Comet Confusion and the Psyche Mission's Mars Encounter

This is Spacetime Series twenty nine, episode ninety one, for broadcast on the thirty first of July twenty twenty six. Coming up on space Time, the Nearest asteroid that turned out to be a comet, massas Psyche spacecraft's gravity assist flyby of Mars, and China's about to double the size of its space station. All that and more coming up on Spacetime. Welcome to Spacetime with Stewart Gary. Astronomers have confirmed that the Nearest asteroid, nineteen ninety eight s H two is actually a comet, further blurring the lines between these two different types of celestial bodies. The problem was the object originally looked like a typical asteroid in most telescope images, showing none of the usual comet like characteristics such as degassing, a fuzzy coma nucleus, and cometary tails. But the unusual thing was this asteroid was on a comet like orbit. The new findings were reported in the journal Nature Astronomy based on fresh more detailed observations. The puzzle began back on August twenty eighth, twenty twenty five, when nineteen ninety eight SH two passed within three million kilometers of the Earth. During its four and a half year orbit around the Sun, astronomers took the opportunity to observe the asteroid with NASA's Deep Space Network Planetary radar system. They had calculated its position using data from previous orbits and factored in the effects that the gravity of the Sun and planets would have had on its path. But when the asteroid didn't show up where they expected, they realized that something unanticipated must have been influencing its motion through space. By using optical astrometry to precisely measure the object's position in the sky, they were finally able to identify the cause. Studies lead auth to David Fernerccia from NASA's Jet Propulsion Laboratory in pasad Into, California, says that after measuring the non gravitational perturbations affecting the motion of nineteen ninety eight SH two, his team recognized that they weren't compatible with the object being an asteroid and began to suspect that it may well be an active commerce instead. Although nineteen ninety eight SH two's orbit around the Sun has been well tracked, from nineteen ninety eight to twenty sixteen, the object had completed two solar orbits since then without any additional observations. Analyzing all the observations collected since the object's discovery back in nineteen ninety eight, the authors determined the perturbations too nineteen ninety eight sh two's motion and hypothesized that the object must be generating a small amount of its own thrust, possibly by venting gases into space, and that was what was causing it to deviate from its projected path. Now. This venting results from the sun heating ices mixed with rocky material, turning the ice into a gas. With regular comets, this activity forms the trademark bright tail and coma as the gas and dust surrounding the comets nucleus. But when an object produces its gas and dust in much smaller quantities, its tail and coma may not be detectable by most observatories. So the August twenty twenty five close approach to Earth provided the perfect opportunity for for Nurture and colleagues to gather observational evidence for any possible visible cometary activity. They use the Canada Frantz Hawaii Telescope on Monacau, as well as the European Southern Observatory's Danish telescope at Lacilia and its VEL two or very large telescope at Parnell, both in Chile, to study this object in more detail in the process, revealing a weak but clear cometary tale. As a result, nineteen ninety eight SH two has now been given an additional cometary designation P nineteen ninety eight SH two. The findings also shed light on another even more unusual class of objects, known as dark comets. Like P nineteen ninety eight SH two, dark comets exhibit significant irregularities or perturbations in their trajectories, but they lack other visible evidence of comet like activity. There's no coma, no tail, and no visible outgassing. These distinct objects fall into two distinct populations, larger ones with orbits similar to those of Jupiter family comets. These are short period comets with highly elliptical or eccentric orbits, and smaller comets that orbit closer into the Sun. Since the twenty sixteen discovery of the first dark comet, that a dozen more have been identified. The author suggest that many of the larger dark comets, which have orbits like P nineteen ninety eight SH two's could turn out to be regular comets. That's if astronomers can get the opportunity to observe them with more powerful telescopes ones capable of imaging incredibly faint objects. Fernature says the work shows the importance of continuously tracking near eth objects. Detecting these perturbations would be an important diagnostic tool for planetary defense that will help astronomers understand which objects may be commets rather than asteroids, how their orbits evolve, and how that could influence their chances of impacting the Earth. This is space time still to come NASAs Psyche spacecraft undertakes the successful gravity assist fly by over the red planet Mars, and as NASA prepares to wind down in the orbit the International Space Station, China announces plans to double the size of its own space station. All that and more still to come on space Time. This episode of space Time is brought to you by NordVPN, space Time's official VPN service. Let's face it, these days, your online privacy is more important than ever. Whether you're streaming science documentaries, reading the latest research, or exploring deep space images. 