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Engineers for the James Webb Space Telescope are in the midst of an intricate, three-month-long process of aligning the telescope’s 18 separate mirror segments to work together as one giant, high-precision 6.5-meter (21.3-foot) primary telescope mirror.

This process, called phasing, began in early February and includes seven different steps, which goes from taking the mirrors’ initial placements after they were deployed to doing a “coarse” and then “fine” alignment, and then making sure the mirror works with all four of Webb’s instruments and their various fields of view.

As of this week, engineers are just on step number two, an indication of how precise and detailed this procedure is. And while Webb teams have tested and simulated the process countless times here on Earth, they’ve never been able to perform the entire process under all of the in-space conditions the telescope is now experiencing. Engineers can simulate the cold and vacuum of space here on Earth, but they can’t simulate zero G.

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Fully functional, 1/6th scale model of the JWST mirror in optics testbed. Credit: NASA

“We built a testbed telescope, which looks a lot like Webb but is 1/6th the size,” explained Lee Feinberg, the Optical Telescope Element Manager for the mission, in an interview last month, “and we proved we knew how to move the mirrors to align them. Then we tested the full telescope in the vacuum chamber at Johnson Space Center at temperature and pressure. There, we were able to demonstrate aspects of the process, but not the whole thing. So, the first full time we’re doing the entire process is when the telescope is in space.”

On February 12, the telescope team announced the first photons of starlight had traveled through the entire telescope and were detected by the Near Infrared Camera (NIRCam) instrument. NICCam is being used to align the mirrors and calibrate the telescope, and it took 18 out-of-focus images of one star, one picture from each mirror segment.  Now, scientists and engineers have taken these unfocused images and are using them to slowly fine-tune the telescope. The team says that so far, the initial results match expectations and simulations.

“I like to think of it as, that we have 18 mirrors that are right now, little prima donnas, all doing their own thing, singing their own tune in whatever key they’re in,” said Jane Rigby, Webb operations project scientist, during a press briefing earlier this month. “We have to make them work like a chorus, and that is a methodical, laborious process.”

The telescope’s 18 primary mirror segments need to match each other to a fraction of a wavelength of light – approximately 50 nanometers. Each segment has six actuators or tiny mechanical motors attached to the back that can align the segments, along with an additional actuator at the center of each segment that adjusts its curvature.

The first stage in this process, called “Segment Image Identification” had the team move each of Webb’s 18 primary mirror segments to bring 18 unfocused copies of a single star into a planned hexagonal formation. The lead image, above, shows that alignment. The first movements of the mirror segments can be as small as a centimeter or less, the final movements will be tens of nanometers, which is only one-ten thousandth the width of a human hair.

The remaining steps:

2. Segment Alignment: A process called Phase Retrieval uses mathematical analysis to determine the precise positioning errors of the segments. Adjustments of the segments then result in 18 well-corrected “telescopes.” However, at his current stage, the segments still don’t work together as a single mirror.

webb array images
?? In the coming weeks, our team will align & focus each of these 18 dots, then stack the dots on top of each other to form a single point — one unified image from all of Webb’s 18 mirror segments. What’s ahead: https://t
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New Simulation Explains how Supermassive Black Holes Grew so Quickly

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One of the main scientific objectives of next-generation observatories (like the James Webb Space Telescope) has been to observe the first galaxies in the Universe – those that existed at Cosmic Dawn. This period is when the first stars, galaxies, and black holes in our Universe formed, roughly 50 million to 1 billion years after the Big Bang. By examining how these galaxies formed and evolved during the earliest cosmological periods, astronomers will have a complete picture of how the Universe has changed with time.

As addressed in previous articles, the results of Webb‘s most distant observations have turned up a few surprises. In addition to revealing that galaxies formed rapidly in the early Universe, astronomers also noticed these galaxies had particularly massive supermassive black holes (SMBH) at their centers. This was particularly confounding since, according to conventional models, these galaxies and black holes didn’t have enough time to form. In a recent study, a team led by Penn State astronomers has developed a model that could explain how SMBHs grew so quickly in the early Universe.

