Transcript

4.16.26 · Science Show KY

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Speaker 1: Welcome to Radioized Diary of Science and Nature. Your reader's
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Kelly Taylor. I'll have articles on science and nature, but
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first a reminder that RADIOI is a reading service intended
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for people who are blind or have other disabilities and
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make it difficult to read printed material. From Scientific American,
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we start with an article that is headlined. After all
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these years, the Hubble Space Telescope is still awesome. On
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April twenty fourth, nineteen ninety, humanity launched a scientific revolution.
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I mean launched literally. On that day, the Space Shuttle
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Discovery roared into the sky with the Hubble Space Telescope
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nestled in its cargo bay. The telescope is on a
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mission destined to forever change our view of the universe.
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Hubble wasn't the largest telescope ever. It's two point four
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meter mirror is actually considered small these days, but being
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above the atmosphere gave its superpowers. Our air boils and royals,
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blurring the views from ground based instruments. It glows too dimly,
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but enough to limit how faint an object astronomers can see,
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and our air absorbs most ultraviolet and infrared light. Interesting wavelengths.
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Cosmically speaking, getting up, up, and away from all that
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atmosphere made Hubble one of the most important telescopes ever built.
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It revolutionized astronomy. Hubbles saw objects fainter than had ever
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been observed before the telescope, homed in on the speed
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of universe expansion, watched weather changes on the outer planets,
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and proved that every big galaxy has a supermassive black
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hole at its heart. Just to name three amazing feats
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off the top of my head. The major breakthroughs and
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discoveries that came out of this magnificent satellite are so numerous,
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really that even listing them here would be excessive and
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a bit tedious, if incredible astronomical exploration could ever be tedious. Yet,
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despite these successes, I see a lot of chatter online
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and even in the news, somewhat cavalierly dismissing Hubble, saying
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NASA's James Webb Space Telescope, the JWST for short, is
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Hubble's replacement. That's not just unfair, it's wrong. JWST was
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never intended to supplant the Hubble telescope, and in fact
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it can't, given that it was designed for very different observations.
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Hubble is optimized to observe the universe invisible light, the
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kind of light we see with our eyes. It can
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also detect some wavelengths in the ultraviolet and ultraviolet infrared ranges,
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but Hubble can't see most of those parts of the spectrum.
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JWST detects infrared light at much longer wavelengths where different
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astrophysical processes dominate. JWST is a much larger telescope. True,
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it has a six and a half meter wide mirror,
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so it collects about seven times as much light as
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of them. In general, a bigger mirror also means higher
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resolution or a better ability to see find details, yet
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that also depends on the wavelength observed, and in fact,
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at their respective best, Hubble beats out JWST by a smidgeon,
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but that's not really the point. Both are exceptional telescopes
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that are at the forefront of the types of observations
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each can do. Understanding Hubble's power invisible light serves to
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underscore one key field where JWST's infrared vision exceeds it.
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Glimpsing the universe's first galaxies. Hubble's deepest observations showed us
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that there was an unexpected richness of galaxies in the
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distant universe, but the telescope has a limit. The more
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distant a galaxy is, the more red shifted its light becomes.
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As cosmic expansion sweeps the galaxy farther away from us.
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At some point, the bulk of the galaxy's light is
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emitted in infrared, where Hubble cannot see it, but where
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jwst is able to see keenly. That is why the
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newer observatory has been so prolific in breaking distance records
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and giving us unprecedented views into the early universe. There
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is an irony here. The idea for a space telescope
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was first proposed by astronomer Lyman Spitzer in nineteen forty six,
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and in the nineteen sixties astronomer Nancy Grace Roman began
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advocating for nastab one. She later became known as the
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mother of Hubble, and a space telescope planned for launch
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this year is named after her. Delays and budget overruns
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plagued the Bubble project, however, and in the end it
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wound up costing more than ten billion dollars in launching
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much later than originally planned. The same thing happened with JWST.