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And of course the whole thing is risk free with a thirty day money back guarantee, so you've got nothing to lose and your online freedom to gain. So protect your digital life, support space time and grab our exclusive offer now at NordVPN dot com slash Stewart Gary. That's NORDVPND slash Stewart Garry. NASA's Psyche spacecraft has undertaken a successful gravity assayst flyby of the red planet Mars, a maneuver which will help slingshot the probe to its ultimate target, the strange metallic asteroid sixteen Psarchi, the two hundred and twenty six kilometawide metal rich asteroid orbits the Sun in the main asteroid built between Mars and Jupiter. It contains about one percent of the entire mass of the main asteroid belt and is primarily composed of iron, nickel, and precious metals, giving it a hypothetical mining valuation exceeding ten quintillion US dollars. Psaki was originally chosen for the mission because it was thought to be the exposed metallic core of a larger, differentiated planetary body which had its metal and cross stripped away during some sort of ancient impact event. That made Psyche a prime target for astronomers wanting to study the internal structures of planets. However, as they began getting more and more data on the asteroid. There received mass and density observations that were inconsistent with Psyche being a remnant planetary core. That led to a new hypothesis suggesting that Psyche had been disrupted and then gravitationally reaccreted into a mix of metal and silicates that would make it a potential parent body for the meso cyderites class of stony iron meteorites. Another hypothesis suggests that Psyche may be a differentiated object like Serious Investor, but one that experienced a type of iron volcanism called ferr volcanism while still curling. Now. If correct, this model predicts that metal would be highly enriched only in those regions containing relic volcanic centers of view, supported by recent radar observations. Meanwhile, by this time, the Psyche spacecraft or relaunched on its mission. It aated its close encarter with Mars, using the pl and its gravity to gain speed and slightly tilting its trajectory. The flyby also gave mission managers an opportunity to prep for the science they'll be conducting when they finally reached the middle rich asteroid Psyche. In twenty twenty nine, they tested the spacecraft science instruments, confirming all were operating nominally, providing data that match to what NASA already knew about Mars, and also providing a few new insights about the red planet along the way. Psyche's principal investigator, Lindy Elkins Tantent from the University of California, Berkeley, says the spacecraft's imager, MAGNETOMETA, and gamma ray in neutrons spectrometer teams all worked overtime to make full use of the planetary encounter, and all instruments delivered great results. The gamma ray in neutrons spectrometer, which helped scientists determine the chemical elements that make up the asteroid surface material, got a real workout during the flyby as high energy cosmic rays bombarded Mars. Elements on the red planet's surface absorb energy many neutrons and gamma rays of varying energy levels. By measure these emissions, scientists can match them the properties of known elements in order to determine what the body's made of. Or The Mars fly by altitude of four thousand, six hundred nine kilom as was too far away to measure gamma rays neutrons escaping the planet's surface and atmosphere could be detected. The mission's magnetometer is designed to measure Psyche's magnetic field, and it was designed to test the idea that it could be the metallic core of a planet tesimal, the building block of a rocky planet. While this instrument's been constantly measuring the solar wind's magnetic field throughout its cruise phase, including when occasional chronal mass ejections washed over the spacecraft, Mars was the first magnetic field signature of a celestial body that the magnetometer was able to measure. As the spacecraft passed close to the red planet, the magnetometer saw an increased uptick in magnetic field, corresponding to the bowshock region, where the solar wind slams into the planet's magnetic field. Meanwhile, the spacecraft's Multi Spectral imager, a pair of identical cameras designed to photograph the surface of the asteroid in different ways lengths, delivered some stunning views of Mars during the flyby. Because of the high phase angle at which the spacecraft approached the red planet, Mars initially appeared as nothing more than a thin, bright crescent with sunlight scattering through its atmosphere. During close approach, the imager team captured detailed views of the Martian surface, including windblown craters, the South Polar ice cap, the large double ringed Huygen's crater, and the two Martian moons, Phobos and de Mos. Psychi project manager Bob Mays, from massa's Jet Propotional Laboratory in passing into California, says that Psychi spacecraft remains in great shape and is now headed directly towards its ultimate target. He says the probes on schedule to resume sustain thrusting using its solar electric proportion system in a couple of months time. This report from mass A TV. For a fleeting