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After mission failure, Boeing spacecraft lands in New Mexico – Daily Times

Published

2 years ago

December 25, 2019

Harry Miller

Boeing’s new Starliner unmanned spacecraft returned to Earth on Sunday, landing in the New Mexico desert in the United States six days early after a clock problem prevented a rendezvous with the International Space Station.

Images broadcast by NASA showed the spacecraft touching down safely in the dark after a descent slowed by three large parachutes.

The Starliner capsule was launched Friday from Cape Canaveral in Florida, but shortly after separating from its Atlas V launch rocket, its thrusters failed to activate as planned, preventing it from reaching an orbit high enough to meet up with the ISS.

The space station orbits at an altitude of about 400 kilometers (250 miles) above sea level. Notably, the flight, carrying only a dummy, was meant to be a final dress rehearsal before a crewed flight.

After calculating that the craft had burned too much propellant for several minutes, Boeing and NASA were forced to guide the Starliner back to Earth without fulfilling its planned mission.

Starliner was able to establish a communications link with the ISS, and to test in space its docking mechanism as well as its solar panels, batteries, thrusters and heat regulation system.

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India among 11 ‘countries of concern’ on climate change for U.S. spy agencies

Published

3 hours ago

October 21, 2021

Sonia Ulebor

Afghanistan, India and Pakistan were among 11 countries singled out by U.S. intelligence agencies on Thursday as being “highly vulnerable” in terms of their ability to prepare for and respond to environmental and societal crises caused by climate change.

In a new National Intelligence Estimate, the Office of the Director of National Intelligence (ODNI) predicts that global warming will increase geopolitical tensions and risks to U.S. national security in the period up to 2040.

Such estimates are broad U.S. intelligence community assessments. Thursday’s report identifies as particular “countries of concern” Afghanistan, India, Pakistan, Myanmar, Iraq, North Korea, Guatemala, Haiti, Honduras, Nicaragua and Colombia. ODNI posted a declassified version online.

Heat, drought, water availability and ineffective government make Afghanistan specifically worrying. Water disputes are also a key geopolitical flashpoint in India and the rest of South Asia.

The report identifies two additional regions of concern to U.S. intelligence agencies. Climate change is “likely to increase the risk of instability in countries in Central Africa and small island states in the Pacific, which clustered together form two of the most vulnerable areas in the world.”

The report notes disparities around global approaches to tackling climate change, saying countries that rely on fossil fuel exports to support their economies “will continue to resist a quick transition to a zero-carbon world because they fear the economic, political, and geopolitical costs of doing so.”

The report also notes the likelihood of increasing strategic competition over the Arctic. It says that Arctic and non-Arctic states “almost certainly will increase their competitive activities as the region becomes more accessible because of warming temperatures and reduced ice.”

It predicts international competition in the Arctic “will be largely economic but the risk of miscalculation will increase modestly by 2040 as commercial and military activity grows and opportunities are more contested.”

(Reporting by Mark Hosenball; Editing by Frances Kerry)

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Mining the moon's water will require a massive infrastructure investment, but should we? – Yahoo News Canada

Published

6 hours ago

October 21, 2021

Harry Miller

Building a moon base will require extensive resources and infrastructure. (Shutterstock)

We live in a world in which momentous decisions are made by people often without forethought. But some things are predictable, including that if you continually consume a finite resource without recycling, it will eventually run out.

Yet, as we set our sights on embarking back to the moon, we will be bringing with us all our bad habits, including our urge for unrestrained consumption.

Since the 1994 discovery of water ice on the moon by the Clementine spacecraft, excitement has reigned at the prospect of a return to the moon. This followed two decades of the doldrums after the end of Apollo, a malaise that was symptomatic of an underlying lack of incentive to return.

That water changed everything. The water ice deposits are located at the poles of the moon hidden in the depths of craters that are forever devoid of sunlight.

Since then, not least due to the International Space Station, we have developed advanced techniques that allow us to recycle water and oxygen with high efficiency. This makes the value of supplying local water for human consumption more tenuous, but if the human population on the Moon grows so will demand. So, what to do with the water on the moon?

There are two commonly proposed answers: energy storage using fuel cells and fuel and oxidizer for propulsion. The first is easily dispensed with: fuel cells recycle their hydrogen and oxygen through electrolysis when they are recharged, with very little leakage.

Energy and fuel

The second — currently the primary raison d’être for mining water on the moon — is more complex but no more compelling. It is worth noting that SpaceX uses a methane/oxygen mix in its rockets, so they would not require the hydrogen propellant.

So, what is being proposed is to mine a precious and finite resource and burn it, just like we have been doing with petroleum and natural gas on Earth. The technology for mining and using resources in space has a technical name: in-situ resource utilization.

And while oxygen is not scarce on the moon (around 40 per cent of the moon’s minerals comprise oxygen), hydrogen most certainly is.