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Initially proposed to cost less than a billion dollars and
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launched by two thousand and four, its final cost was
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about ten billion, and it didn't go up until twenty
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twenty one. In this way, both telescopes have a similar
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history from a different point of view, though their history
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is extremely different. Hubble launched with a flawed mirror one
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just a micron or two flat at the edges, far
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less than the thickness of a human hair, but more
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than enough to ruinously blur the telescope's vision. I remember
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those fuzzy years well during my PhD research, which I
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spent quite a bit of time working with software that
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mathematically corrected some of Hubbles out of focus images. Thankfully,
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this problem was bypassed with the launch of corrective optics
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in nineteen ninety three, and later instruments had built in
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corrections to make sure observations were focused. Few people today
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seem to even know about that difficult time. There were
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congressional hearings looking into NASA's mistake, and many now focus
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only on Hubble's success. And that's fine, I suppose, as
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long as the lessons learned prevent similar screw ups in
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subsequent space telescopes. In JWST's case, they mostly did. That
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ten billion dollar figure I gave is only halfwrite when
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the costs of that telescope are compared with Hubbles in
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inflation adjusted dollars, especially if you factor in the cost
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of Hubble servicing missions, the much larger JWST is actually cheaper,
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despite its delays and technical woes, And of course, all
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that money bought a telescope that performed nearly flawlessly from
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the start. JWST's primary mission was planned to go on
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for more than five years, a time it will reach
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in twenty twenty seven, but its expected lifetime is at
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least twenty years thanks to careful management of its onboard
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supply of fuel. Note that Hubble's primary mission was meant
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to last only fifteen to twenty years, and it's now
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in its thirty sixth year in space. It's made more
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than one point seven million observations since launch, so Hubble
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is hardly obsolete in terms of cameras, instruments, and even
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its solar panels. It's much better now than when it launched. Admittedly,
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its aging gyroscopes necessary to keep the observatory pointed accurately,
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have had numerous mission plaguing failures, but engineers on the
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ground have found ways to squeeze every last drop of
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efficiency from Hubble's soul operating gyro, NASA has a habit
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of making it its missions last much longer than their
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nominal lifetime. The Chandra X ray Observatory is in its
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twenty sixth year of its five year mission, the Spitzer
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Space Telescope lasted for eleven years past its use by date,
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and the Fermi Gamma Ray Space Telescope is still operating
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after twice its original mission time. If JWST lasts as
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long as Hubble, I'll be happy to see it still
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peering at the infrared sky in twenty fifty seven. Hubble
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may be long gone by then, but we hope we'll
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have other grand observatories in space, not so much replacing
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it as carrying on its legacy. And now from Scientific American,
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we have an article headline to meet the fluffy, funky
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and fabulous native bees that call the US home. This
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is by Megan Barteles has arrived in the US, bringing
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its bright spectacle of budding trees and migrating birds, along
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with more subtle but equally important changes among them the
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annual emergence of native bees. But native bees doesn't include
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the insect most of us picture when we hear the
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word be that yellow and black striped hive living honeymaking
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critter formerly APIs milifera, hails from Europe. Farmers rely on
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these tiny imports as essentially livestock animals that pollinate food
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crops and produce honey, but their wild native counterparts are
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something completely different. Quote take the majority of what you
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know about honey bees and throw it away, says Sidney Schumer,
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a biologist and manager of the US Geological Survey's Bee Lab.
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Quote it does not apply to our native bee friends.
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End quote. To celebrate spring, Scientific Americans spoke with Schumar
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about North American native bees, species, variety, differences from honey bees,
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and importance in their ecosystem. Do I have it right
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that there are more than four thousand native bees species
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in the US. How is that number so big? Well,
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the reason there's so many native bees is that you
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have all these different little things evolving to pollinate particular
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groups or species of plants, So they all have very
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different characteristics. When you look at pictures of our native bees.
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They look totally different than a honeybe and you have
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huge ranges of color, size, how they collect pollen, and
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how they nest. What are they like and how do
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they live? There are no native bees in North America
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that live in a hive or produce honey. Most of
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them live in very small family units. You could think
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of it more like an apartment where you might have
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families aggregating together. None of them produce honey, none of
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them produce wax. None of them make big structures like
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you would think with a honeybe. Some are stem nesters,
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most of them are ground nesters. So when you're walking
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around in the winter, you are walking on top of
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millions of ground nesting bees that are just laying low
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until it's time for them to come out in spring.
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Is this true even in cities? Do they have preferences
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or types of ground that they need. Many of our
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native bees are specialists, so they do like a certain
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type of soil a couple particularly like sand. In cities
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and more urban areas, you have a lot of impervious surfaces,
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which makes it harder for them. But if you have
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loose soil, if you have native plants, you're most likely
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going to find native bees. Are there any US ecosystems
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that don't have native bees, such as deserts. No. We
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worked on a project on Xeric habitats. That's x e
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ric and when you think of zeric, you think of drive,
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you think of nothing blooming, just arid. The researchers caught
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hundreds of bees. If you go anywhere in the US,
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you're bound to find some native bees. Are there any
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groups or species of bees that you find particularly cool?
