RocketDoc Notes for January 9, 2022 - James Webb Telescope Summary

JWST Deployment News


Deployment of the JWST is carefully planned and has been proceeding close to schedule. The overall plan is shown in figure 1 below.


Figure 1 – JWST Deployment Timeline


Launch + 5.5 days - Now a half-million miles and six days outbound from Earth, the James Webb Space Telescope began the most critical phase of its initial activation on Friday, unfolding a fragile five-layer sunshield the size of a tennis court that's essential to its mission.

The two pallets holding the sunshade's hair-thin Kapton layers were unfolded and locked in place Tuesday, one on either side of Webb's 21.3-foot primary mirror. On Thursday, protective covers were commanded to roll off each pallet, exposing the still-folded sunshade membranes to space. The actual deployment began December 31st when the first of two telescoping booms at right angles to the pallets began extending, slowly pulling out one side of the shield, unfolding the membranes as it went. The boom was verified to be fully extended at 4:49 p.m. EST

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The deployment of the first boom was held up several hours to give engineers time to make sure the protective covers had, in fact, rolled off to the side of the sunshade pallets as required. “Switches that should have indicated that the cover rolled up did not trigger when they were supposed to," NASA said in a blog post. "However, secondary and tertiary sources offered confirmation that it had."


"The deployment of the five telescoping segments of the motor-driven mid-boom began around 1:30 p.m., and the arm extended smoothly until it reached full deployment," NASA said. Engineers then sent commands to deploy the second sunshade boom, which extended smoothly and locked in place at 10:13 p.m., finally giving Webb its iconic kite-like shape.

"Today is an example of why we continue to say that we don't think our deployment schedule might change, but that we expect it to change," said Keith Parrish, the observatory manager at NASA's Goddard Space Flight Center.


Today – Launch + 12 – The latest news from NASA says they have successfully deployed the secondary mirror and the aft instrument radiator and tomorrow they will deploy the Port Primary Mirror Wing. See figure 2 below.


Figure 2 – Port Primary Mirror during deployment


As you can see from Figure 1 they are shuffling the deployment sequence because of spacecraft temperature and power limits but they slightly ahead of schedule. Once the two wings are deployed, they can focus on alignment and checking out the optics. 30 days after launch they will be at L2, and after another 5 months of checkout ready to explore the universe.


What does JWST buy us?


Much has been made of the $10 B price tag for JWST but what do we acquire if it works as advertised? The enclosed article does a good job describing what JWST offers.


Authored by Hillary Davis

Friday, Dec. 31, 2021 | 2 a.m.

When the James Webb Space Telescope gets into place next month about a million miles from Earth, it will allow scientists to see the light of distant galaxies and marvel at the origins of the universe.


UNLV astrophysicist Jason Steffen will do both plus study the data the telescope sends back on the atmospheres of exoplanets, or planets that orbit other stars. Exoplanet study is another key part of the Webb mission and is Steffen’s specialty.


Since 2008 he’s been a member of the science team for NASA’s Kepler Space Telescope mission that searched for exoplanets in the Milky Way.


And he says studying those distant stars is downright fascinating.

“Being able to detect things like water, carbon dioxide, some complex molecules in the atmosphere, is going to be a pretty big deal,” said Steffen, a physics professor.

The James Webb Space Telescope, named for one of NASA’s first administrators, is a joint effort of NASA, the European Space Agency and the Canadian Space Agency. It will look relatively near, in our own solar system, and far back into space and time, capturing the light from the first galaxies in the early universe.


For NASA, Steffen works primarily with Kepler data. The Kepler telescope, set in deep space, measured the brightness variation of stars, capturing what could be orbiting planets passing through their glow. Using these Kepler observations, he been part of many recent discoveries in exoplanet science — like the possibility that closely neighboring planets in the same solar system could share life.


Steffen said the Webb telescope’s Christmas day launch from French Guiana, on the northern coast of South America, went well and the telescope was transiting as expected. It should set up around Jan. 24 at a point called L2, one of five points within the Earth’s orbit where the gravitational forces of the sun and Earth can hold an object in place. Think of this as the telescope’s parking space.


He says the telescope launch carries great significance. Here’s why:


Infrared

Webb sees in the infrared region of the electromagnetic spectrum.


Electromagnetic energy travels in waves. Radio waves are long. Gamma rays are short. The human eye can only detect “visible light,” a small portion of the spectrum.

Infrared has longer wavelengths than visible light, so we can’t see it. Webb’s camera can.

People may be familiar with the Hubble Space Telescope, which launched in 1990 and is still in operation, snapping stunning, sharp images of stars, planets and galaxies in various life stages. Hubble’s camera sees primarily in visible light, though. Objects look opaque when viewed through this visible light instrument because they are obscured by dust.