Extracting water from the moon

Hydrogen is highly useful as a reductant as well as a fuel. The moon is a vast repository of oxygen within its minerals but it requires hydrogen or other reductant to be freed.

For instance, ilmenite is an oxide of iron and titanium and is a common mineral on the moon. Heating it to around 1,000 C with hydrogen reduces it to water, iron metal (from which an iron-based technology can be leveraged) and titanium oxide. The water may be electrolyzed into hydrogen — which is recycled — and oxygen; the latter effectively liberated from the ilmenite. By burning hydrogen extracted from water, we are compromising the prospects for future generations: this is the crux of sustainability.

But there are other, more pragmatic issues that emerge. How do we access these water ice resources buried near the lunar surface? They are located in terrain that is hostile in every sense of the word, in deep craters hidden from sunlight — no solar power is available — at temperatures of around 40 Kelvin, or -233 C. At such cryogenic temperatures, we have no experience in conducting extensive mining operations.

Peaks of eternal light are mountain peaks located in the region of the south pole that are exposed to near-constant sunlight. One proposal from NASA’s Jet Propulsion Lab envisages beaming sunlight from giant reflectors located at these peaks into craters.

Black and white image of the moon's surface — Black and white image of the moon’s surface

These giant mirrors must be transported from Earth, landed onto these peaks and installed and controlled remotely to illuminate the deep craters. Then robotic mining vehicles can venture into the now-illuminated deep craters to recover the water ice using the reflected solar energy.

Water ice may be sublimed into vapour for recovery by direct thermal or microwave heating – because of its high heat capacity, this will consume a lot of energy, which must be supplied by the mirrors. Alternatively, it may be physically dug out and subsequently melted at barely more modest temperatures.

Using the water

After recovering the water, it needs to be electrolyzed into hydrogen and oxygen. To store them, they should be liquefied for minimum storage tank volume.

Although oxygen can be liquefied easily, hydrogen liquefies at 30 Kelvin (-243 C) at a minimum of 15 bar pressure. This requires extra energy to liquefy hydrogen and maintain it as liquid without boil-off. This cryogenically cooled hydrogen and oxygen (LH2/LOX) must be transported to its location of use while maintaining its low temperature.

So, now we have our propellant stocks for launching stuff from the moon.

This will require a launchpad, which may be located at the moon’s equator for maximum flexibility of launching into any orbital inclination as a polar launch site will be limited to polar launches — to the planned Lunar Gateway only. A lunar launchpad will require extensive infrastructure development.

In summary, the apparent ease of extracting water ice from the lunar poles belies a complex infrastructure required to achieve it. The costs of infrastructure installation will negate the cost savings rationale for in-situ resource utilization.

Alternatives to extraction

There are more preferable options. Hydrogen reduction of ilmenite to yield iron metal, rutile and oxygen provides most of the advantages of exploiting water. Oxygen constitutes the lion’s share of the LH2/LOX mixture. It involves no great infrastructure: thermal power may be generated by modest-sized solar concentrators integrated into the processing units. Each unit can be deployed where it is required – there is no need for long traverses between sites of supply and demand.

Hence, we can achieve almost the same function through a different, more readily achievable route to in-situ resource utilization that is also sustainable by mining abundant ilmenite and other lunar minerals.

Let us not keep repeating the same unsustainable mistakes we have made on Earth — we have a chance to get it right as we spread into the solar system.

This article is republished from The Conversation, a nonprofit news site dedicated to sharing ideas from academic experts. It was written by: Alex Ellery, Carleton University.

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Alex Ellery does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

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Vikings Settled In North America As Early As 1021, Researchers Say – iHeartRadio

Published

7 hours ago

October 21, 2021

Harry Miller

New research has dated Viking ruins in Canada’s Newfoundland to 1021. While archeologists have known that Vikings had settled in North America hundreds of years before European explorers ventured across the Atlantic Ocean and reached the shores of North America, they had never been able to pinpoint exactly when they arrived.

A new study published in Nature provides evidence that around 100 men and women settled at L’Anse aux Meadows in Newfoundland 1,000 years ago.

“This is the first time the date has been scientifically established,” said archaeologist Margot Kuitems, a researcher at the University of Groningen in the Netherlands and the study’s lead author.

“Previously, the date was based only on sagas — oral histories that were only written down in the 13th century, at least 200 years after the events they described took place,” she said.

In order to build their new settlement and repair their ships, the Vikings had to cut down trees in the area. The researchers noted that a burst of cosmic radiation, possibly from a solar storm, hit the Earth in the year 993. Evidence of the storm can be found in tree rings, and researchers used that as a starting date to count the rings on the felled trees. After examining three different pieces of wood, they determined all three were cut down in 1021 using metal tools.

Researchers believe that the Vikings only stayed there for between three and 13 years before they returned to Greenland. The study authors are planning to continue their work and determine exactly how long the Vikings were at L’Anse aux Meadows.

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