moment. On May fifteenth, twenty twenty six, NASA's Psyche spacecraft drew close enough to Mars to see its craters, calibrate its instruments, and then it kept going, coming within two eight hundred and sixty four miles of the red planet's surface. The Psyche mission got a critical gravity assist on its way toward the metal rich asteroid. Psyche analyzing radio signals between the spacecraft and NASA's deep space network Psyche's flight team confirmed Mars gave the spacecraft a one thousand mile per hour boost and shifted its orbital plane relative to the Sun by more than three degrees, setting it almost perfectly on its plan trajectory to arrive at Asteroid Psyche in the summer of twenty twenty nine. During the flyby, Psyche's imagers, magnetometer, and gamma ray and neutrons spectrometer instruments were powered up and collected data to take advantage of the valuable calibration opportunity the close approach offered, comparing its measurements to surface and atmospheric data from several other Mars missions. Psyche's spectrometer measured neutrons coming from the red planet's surface during close approach, something it will do at Asteroid Psyche to be understand what it's made of. The magnetometer detected Mars magnetic field interacting with the Sun's plasma as the spacecraft passed through the planet's bowshock, a trial run for when the instrument will measure the asteroid's magnetism, and Psyche's multi spectral imager was especially active. An event like this takes a ton of planning. We like to use a system called cosmographia to simulate everything in advance. You know, how close do we need those images to be as we pass really close to Mars in order to see enough of an overlap that we can make a huge mosaic out of it. That gives us a beautiful opportunity to see the big picture and to really put it all together. As a bonus, Psyche's multi spectral imager captured Mars from a rare perspective. Coming in at such a high phase crescent. Only four percent of Mars was illuminated, and with that we could see the atmosphere around it glowing. So you could see clouds on Mars. It was really quiet as the three of us just kind of sat back there looking at it. My favorite image is the one that looks like an and I love how it starts with Mars as a really tiny little crescent, and then every day it gets slightly bigger and slightly bigger until we have fourteen images stacked up, so it gives a nice perspective on the speed the spacecraft is traveling. Yet, the detail that we were able to see in some of these terrain I personally was blown away. The southern polar cap Puygan's Crater. I think the wind streaked terrain was really interesting. It shows like active processes happening on Mars. It was very exciting to be able to finally put the whole thing together and then ce Mars getting bigger and then smaller. In the field of view. Again, feels great to finally have more to share with the world. With Mars behind Psyche, the spacecraft will soon resume thrusting with its solar electric propulsion system. Next stop the asteroid belt onward to Psyche. And in that report from MESSATV, weird from Psyche multi spectral image of operations team members the Cole Gonzali's and Hannah Zigo, both from Arizona State University. This is space time still to come. China about to double the size of its space station, and later in the science report, new clues about how the human body's nervous system sensors warm and cool temperatures. All that and more still to come on space time as NASA looks at winding down and deorbiting the International Space Station in twenty thirty, Beijing has announced plans to double the size of its Tiangong space station The expansion will see the orbiting urposts transform from its existing three modules to six, in the process changing its layout from a T shape to a sort of cross or double tea. Included in the expansion will be a new twenty tom class multifunctional hub featuring six docking ports and an extra vehicle activity hatchess spacewalks, as well as two new modules also in the twenty ton class, all of which will combine to allow China to dramatically expand its operations. The changes will also increase the station's mass from seventy seven tons somewhere between one hundred and eighty and two hundred tons, and it will allow the station's permanent crew capacity to grow from the current three up to at least six targanauts at a time. The plans also include launching the new Hubble class Gune t in space telescope, which will fly in formation with a space station and occasionally dark with it for maintenance, refueling, and repairs, as well as potential upgrades. The new telescope will feature two meter primary mirror and a slightly smaller than the two point four meter mirror used on Hubble, and it will use a two point five billion pixel camera. June ten is scheduled fu launch next year and is expected to have at least a tenure lifespan. The first modules of Tiangong Mandarin for Heavenly Palace will launched back in twenty twenty one, with crews of three sheds of tarkanats serving on station at any given time. China's also developing new cargo ships to resupply the space station, and it's been developing its new seven man being Juice spacecraft, which will ultimately replace the current Russian based three man Shenzhu capsule. This is Space Time and time out to take another brief look at some of the other stories making years and science this week with a science report. Your