“When you’re looking at a star-forming region, you’re going to have columns of cold material with a lot of dust in it,” Steffen said. “In order to see what’s going on in there, you have to look at long wavelengths so that the light can leave from the objects you study and make it through that cloud. It’s a way to look through clouds, basically, for planet formation and star formation.”

Also, when studying the furthest-away galaxies in the expanding universe, the light from the developing galaxies is lengthened — stretched out — from visible light into the infrared. This requires an infrared instrument.


Earth’s greenhouse gases — like water, carbon dioxide and methane — block infrared waves in either direction. So, Webb has to get above Earth’s atmosphere to fix its more penetrating “gaze.”


Though Webb will be bigger and more sensitive, it will be complementary to Hubble, Steffen said.

I would like to emphasize the importance of operating in the infrared spectrum. Especially when looking back to within 300 million years of the Big Bang. Understanding what happened right after the Big Bang could solve many riddles like the origin of Dark Matter and what happened to all the anti-matter? It’s too early to declare the JWST a success but so far everything is going according to plan.


Thinking big

But why would most people, who aren’t astronomers or planetary scientists, want people to study space?


Astronomy creates awe-inspiring images, which hook people and get them to pursue other sciences with practical applications here on Earth, like building bridges, Steffen said.

It also explains the physical nature of how the universe and Earth formed. It investigates how stars and other planets form. With this knowledge, people can compare other bodies to our own planet and sun. Those are pretty big existential notions too.

“The James Webb Space Telescope represents the ambition that NASA and our partners maintain to propel us forward into the future,” NASA Administrator Bill Nelson said in a statement. “The promise of Webb is not what we know we will discover; it’s what we don’t yet understand or can’t yet fathom about our universe.”


Want to follow Webb’s progress? Visit www.jwst.nasa.gov/ for more.


Media Position on James Webb Space Telescope (JWST)


Nasa’s Webb telescope is a joy. But it’s the private ventures that push at limits – Article by Martin Rees for The Guardian Newspaper.

Martin and I agree only on some parts of this article.


Working Hypothesis -Spacefaring adventurers, living and experimenting with new technology, could potentially spawn a post-human era.


Figure 3 - An artist’s impression of the James Webb Space Telescope (JWST), which was launched on board an Ariane 5 rocket on Christmas Day. Photograph: ESA/D.DUCROS

Sun 2 Jan 2022 04.00 EST


After years of delay, and massive cost over-runs, the James Webb space telescope (the JWST) was launched on Christmas Day. It will need to perform complex automated operations now it’s in space.


The first and most challenging is happening this week: unfurling a heat shield the size of a tennis court. After this, its 6.5-metre mirror must be assembled from 18 pieces packed within the launching rocket’s nose cone. There’s much that can go wrong, and astronomers will remain anxious for the several months that will elapse before all necessary deployments and tests are completed.


After the Hubble Space Telescope was launched more than 30 years ago, its mirror turned out to be mis-ground. But astronauts undertook a “rescue” mission to add corrective optics and later made further visits to upgrade the instruments.


The stakes are higher for the JWST: it’s vastly more complex, but there is no prospect of a repair mission. The Hubble telescope was in a low (and accessible) orbit: in contrast, the JWST’s orbit will be several times further away than the moon – far beyond the reach of astronauts without a major transportation upgrade. Some might argue that we therefore need to instigate more ambitious plans for human spaceflight: to enable human assembly of large structures in deep space, to return to the moon, and eventually to reach Mars. But I don’t share this view. Indeed, as robotics and miniaturization improve, the practical and scientific case for human spaceflight weakens. Its prime motive now is simply as an adventure – an ultra-expensive sport that should be left to billionaires and private sponsorship. I disagree with the premise that further space exploration should be virtual. Humans are essential to solving many extraterrestrial problems and well worth the expense of including them to certain venues like the moon and Mars. But we don’t want humans to explore difficult regions like the surface of Venus or the clouds of Jupiter.


Space technology has burgeoned – for communication, environmental monitoring, satnav and so forth. We depend on it every day. Unmanned probes to other planets have beamed back pictures of varied and distinctive worlds. And telescopes in space have revolutionized our knowledge of the cosmos.


During this century, the whole solar system will be explored by flotillas of miniaturized probes, far more advanced than, for instance, Nasa’s wonderful Cassini probe, which spent 13 years exploring Saturn and its moons. This was launched 20 years ago and based on 1990s technology. Think how much better we could do today. Robotic fabricators will assemble vast lightweight structures in space (huge, gossamer-thin mirrors or solar energy collectors, for instance), maybe using raw materials mined from the moon or asteroids. And they could repair spacecraft in orbit far beyond the moon. Robotic and AI techniques are evolving fast. For instance, the Curiosity vehicle sent to Mars a decade ago trundled slowly across a Martian crater; if it encountered a rock, it needed instructions from Earth about how to divert its path. In contrast, Perseverance, which landed on Mars last February, has sufficient intelligence to find its way around obstacles. In another decade, such a probe will have AI sufficient to identify and explore interesting sites and geological formations.


