Space Sunday: roadmaps, space stations, rovers and storms

A dramatic illustration from the latest NASA report on reaching the Moon and Mars with human space flights. Credit: NASA

On September 28th, 2018, NASA issued its latest report on how it hopes to return humans to the Moon and then travel onwards to Mars. Entitled the National Space Exploration Campaign Report, it’s a bit of a curate’s egg of things; just 21 pages in length, it offers a lot of aspiration, not always with underlying detail; avoids hard decisions while offering open-ended time lines; presents time lines as a road map,  but avoids mention of precisely how to reach the destination(s) or the cost of the journey(s).

In all, the report lays out three broad aims:  expanding low Earth orbit activities to include commercial operators, operating their own orbital facilities – and possibly the International Space Station; moving outwards to lunar orbit and from there to the surface of the Moon; then moving onwards to Mars. All are painted with very broad brush strokes and leave much unsaid.

LOP-G is now seen as a “foundational gateway” system for reaching both the Moon and Mars – click for full size, if required. Credit: NASA

The lunar aspects of the report, for example, cover the incremental development of the Lunar Orbital Platform-Gateway (LOP-G) and how it could theoretically help develop capabilities that can be used in vehicles intended to carry humans to Mars. It also outlines how NASA can build towards human operations on the Moon through an incremental development of automated capabilities that both increase our understanding of the Moon, the resources it offers, etc., to a point where the first crew-carrying lander vehicle could be ready “in the late 2020s”. But when it comes to detailed ideas for the architecture of a human presence on the Moon, things are left vague.

In terms of Earth orbit operations, the report points to NASA transitioning away from operating the International Space Station to leasing facilities from the private sector; but precisely how these commercial orbital platforms are to be built is unclear, other than referencing the US $150 million of NASA’s that will be used to encourage commercial development of such platforms from 2019. $150 million is a very small amount when you consider the $100 billion construction cost of the ISS; without some very clear-cut, real-time ROI being evidenced for the private sector, it’s hard to see the ISS being supported by multiple commercial platforms of equatable capabilities in just six years.

NASA’s “swoosh” chart outlining the agency’s plans for lunar exploration, and a common element is recent presentations and a part of the new report. Credit: NASA

To be fair, some of the lack of detail within the report is understandable on a number of levels. In 1989, for example, NASA produced the Space Exploration Initiative (SEI), a report outlining how it would take humans to Earth orbit, thence to the Moon and thence to Mars. The report offered a massive vision: 30 years of development and exploration lading up to humans landing on Mars – as a suitable price tag to go with it: US $430 billion. That’s the kind of figure that would have had Congress dropping the report into the bottom of a very deep draw (possibly in a locked filing cabinet stuck in a disused lavatory with a sign on the door saying Beware of the Leopard, somewhere in the basement of Capitol Hill, if I might re-purpose a quote).

There’s also the fact that it’s hard to get any politico to sign up to something that has end results they’re unlikely to be in office long enough to see. This was certainly the case with SEI, and it was something John F. Kennedy understood when he set NASA the goal of “landing a man on the Moon and returning him safely to the Earth” within a decade. Thus, it is perhaps understandable why this report doesn’t stray that far beyond 2024, preferring to leave matters after that date pretty much as “TBD”.

However, in the course of the last few years, NASA has been repeatedly criticised by the US Congress for refusing to present  specifics when outlining its intentions. In this respect, the pendulum seems to have swung too far: from a gung-ho attitude of “gives us the money and we’ll deliver – although it could take longer than you’ll be around” evidenced with SEI, to an almost timid, “We’d like to do this, but we’ll sort out how later, so you don’t have to worry about the price”, which is perhaps as equally as dangerous when trying to set out where you’d like to go and how you’d like to get there.

The View from an Asteroid

In my previous Space Sunday update, I covered the arrival of two small Japanese landers on the surface of asteroid 162173 Ryugu. Since then, both of these little vehicles have been returning images and data as they sit on the asteroid’s surface and / or hop around it.

While the rovers – MINERVA-II1 A and B – have both revealed the surface of Ryugu to be rocky, the images are still stunning, especially those stitched together to form a time-lapse video showing the Sun passing across the sky above rover 1 B as the asteroid tumbles along its orbit.

The rovers are two of four vehicles that will be delivered to the surface of Ryugu by Japan’s Hayabusha 2 satellite, currently orbiting the asteroid. Together the rovers and orbiter will probe and study Ryugu in detail, with the orbiter also gathering samples from both the surface and sub-surface, which it will return to Earth for analysis at the end of 2020.

China’s Space Station Potentially Delayed

China’s plans to establish a multi-module, 60-tonne space station in Earth orbit may be subject to delay, the China Manned Space Engineering Office (CMSEO) has announced.

Artist’s impression of the planned Chinese space station complex. Credit: CCTV

The first element of the station, a 20-tonne module called Tianhe (literally: “Harmony of the Heavens”), had been slated for an early 2020 launch, using China’s most powerful launch vehicle, the Long March 5. Ahead of the launch, China had expected to complete three other Long arch 5 launches, including one of the Long March 5B in 2019.