research has challenged what scientists understand about how the body's central nervous system sensors warm and cool temperature. Scientists at the University of Queensland found that most of the skin's temperature sensitive nerve cells can sense both hot and cold. The findings, reported in the journal Neuron, challenges the widely accepted view that the skin relies on separate nerve cells to detect each type of temperature. A new study based in the Western Australian wheat belt is found alarming levels of pesticide contamination in the food sources of endangered Carnabi's cockatoos near seed spills and grain silos over three breeding seasons. Wild Carnabi's cockatoos were fitted with satellite tracking tags across five we built breeding sites in order to identify where and what they were eating. A report in the General Environmental Toxicology and Pharmacology claimed seed samples were then tested for pesticide contamination and the results showed concentrations well above regulatory limits. Scientists to found evidence of an ancient species of snake that lived almost exclusively underground. A reported the journal Nature, claims the species Tamater and miriam, a newly identified extinct snake species fat in Brazil, which lived around eighty five to seventy five million years ago, was adapted for life underground. That's in contrast to other early snake species that lived above the ground or in water. The authors say the newly discovered fossil includes a well preserved three dimensional skull and body, and is the first ner articulated snake fossil fat in Brazil. X rays of the remains show its skull was shaped for burrowing, and its brain was quite different from that of other snakes, both extinct and living, and this suggests snake evolution was far more dynamic than previously thought. A new study warns that working from home may not have a significant impact on your carbon footprint. A report in the General Plus Climate claims the emissions saved by not commuting are largely all offset by running a home office. The authors found that working more days from home and having a separate home office were both linked to higher overall the missions. And it wouldn't be Friday without a bigfoot story. There's been a span of eight bigfoot sightings over a period of just five days in the American state of Ohio. The Skeptics to Mendum says the sightings all occurred in the state's northeast, but they appear to have involved very different look eastad squatches. I've seen eight times in one week in Ohio in a small area of Ohio and Trumbull County. And this has been seen from people saying I saw it at a distance of about one hundred and twenty yards or so, when it was that one hundred meters nine foot tall brown heads that's what in the middle of the day, broad daylight, I saw it in then around af a, the other person said. The hiker said they spotted an eightful tall creature with dark brown hair sitting out from behind trees just forty yards away. And this one actually yelled at a deep, bechoing grunt. A terrified ex veteran generally actually being an x veteran relevance is but obviously ex military described feeling watched and hearing this hellish roar that left him scared. Obviously didn't see a scout clutter a bigfoot, And I mean a lot of sightings short period of time, five days, and I assume that they'se got publicity at the time, so you would respect that some people were inspired, were pre prepared, or someone you know, to actually see something of that. If they saw something strange, they think it's the big foot. The dogs apparently get really upset, shaking with fear, no diffinity proof, no photos. They said they's down a couple of footprints, but often if you see big footprints, not very convincing. Necessarily, there could be a lot of things. A lot of interpretation goes into these evidence. And I've seen footprints of spurt of Australia. But yeah, we king really, yeah, they don't look like foots. Sometimes very strong correlation between an increase in sasquat sightings and an increase in their populations. Yes, well, dear, maybe there's the sasquats there. Maybe there really is. It'd be fascinating to see. I think we'd all like to see something like that. It'd be very exciting. But as for proof of it, a lot of sightings in one short time is exciting, but not necessarily affinity proof. What I always say is that a bit of evidence which rates through out of ten because you don't have any other evidence of systemic datal is interesting. Eight bits of evidence that rate two out of ten. They not give you a ten out of ten. They give you a lot of two out of ten, right, And in fact, the more two out of tens to get, the less likely something is to be true, because you say, well, you've only got bad evidence, you haven't got good evidence. We've got a lot of bad evidence. We've got a lot of bad evidence. A phone with the camera. Then't including the X retro. It's a thing that people say it's happening all the time yeah, but it's happening badly all the time. It's not happening convincingly all the time, and the more non convincing it is to me, the less likely it is to be true. That's the skeptics timendum. And this is space Time, and that's the show for now. Space Time is available every Monday, Wednesday and Friday through at fyites dot com, SoundCloud, YouTube, your favorite podcast download provider, and from space Time with Stuart Gary dot com. 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