Space Sunday: moon water and space telescopes

A visualisation of subsurface water ice deposits within PSR – permanently shadowed regions – of the Moon’s south pole, including the craters Cabeus, Shoemaker and Faustini. Credit: NASA Goddard Space Centre

The Moon is a fascinating place; there is no two ways about it. Like many bodies within the solar system, it is proving to be a lot more surprising than we’d previously thought. Up until 2009, for example, it was accepted that the Moon was a dry, arid place with little or no subsurface bodies of water ice. This idea was turned on its head in 2009 after India’s first lunar mission, Chandrayaan I, and NASA’sLunar Reconnaissance Orbiter (LRO) confirmed the presence of water ice within the so-called permanently shadowed regions (PSRs) – deep craters around the lunar poles which never see direct sunlight in their basins.

However, one of the questions surrounding these discoveries is just how much water might actually exist as ice within these shadowed craters? A new study,  published in August 2018, has sought to address this question; it is the work of Shuai Li – a post-doctoral researcher at the University of Hawaii, and  produced with the assistance of researchers from Brown University, the University of Colorado Boulder, the University of California Los Angeles, John Hopkins University, and NASA’s Ames Research Centre.

Li’s study focuses on data returned by NASA’s Moon Minerology Mapper (M³), flown aboard the Chandrayaan I mission. M³ was designed to measure light being reflected from the illuminated regions on the Moon, making its use over the PSRs had been considered of minimal value. Nevertheless, Li believed that what data M³ had gathered on the south polar craters might hep in determining the potential volume of water ice within those craters, as indicated by the Lunar Orbiter Laser Altimeter (LOLA), Lyman-Alpha Mapping Project and Diviner Lunar Radiometer Experiment on the LRO mission. However, what he found came as a complete surprise.

While I was interested to see what I could find in the M3 data from PSRs, I did not have any hope to see ice features when I started this project. I was astounded when I looked closer and found such meaningful spectral features in the measurements … We found that the distribution of ice on the lunar surface is very patchy, which is very different from other planetary bodies such as Mercury and Ceres where the ice is relatively pure and abundant. The spectral features of our detected ice suggest that they were formed by slow condensation from a vapour phase either due to impact or water migration from space.

– Shuai Li, leader of the study team

 

Exposed water ice (green or blue dots) in lunar polar regions and temperature. Credit: Shuai Li

While likely the results of vapour capture following asteroid impacts, Li’s study again opens the door as to how much sub-surface water ice might also exist deeper within the polar regions of the Moon. As I recently noted, a separate study, evidence has been put forward for periods in the Moon’s early history when liquid water existed on the lunar surface at a time when the Moon had a volcanically-induced atmosphere. Much of this water was likely lost to space as that atmosphere dissipated at the end of the Moon’s active volcanic period; however, some of it may have gone underground again, notably in these polar regions.

Either way, the existence of water ice deposits strengthen the case for a return to the Moon and – as NASA Administrator Jim Bridenstine recently indicated – see the establishment of a permanent human presence on the Moon.  An available and plentiful supply of water would go a long way to easing many of the logistical requirements for such a human presence. Once melted, a local supply of water can be filtered and purified to provide drinking water; it can also be used in construction work and as “grey” water for use in growing local foodstuffs through hydroponic or other means; it can be electrolysed to produce oxygen in support of the atmosphere within a base and hydrogen than could be used to power fuel cells, and so on.

The European Space Agency (ESA) in particular is researching ways and means to build a lunar settlement using what is called “in-situ resource utilisation” (ISRU), or the use of locally available materials. In particular ESA has been using locally available “lunar simulants” available here on Earth – notably certain types of volcanic dusts that have been shown to have very similar properties to the dry dust of the surface-covering lunar regolith on the Moon – to test potential options for base construction.

One of these I’ve again previously written about, is the idea of using regolith to effectively “3D print” a protective “shield” of regolith over the facilities of a lunar base to protect it against solar radiation. Referred to as “additive manufacture”, such a technique might be aided with a readily available source of water which can help mix the regolith into a cement-like form that can be “printed” over the structure of a base in layers. In addition, ESA is using a regolith simulant to make “bricks” which can be used to physically construct the walls, floors and ceilings of a base – a process that might again  be easier with a supply of water for use in the process.

A “lunar brick” produced by ESA using “3D printing” techniques and lunar regolith simulants. Credit: ESA

But it is in production of oxygen and hydrogen, as well as offering a source for liquid water, that the ice deposits offer the greatest potential benefit. Up until now, ideas for oxygen production on the Moon have focused on “cracking” the regolith to release the oxygen within it (thought to be around 40% by volume). This requires a lot of energy to achieve –  more than is needed to melt and electrolyse ice to produce both oxygen and hydrogen.

However, it’s not all plain sailing for humans on the Moon. The dust comprising lunar regolith is extremely electro-statically charged, making it stick to just about anything – so keeping it out of a lunar habitat could prove difficult. Worse, it also presents a range of potential health hazards – up to and including major respiratory problems such as lung cancer. These risks have yet to be fully assessed, and countering them as far as possible must be a priority before there can be real talk of a long-term human presence on the Moon.

But in the meantime, Li’s study potentially adds important food for thought for those thinking about establishing research facilities on the Moon.

