, perform microbial surface sampling, conduct periodic change-out of the radiation area monitors, and inspect the general condition of the module.

BEAM-animation
Animation showing the manoeuvre to position BEAM against the Tranquillity module

Continue reading “Space Sunday: BEAM and Kepler, Europa and comets”