Nasa’s program for human spaceflight, ever since Apollo, has been impeded by public and political pressure into being exceedingly risk averse. The space shuttle failed twice in 135 launches. Thrill-seekers would willingly accept this 2% level of risk. But the shuttle had, unwisely, been promoted as “safe”. So each failure caused a national trauma and was followed by a hiatus while costly efforts were made (with very limited effect) to reduce the risk. Because of this safety culture, Nasa will confront political obstacles in achieving any grand goal within a feasible budget. I concur with his opinion here.


It’s a dangerous delusion to think that space offers an escape from Earth’s problems. We’ve got to solve them here. I have published numerous papers showing that off-world resources will speed up solving our major problem – global warming.



But private enterprise ventures – SpaceX, Blue Origin and the rest – bringing a Silicon Valley culture into a domain long dominated by the NASA and a few aerospace conglomerates, can cut costs and tolerate higher risks than a western government could impose on publicly funded civilian astronauts. So, it’s these ventures, with private funds and sponsorship, which should front manned missions. The phrase “space tourism” should be avoided. It lulls people into believing such ventures are routine and low risk. And if that’s the perception, the inevitable accidents will be as traumatic as those of the space shuttle. These exploits must be sold as dangerous sports or intrepid exploration. He is missing one major point about the private enterprise space ventures. Not only they are risk takers, but they are smart and innovative. They acquired all the best technologies from NASA and the aerospace conglomerates and then applied advanced design and build techniques from Silicon Valley to reduce time to build and development costs by about a factor of five relative to NASA projects. This allows the low costs to orbit needed for human expansion into space.


Don’t ever expect mass emigration from Earth. And here I disagree strongly with Elon Musk and with my late colleague Stephen Hawking. It’s a dangerous delusion to think that space offers an escape from its problems. We’ve got to solve them here. Coping with climate change is a doddle compared to terraforming Mars. Nowhere in our solar system offers an environment even as clement as the Antarctic or the top of Everest. There’s no “Planet B” for ordinary, risk-averse people. Nonetheless, this century courageous thrill-seekers may establish bases independent from the Earth. Musk himself says he wants to die on Mars – but not on impact. Although we may not want to join these space adventurers, we should cheer them on. This is why. They’ll be ill-adapted to Martian conditions, so they’ll have a compelling incentive to redesign themselves. They’ll harness the super-powerful genetic and cyborg technologies that will be developed. These techniques will, one hopes, be restrained on Earth, on prudential and ethical grounds, but settlers on Mars will be beyond the clutches of the regulators. We should wish them good luck in modifying their progeny to adapt to alien environments. This might be the first step towards divergence into a new species. I have no idea where this came from? There is no effort anywhere in the U.S. public or private space industry looking at changing humans for living on Mars. I think the Mr. Rees has been reading too much Science Fiction. On the other hand, there has been progress on understanding what is going to take infrastructure-wise to live on Mars. It is achievable with Musk’s Starship, but it’s not going to be cheap.


So, it’s these spacefaring adventurers, not those of us comfortably adapted to life on Earth, who will spearhead the post-human era, evolving within a few centuries into a new species. (This evolution, proceeding on the timescale of technological advance, is potentially thousands of times faster than Darwinian selection.) No idea where this conclusion is coming from?


Moreover, if they make the transition from flesh and blood to fully inorganic intelligences, they won’t need an atmosphere. And they may prefer zero-g, especially for constructing massive artifacts. So, it’s in deep space – not on Earth, nor even on Mars – those non-biological “brains” may develop powers that humans can’t even imagine.


The sun will survive 6 billion more years before its fuel runs out. And the expanding universe will continue far longer, perhaps forever. So even if intelligent life had originated only on the Earth, it need not remain a trivial feature of the cosmos: it could jump-start a diaspora whereby ever more complex intelligence spreads through the whole galaxy, via self-reproducing machines, transmitting DNA, instructions for 3D printers or suchlike. Interstellar voyages would hold no terrors for near immortals. There’s plenty of time ahead. This assumes we can achieve true artificial intelligence and humans can transfer their intelligence to a computerized brain. That was predicted many years ago and progress has been rather slow lately. I give it maybe a 50-50 chance in the next fifty years.

Note: Martin Rees is astronomer royal


Thanks for Reading and Stay Safe,

Dana Andrews

retiredrocketdoc.com



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