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Besides all of them? I am very fond of squash bees.
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They're medium sized, very cute and fluffy, and as you
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might guess, they are squash specialists. They come out super
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early in the morning. You have to get there at
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first light, and if you have squash plants, then you
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most likely have them. The scientific name of the most
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widespread species is Piponipus pruinos up and you'll find them
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just relaxing in a big squash bloom. You mentioned that
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ground nesting bees are under foot all winter. What does
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a year in the life of a native bee look like?
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With more than four thousand species, they are not all
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coming out at the same time. You have some that
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emerge very early in the season, when the first spring
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ephemerals that's long lived plants that are only briefly active
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above ground start to bloom. In Maryland, that's typically around April,
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and then as you get the different flowers, you have
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this continuing crescendo of bees coming out. Usually you're seeing
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only a really small snapshot of a bee's life. Most
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of the time, bees exist as eggs and as a
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little larvae, and then they're in this weird grub form underground,
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and then they emerge as what we think of as bees,
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and that's when they're looking for food, finding a mate,
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and continuing that cycle all over again. Typically a bee
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is out for only maybe a month or two. They
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are kind of fragile. They have very thin wings and
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very thin antennae, so when you catch one, you can
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kind of tell if it's been out for a little while,
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if it looks somewhat battered it's been flying around and
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bumping into things and damaging its wings, or if it
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looks pristine, you can guess that it's recently emerged, or
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it's a little bit fresher than some of the other
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bees out there. Do the larvae and grubs look really
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different from an adult. They look more grub like, more
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caterpillar like. If you were to see one, you definitely
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would not guess that it's a bee. Larvae A lot
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of our native bees are very tiny, but they're not
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baby bees. Baby bees actually don't look anything like the
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bees we think of. They don't have the three segment body,
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they don't have six legs, they don't have wings, they
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don't have antenning. With honey bees, we see only females
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out and about is that the same with native bees.
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With native bees, there are very seldom queens. Bumble bees
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are the exception, but there are males and females. You
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do typically find more females and males, but you don't
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have the queens or the male drones, or those differences
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unless you're talking about the bumble bees. In general, most
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females and males do look a little different within the
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same species Under a microscope. Males have more coloration in
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the face or a bit more coloration in general, and
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they usually have long antennae compared with females. The biggest
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difference of all, even in native bees, is that females
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have a stinger and males do not. Can humans get
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stung by them? Then technically yes. Now the stinger is
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completely different from a honeybee. It's not as barbed stinger,
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which means one it's not as painful, and two, the
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native bee would not die after you get stung by it.
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That's the mechanism that kills the honey bee. The barbed
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stinger gets embedded. When the honey bee flies away, the
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stinger detaches, and the bee dies. A lot of the time,
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if people are stung by native bees, it's because they
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were handling them, actively netting them, or trying to grab them.
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That happens often with our bigger native bees, bumble bees,
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carpenter bees, things of that size. Everything else has such
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minuscule stingers that they're lucky if it even breaks the skin,
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much less through their clothing. Also, they're not very territorial.
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The main reason honey bees would sting you is that
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you're encroaching on their hive or they are resource guarding
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honting or flowers. Because native bees don't really have a
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hive to protect and also don't resource guard, you're a
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lot less likely to get in their way. Well, what
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do we know about how native bees are doing in general,
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native bee species are declining, and that is a result
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of habitat loss, pesticide use, more rural areas becoming urbanized,
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more impervious surfaces, and the like. If someone wants to
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start paying more attention to native bees, how easy is
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it to start learning to identify Bumble bees are the
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easiest to get started with, and there's tons of resources online.
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They're bigger. Typically you identify them based on the coloration
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of the hair on the back of the bee, So
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if one of them is just sitting on a flower,
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you can go up to it and figure out with
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decent certainty which one it is. Depending on your region.
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In terms of the other groups, it's hard. You definitely
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need a microscope and access to a reference collection where
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someone who's an expert has already identified some groups. Is
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there anything people can do to help native bees around them?