However, the loss of the second Long March 5 vehicle to be launched, in July 2017, resulted in an extensive redesign of its first stage motors, which may not yet have been cleared for flight. This now means China looks unlikely to get the first of the remaining Long March 5 flights ahead of Tianhe’s launch off the ground in November 2018, as planned. As each launch requires around 3 months of preparation, including 2 weeks just to ship each launch vehicle from the manufacturing centre in Tianjin, north China to the Wenchang launch facilities on Hainan, there may be insufficient time to meet Tianhe’s early 2020 launch date.

A complication here is that Tinahe was to launch ahead of China’s first mission to Mars – an orbiter/lander/rover combination, scheduled for a March 2020 launch. This is a launch that cannot slip, in part because of the 26-month gap between launch opportunities to Mars and in part because its arrival at Mars is timed to coincide with the centenary of the Communist Party of China (CPC), making it a central part of the CPC’s celebrations and a global demonstration of China’s spacefaring prowess.

An artist’s impression of China’s Mars lander, carrying a rover vehicle, arriving on Mars in 2021. The mission could contribute to slippage in the launch of China’s Tinahe space station module. Credit Xinhua

This being the case, it now seems Tianhe may not launch until later in 2020.  

“Oppy” Seen, But Not Heard

With the planet-wide dust storm on Mars now almost completely abated, NASA’s efforts to try to re-establish contact with the Mars Exploration Rover Opportunity are in full swing. The rover – referred to as “Oppy” has been in hibernation mode since early June, when the quantities of dust thrown into the Martian atmosphere reached a point where the rover couldn’t receive enough sunlight through its solar panels to charge its batteries and so needed to conserve power.

It had been hoped that as the storm ended and the skies cleared, “Oppy” would re-establish contact with Earth itself, but this has not been the case, and in early in September 2018, NASA announced that once daily conditions in the vicinity of Endeavour Crater, where Opportunity is located, were suitable for the acquisition of sunlight by the rover to bring itself out of hibernation, a 45-day active campaign to contact “Oppy” would begin.

Those efforts have so far proven unsuccessful, but on Thursday, September 20th, 2018, NASA’s Mars Reconnaissance Orbiter (MRO) passed over Perseverance Valley on the edge of Endeavour Crater, and imaged the site using it high-resolution HiRISE camera system. Taken from an altitude of about 267 km (166 mi), the one image reveals the rover to be sitting exactly where it should be, but remains unresponsive to efforts to contact it.

MER Opportunity sits in the white square, some 467 m on a side, in this images captured by the Mars Reconnaissance Orbiter on September 20th, 2018. Communications with the rover have yet to be re-established. Credit: NASA/JPL / MSSS

The decision to only spend 45 days trying to recover contact with the rover has received wide criticism from former members of the MER mission, who point out that when Spirit, the “twin” rover to Opportunity lost contact with Earth, a 10-month effort was made to try to regain communications.

Titan’s Dust Storms

It’s now just over a year since the NASA / ESA Cassini mission to Saturn and its moons came to an end (read here for more), but the analysis of the data it gathered over it thirteen years in orbit around Saturn continues to be analysed and assessed.

Much of this work has focused on Saturn’s largest moon, Titan. With is dense atmosphere, rivers and lakes of hydrocarbons, evidence of weather systems, Titan is pretty much a world in its own right. Now, a new study of data gathered on the moon reveals it has something else in common with places like Earth and Mars: dust storms.

A team of scientists from across Europe and America have found that data and images captured by Cassini’s Visual and Infrared Mapping Spectrometer (VIMS) not only reveal the turbulent nature of Titan’s atmosphere, but also the fact that local weather patterns can whip-up localised dust storms that can be carried great distances across the face of the moon.

Animation based on the images captured in 2009 by the NASA/ESA Cassini mission shows clear bright spots that have been interpreted as dust storms. Credits: NASA/JPL / University of Arizona / Université Paris Diderot / IPGP

It is believed that, like those of Mars, Titan’s dust storms are the result of seasonal changes. In particular, solar heating  – though weak – is enough to perturbate Titan’s  methane-rich atmosphere as the summer seasons come to both the northern and southern hemispheres, driving winds. When these winds occur close to dunes of organics known to exist along Titan’s equator, they are sufficient to lift material from the dunes up to around 6-10 km (3.75-6.25 mi) up into the atmosphere, and carry them in suspension.

“Titan is a very active moon. We already know that about its geology and exotic hydrocarbon cycle. Now we can add another analogy with Earth and Mars: the active dust cycle, in which organic dust can be raised from large dune fields around Titan’s equator.”

– Sebastien Rodriguez, Université Paris Diderot, co-author of the Titan dust storm study

While this is the first such indication of dust storms being a part of Titan’s natural cycle, it raises intriguing questions and opportunities. Both on Earth and on Mars, dust storms can have widespread impact on weather and climate, while on Earth, they can help distribute organic matter carried aloft by winds. Given the highly organic nature of Titan’s  surface and atmosphere, both of which contain many of the basic building blocks of life, so these storms could have significant implications for our understanding of the dynamics at work in Titan’s atmosphere, and how they might impact the mixing of organics in the atmosphere and on the ground and affect the potential for Titan to harbour basic forms of life.