Continue reading “Space Sunday: moon water and space telescopes”

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Victorian scandals, future oppression, and reflections on life

Seanchai Library

It’s time to highlight another week of storytelling in Voice by the staff and volunteers at the Seanchai Library. As always, all times SLT, and events are held at the Library’s home at Holly Kai Park, unless otherwise indicated.

Sunday, August 26th

13:30: Tea-time at Baker Street

Back from a well-earned break, Sherlock Holmes and John Watson return to their rooms at 221B Baker Street to be joined by Caledonia Skytower, Corwyn Allen and David Abbot and Bryn Taleweaver, as Seanchai Library’s popular Sunday feature resumes.

“This photograph” by Sidney Paget, July 1891 (wikimedia)

This week comes one of Sir Arthur Conan Doyle’s most well-liked mysteries to have engaged his Great Detective, and which first appeared in The Strand Magazine in 1891, before going on to be the first story in the 1982 collection, The Adventures of Sherlock Holmes. It was also the first of Doyle’s detective series to be illustrated by Sidney Paget. I’m of course talking about A Scandal in Bohemia.

In March 1888, Dr. John Watson, married and with his own medical practice is returning home when, on a whim, he drops in at 221B Baker Street to see Holmes. No sooner has Watson arrived, than Holmes demonstrates some of his incredible deductive powers – which are shortly given greater exercise when, after receiving his expected guest, who arrives during the reunion, Holmes pronounces  him to be not “Count Von Kramm” as he purports, but rather Wilhelm Gottsreich Sigismond von Ormstein, Grand Duke of Cassel-Felstein and the hereditary King of Bohemia.

Admitting Holmes has correctly identified him, the king reveals he is seeking Holmes’ assistance in a matter of some delicacy. It revolves around a liaison he had five years’ previously with an American opera singer, Irene Adler, and which could now threaten his upcoming marriage to a Scandinavian princess. Thus Sherlock Holmes comes to pit his wits against an adversary he will forever only refer to as “the Woman” …

18:00: Magicland Storytime: Aladdin and the Magic Lamp

With Caledonia Skytower at the Golden Horseshoe.

Monday, August 27th 19:00: The R-Master

In the 21st century utopia has arrived in the form of a repressive but seemingly benevolent, if omnipresent, bureaucracy. Their perfectly ordered world, seemingly run for the benefit of all, is actually ruled with an iron fist. In claiming to have people’s best interest at heart, those in power keep the population occupied and docile with menial tasks and the promise of advancement with the aid of the strictly controlled drug, R-47.

For the vast majority, R-47 actually does nothing.But for a special few, observed and selected by the ruling Council, it can massively enhance their intellect, elevating them to the status of “R-Masters” allowing them to solve problems, see advancements, and help ensure – wittingly or not – the Council’s control over the world, cosseted and pampered well away from the drudgery of ordinary life.

However, there is a darker side to R-47: just as it can elevate the intellect of some of those chosen to receive it, so to can it reduce them to imbeciles – and there is no way of knowing who the outcome might be in advance. Wally Ho is one selected to receive R-47 – and suffers the latter fate.

Determining it will raise his problem-solving abilities and restore his brother, Etter Ho obtains R-47 and takes it. But, once elevated to the privileged ranks of the R-Masters and witness the truth behind the Council’s rule, Etter determines the established status quo cannot allowed to continue, and Big Brother must be brought to heel.

Join Gyro Muggins as he reads Gordon R. Dickson’s 1973 novel about life in what is now our times!

Tuesday, August 28th 19:00: Calypso

David Sedaris is a Grammy Award-nominated American humorist and radio contributor, known for his collections of essays and short stories which are mostly autobiographical and self-deprecating in content and style.

When he buys a beach house on the Carolina coast – which in tpyical fashion he names “Sea Section” -, Sedaris envisions long, relaxing vacations spent playing board games and lounging in the sun with those he loves most. And indeed, that’s how it appears to start, apart from one annoying little truth he soon discovers. To quote an unrelated film: “no matter where you go, there you are”; which for Sedaris means when all is said and done, you cannot take a vacation from yourself.

This realisation brings Sedaris’ formidable powers of observation and dry humour to the fore as he considers middle age and mortality and the dawning understanding that life has reached a point where perhaps life has reached a point where the best parts of the story are behind you, rather than awaiting your arrival. Dark, yes; a little morbid, possibly, but the humour is unmistakable and so deeply rooted in the unfolding of this personal tale, it’s impossible not to become caught up within it.

Join R. Crap Mariner – the perfect voice to bring life to Sedaris’ words – and hear more.

Wednesday, August 29th 19:00: More Tales of the Arabian Nights

With Caledonia Skytower – check the Seanchai Blog nearer the time for more details.

Thursday, August 30th

14:00: Fireside Tales Eclectic Readings with Meteor Mags

“A Public Presentation of Poetry, Pirates, Pumas, Pussycats, Planets, Ponies, and Prehistoric Pteranodons.”

19:00: Ghost Pirates!

With Shandon Loring. Also presented in Kitelyhop://grid.kitely.com:8002/Seanchai/144/129/29.

 


Please check with the Seanchai Library’s blog for updates and for additions or changes to the week’s schedule.

The current charity is Feed a Smile.