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The most well researched and well documented way of trying
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to introduce native bees to your area is to plant
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their habitat and plant their food source. It doesn't have
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to be anything crazy. Native bees are tiny. They're really small,
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So even if you have an apartment, if you have
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a little garden area or a pot, put some native
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plants in there, and I think you'll be astounded by
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what you wind up seeing. Come to visit and sticking
17:38
with Scientific American, we have this article dated April the seventh,
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NASA's Artemis era may finally solve three major Moon mysteries.
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Right now, all eyes are on Artemis two, NASA's historic
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mission that just sent astronauts around the Moon for the
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first time in more than a half century, but is
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detailed by NASA Administrator Jared Isaacman at the Space agency's
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ignition event in Washington, d C. Artemis III is only
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the beginning of a larger US effort to populate the
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Moon with astronauts and resource prospecting robots. If this quest
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advances at the breakneck pace that isagmund desires, then Earth's
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celestial sidekick will also become a place of profound scientific revelations.
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Despite the Moon being so nearby, we know surprisingly surprisingly
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little about it with much certainty. The Apollo astronauts hauled
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back a bevy of Moon rocks and left behind a
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few short lived geological experiments, but most of our lunar
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knowledge today comes from Moon orbiting satellites, telescopic observations from
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Earth and the handful of sample return missions undertaken recently
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by China. Starved of more in seat to data, researchers
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can't yet scratch a bigger scientific diitch. They wish to
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study the Moon as a Rosetta stone for the origin
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and evolution of our world and the Solar system at large. Now,
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thanks to the proposed high cadence of lunar missions crude
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and robotic by space agencies and private industry alike, it
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looks like their wish will be granted. Earth's tectonics, volcanism, oceans, atmosphere,
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and life have all erased the geological records of the
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planet's earliest eras, but the Moon, lacking such tumult has
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preserved them. That makes Earth's silvery orb a perfect geological laboratory,
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says Sarah Russell planetary scientists at London's Natural History Museum.
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With that in mind, here are the biggest mysteries Moon
19:56
focused scientists are now hoping to solve. How is the
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Moon still alive? Geologically speaking, the churning heat deep within
20:07
planets and moons is what gives them geological life. That's
20:11
in quotes from volcanic eruptions and earthquakes to uplifting mountains
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and excavating ocean basins. But when the heat wanes, a
20:20
world dies. Geologically speaking, scientists know of three main ways
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to keep the metaphorical fires burning. The primordial heat left
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over from impactors slamming together during the world's collisional formation,
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the heat from decaying radioactive elements, and the frictional heat
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from tidal forces that can need a world's innerds like dough.
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The Moon is much smaller than Earth, so its primordial
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heat should have leaked into space long ago. Lunar samples
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and theoretical models suggest it lacks a hidden abundance of
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radioactive elements, and careful calculations show that Earth's gravitational pulls
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shouldn't be causing significant lunar tidal heating. Yet shallow moonquakes
21:11
still shake the Moon. While age estimates based on crater
21:15
counts of its pock marked surface hint that some volcanism
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may be one hundred million years old, which on geological
21:24
time scales is yesterday. Scientists naturally have questions. Is the
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Moon still volcanically active? Asks Thomas Waters, senior scientists at
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the Center for Earth and Planetary Studies of the Smithsonian
21:39
to find out just how much geological life still lingers
21:42
there and why. Quote we need to get a better
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look at the Moon's internal structure, Water says, to delve
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to the geological heart of the matter. Scientists want to
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know the Moon's deepest secret. What's happening at its most
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abyssal debt depths. Does the Moon have a solid core
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or liquid core? Says Yuki Kon or Chon qi An,
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a lunar geologist at the University of Hong Kong. Quote
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we still don't know. Seismometers offer silver bullets, allowing scientists
22:20
to use moonquakes, whether homegrown or imported via lunar impacts,
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to effectively perform a CT scan of the deep subsurface,
22:30
but coverage is currently non existent. What we know about
22:33
the lunar underworld was provided by Apollo era seismometers that
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operated until nineteen seventy seven, and these were all placed
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in just one patch of the Moon's near side. Quote
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we don't have any seismometers deployed on the far side.