The research team was led by W. Niel Brandt, the Eberly Family Chair Professor of Astronomy and Astrophysics at Penn State’s Eberly College of Science. Their research is described in two papers presented at the 244th meeting of the American Astronomical Society (AAS224), which took place from June 9th to June 13th in Madison, Wisconsin. Their first paper, “Mapping the Growth of Supermassive Black Holes as a Function of Galaxy Stellar Mass and Redshift,” appeared on March 29th in The Astrophysical Journal, while the second is pending publication. Fan Zou, an Eberly College graduate student, was the lead author of both papers.

Illustration of an active quasar. What role does its dark matter halo play in activating the quasar? Credit: ESO/M. Kornmesser
Illustration of an active quasar. New research shows that SMBHs eat rapidly enough to trigger them. Credit: ESO/M. Kornmesser

As they note in their papers, SMBHs grow through two main channels: by accreting cold gas from their host galaxy or merging with the SMBHs of other galaxies. When it comes to accretion, previous research has shown that a black hole’s accretion rate (BHAR) is strongly linked to its galaxy’s stellar mass and the redshift of its general stellar population. “Supermassive black holes in galaxy centers have millions-to-billions of times the mass of the Sun,” explained Zhou in a recent NASA press release. How do they become such monsters? This is a question that astronomers have been studying for decades, but it has been difficult to track all the ways black holes can grow reliably.”

For their research, the team relied on forefront X-ray sky survey data obtained by NASA’s Chandra X-ray Observatory, the ESA’s X-ray Multi-Mirror Mission-Newton (XMM-Newton), and the Max Planck Institute for Extraterrestrial Physics’ eROSITA telescope. They measured the accretion-driven growth in a sample of 8000 active galactic nuclei (AGNs) located in 1.3 million galaxies. This was combined with IllustrisTNG, a suite of state-of-the-art cosmological simulations that model galaxy formation, evolution, and mergers from Cosmic Dawn to the present. This combined approach has provided the best modeling to date of SMBH growth over the past 12 billion years. Said Brandt:

“During the process of consuming gas from their hosting galaxies, black holes radiate strong X-rays, and this is the key to tracking their growth by accretion. We measured the accretion-driven growth using X-ray sky survey data accumulated over more than 20 years from three of the most powerful X-ray facilities ever launched into space.

“In our hybrid approach, we combine the observed growth by accretion with the simulated growth through mergers to reproduce the growth history of supermassive black holes. With this new approach, we believe we have produced the most realistic picture of the growth of supermassive black holes up to the present day.”

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This still image shows the timeline running from the Big
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10 Tips for Taking Kids on Their First Backpacking Trip

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By Michael Lanza

Whether you’re a family of novices planning your first backpacking trip or an experienced backpacker ready to take your kids on their first multi-day hike, heed this friendly advice: You’re in for some surprises. And I speak from experience. I’d been backpacking for years—in fact, I was already working as a professional backpacker—when my wife (also a longtime backpacker) and I first dove into the grand new adventure of taking our young kids into the wilderness.

We learned a lot. But the biggest lesson was this: Our backcountry adventures brought us closer together as a family and helped mold our children into eager and skilled backpackers and confident young adults with a passion and appreciation for the outdoors—and who seize every chance to spend time with us (their parents!) outdoors (and indoors!).

This article shares lessons I learned while taking our kids on countless backpacking trips since they were quite little and over the course of the 10 years I spent as Northwest Editor of Backpacker magazine and even longer running this blog.

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Hi, I’m Michael Lanza, creator of The Big Outside. Click here to sign up for my FREE email newsletter. Join The Big Outside to get full access to all of my blog’s stories. Click here for my e-books to classic backpacking trips. Click here to learn how I can help you plan your next trip.

A young girl backpacking the High Sierra Trail above Hamilton Lakes, Sequoia National Park.
” data-image-caption=”My daughter, Alex, backpacking the High Sierra Trail above Hamilton Lakes, Sequoia National Park, which is also the lead photo at the top of this story.
” data-medium-file=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2.jpg?fit=300%2C199&ssl=1″ data-large-file=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2.jpg?fit=900%2C598&ssl=1″ src=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2-1024×680.jpg?resize=900%2C598&ssl=1″ alt=”A young girl backpacking the High Sierra Trail above Hamilton Lakes, Sequoia National Park.” class=”wp-image-45459″ srcset=”https://tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2.jpg 1024w, https://tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2.jpg 300w, https://tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2.jpg 768w, https://tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2.jpg 150w, https://tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2020/05/06230302/Sierra3-040-High-Sierra-Trail-above-Hamilton-Lakes-Sequoia-N.P.-CA-2.jpg 1200w” sizes=”(max-width: 900px) 100vw, 900px” data-recalc-dims=”1″ />My daughter, Alex, backpacking the High Sierra Trail above Hamilton Lakes, Sequoia National Park.