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Cheon says. That's about to change if current projections are
22:55
to be believed. The next time anyone lands astronauts on
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the Moon will be the Artemis for mission set for
23:01
twenty twenty eight. When those crew members reach their landing
23:05
site near the Moon's south pole, they'll towed along a
23:08
cutting edge seismometer package called the Lunar Environmental Monitorings That
23:12
Monitoring Station, or l EMS. Eventually, as part of NASA's
23:18
Commercial Lunar Payload Services, a network of sensors known as
23:22
the Far Side Seismic Sweep SWEET will be robotically deployed
23:28
in the eponymous region. Recent news suggests China may make
23:33
its first crude landing somewhere on the Moon's near side,
23:36
and those astronauts will likely bring seismometers as well. In
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other words, the Artemis astronauts will be laying down some
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of the first nodes of a global seismic network, says
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Nicholas Schmerr, seismologist and planetary scientists at the University of Maryland.
23:55
Samples too, will be vital rocks nabbed by China's robotic
23:59
lunars ample return missions. The change five and six indicate
24:04
active volcanism there up until at least two billion years ago.
24:09
Widening our view to the Moon's more recent epos requires
24:13
nabbing more youthful material from the surface for now, Cheon
24:17
says we don't have samples younger than that. Scientists also
24:21
hope future landings will locate in sample expunged sections of
24:25
the Moon's mantle, the primeval less altered underbelly of the
24:30
lunar crust. If mantle rocks prove to be riddled with
24:34
byproducts of radioactive decay, this would probably mean the Moon's
24:38
interior is richer in heat generating radioisotopes than scientists had thought,
24:44
thus explaining why it's still convulsing long past its presumed
24:49
geological expiration date. How did the Moon form? The most
24:56
popular origin story involves thea Hia, a Mars sized protoplanet,
25:04
smashing into the primordial proto Earth, with the debris from
25:08
both bodies quickly coalescing into the Moon. This isn't just
25:12
a fable, It's backed up by robust computer simulations grounded
25:16
with plenty of geochemical evidence. Samples of the Moon's mantle, though,
25:22
could further test this theory, while geophysical observations could address
25:27
the Moon's weirdest feature. The near side is covered in vast,
25:33
dark splotches of cooled volcanic rock named mara that's Latin
25:37
for c The far side has a dearth of these
25:41
and instead looks more like mercury, a crater filled land
25:44
of jagged mountain ridges. Why is the moon so two faced?
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One possible explanation comes from an idea dubbed earthshine. Eons ago,
25:53
when the Moon formed, it orbited Earth fifteen times closer.
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At some stage, the Moon became tidally locked, meaning one
26:01
hemisphere the near side always faced Earth, and because our
26:05
planet back then was a seething ball of magma, the
26:08
lunar near side should have been baked like crimber lay,
26:11
with the near side turning molten and bubbly streams of
26:14
vaporized rock whooshed around the Moon, cooling and raining out
26:18
on the far side to create its thick, lumpy crust.
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Here too, seismology offers another silver bullet. A network of seismometers,
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especially on the far side, could reveal crucial, otherwise hidden clues.
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What is the structure of the moon? Russell asks? This
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is important to find out, as it will help us
26:38
understand how the moon first formed from the debris of
26:41
a giant impact, and how it then evolved, and where
26:46
did the Moon's water come from. NASA really wants to
26:49
plock its astronauts down near the lunar south pole, because
26:53
that's where permanently shadowed craters harbor some vague amounts of
26:57
water ice, a potential resource for hydrating humans, growing crops,
27:03
and making rocket fuel. It's no coincidence, then, that lunar
27:07
prospecting was a hot topic of NASA's Ignition event. Astronauts
27:11
could in principle descend into the treacherously dark and cold
27:15
craters to look for them to look for themselves, but
27:19
most of this water dividing will be conducted by robots.
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NASA's Volatiles Investigating Polar Exploration Rover or VIPER will use
27:30
its instruments to sniff out subsurface water and then use
27:33
a drill to confirm its suspicions, and NASA's next generation
27:38
Moonbuggy or the Lunar Terrain Vehicle LTV, will do something similar,
27:43
whether it's being piloted by astronauts or as will likely
27:47
be the case for most of its lunar tenure, autonomously
27:50
navigating the surface and brought along for the ride on
27:54
an upcoming crude surface mission, will be the Lunar Dielectric Analyzer,
27:59
an instrument that can detect electrical currents in the ground
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which can reveal the presence of ice. This will really
28:05
help us understand where water is on the Moon and
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in what form. Russell says. That's all for today's Diary
28:13
of Science and Nature. Your reader was Kelly Taylor. Now
28:15
stay tuned for further programming on RADIOI