Follow the tips below to make your family backpacking trips a success and ensure that your kids want to go again and again. Like many stories at The Big Outside, much of this one is free for anyone to read but reading the entire story requires a paid subscription. If you’re already a subscriber, thank you for supporting my blog.

Please share your thoughts, questions, or your own tips in the comments section at the bottom of this story. I try to
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A Survival Guide For the Outdoors Lover Who’s a New Parent

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By Michael Lanza

So, you’ve been an avid [circle all appropriate terms: hiker/backpacker/climber/trail runner/skier/kayaker] for years, and now you’re spending big chunks of your days changing diapers and your nights wondering when you’ll sleep again. You’ve never gone this long without getting out into the mountains, and you see no remedy for that shortfall in the foreseeable future. Your new baby is more wonderful than you’d ever imagined—and yet, you’re feeling a little despair over what’s missing from your life lately.

I know where your head is right now. And I have good news for you: I’ve reached the bright light at the end of the tunnel, and you can get there faster than you might think. Here’s how.

A family on a hike in Idaho’s City of Rocks National Reserve.
” data-image-caption=”My family on a hike in Idaho’s City of Rocks National Reserve. Click photo to read my “10 Tips for Raising Outdoors-Loving Kids.”
” data-medium-file=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2017/06/06235050/Us-4-at-COR-June04.jpg?fit=244%2C300&ssl=1″ data-large-file=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2017/06/06235050/Us-4-at-COR-June04.jpg?fit=521%2C640&ssl=1″ src=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2017/06/06235050/Us-4-at-COR-June04.jpg?resize=521%2C640&ssl=1″ alt=”My family on a hike in Idaho’s City of Rocks National Reserve.” class=”wp-image-23944″ srcset=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2017/06/06235050/Us-4-at-COR-June04.jpg?resize=521%2C640&ssl=1 521w, https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2017/06/06235050/Us-4-at-COR-June04.jpg?resize=521%2C640&ssl=1 244w, https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2017/06/06235050/Us-4-at-COR-June04.jpg?resize=521%2C640&ssl=1 200w” sizes=”(max-width: 521px) 100vw, 521px” data-recalc-dims=”1″ />My family on a hike in Idaho’s City of Rocks National Reserve.

First of all, I know it’s hard to take a long view when you’re so deeply buried in the day-to-day management of a hectic life. But as a father of two young adults, I can tell you that growing children race through development stages—each one very different—with blinding speed. While in many respects the infant and toddler years are the most demanding (and cutest), and can seem eternal at times, they do pass. In my experience, parenting keeps getting better.

But for now, you need some strategies for surviving the early years of parenting, when you face the greatest demands on your personal time—and your sanity.

The following tips reflect what I’ve learned from more than 20 years as a parent who has always strived to get outside as much as possible—dayhiking, backpacking, climbing, running, paddling, skiing—with my family whenever I can, but also, at times without them.

Please share your questions or tips in the comments section at the bottom of this story. I try to respond to all comments. Click on any photo to read about that trip.

Tet19 047 Me on Teton Crest Trail copy cropped 31
Hi, I’m Michael Lanza, creator of The Big Outside. Click here to sign up for my FREE email newsletter. Join The Big Outside to get full access to all of my blog’s stories. Click here for my e-books to classic backpacking trips. Click here to learn how I can help you plan your next trip.

A baby girl in Skillern Hot Springs, Smoky Mountains, Idaho.
” data-image-caption=”My daughter, Alex, at Skillern Hot Springs, Smoky Mountains, Idaho. Click photo to read my “10 Tips for Raising Outdoors-Loving Kids.”
” data-medium-file=”https://i0.wp.com/tbo-media.sfo2.digitaloceanspaces.com/wp-content/uploads/2014/05/07010457/Alex-at-Skillern-Hot-Springs-Smoky-Mtns-ID-2.jpg
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