S27E80: Asteroids’ Close Calls, Mars Colonization Plans, and Space Workouts on Earth

[00:00:00] This is Space Time Series 27 Episode 80 for broadcast on the 3rd of June 2024. Coming up on Space Time. Two asteroids swoop past the Earth. New research to work out how the first people on the red planet Mars will live.

[00:00:16] And how to practice a space workout when you're on planet Earth. All that and more coming up on Space Time. Welcome to Space Time with Stuart Gary. The European Space Agency has reported two large asteroids swooping past the Earth just 42 hours apart.

[00:00:51] The rarer occurrence didn't pose a risk to the planet, but one of them, 2024MK, was only discovered two weeks before its closing counter with the Earth. That discovery clearly highlights the need to continue improving Earth's ability to detect potentially hazardous near-Earth objects or neos in our cosmic neighborhood.

[00:01:11] Asteroid 2024MK was somewhere between 120 and 260 meters wide. It zoomed past the Earth on June 29th, coming to within 290,000 km of the planet's surface. That's a close call in astronomical terms. Now there was never any risk of the asteroid actually impacting the Earth,

[00:01:30] however an asteroid of that size would have caused considerable damage if it did hit. The second celestial visitor was the massive 2310m wide asteroid 4159-2011UL21, which is a giant larger than 99% of all known near-Earth asteroids. Now luckily its Earth flyby was at a safe distance,

[00:01:53] some 17 times further away than the orbit of the moon. This asteroid's orbit around the Sun is steeply inclined, which is unusual for such a large object. Normally most large objects in our solar system, including planets and asteroids,

[00:02:07] tend to orbit the Sun in or close to the equatorial plane or ecliptic. This monster-strange orbit could be the result of gravitational interactions with a large planet like Jupiter. See, Jupiter can often deflect previously safe asteroids inwards towards the Earth,

[00:02:23] so it's important for astronomers to better understand the process. In this case, we know the asteroid has an 11-34 resonance with the Earth. That means it completes 11 orbits around the Sun in exactly the same amount of time it takes the Earth to complete 34 orbits.

[00:02:40] Both these celestial visitors encountered with the Earth just happened to coincide with World Asteroid Day. The United Nations-induced World Asteroid Day commemorates the largest observed asteroid strike in recorded history. That's the 1908 airburst above Tunguska in Siberia. It was on the morning of June 30, 1908 that a massive explosion

[00:03:02] with the force of a 5-megaton thermonuclear bomb, best equivalent of the 1,000 Hiroshima atomic bombs, smashed into northern Siberia. The blast was so powerful it lit up the night sky in London with an orange glow, a third of the way around the planet,

[00:03:19] allowing Brits to read their evening newspapers without turning on the lights. Seismographs 1,000 km away also recorded the event sparking intense scientific interest. Researchers were able to triangulate the blast to the remote Tunguska River region of northern Siberia.

[00:03:37] But the place is so isolated it took 19 years for a scientific expedition to reach it. What greeted the team when they arrived was a scene of utter devastation. The entire landscape had been flattened. The massive explosion shattered some 80 million trees over an area of more than 2,000 square kilometres.

[00:03:58] Mature trees were snapped off at their bases like mat sticks, covering the ground for hundreds of kilometres. And all were pointing away from the epicentre thought to be at the location of what these days is Lake Chico. The locals who witnessed the blast

[00:04:13] described a column of blue light that moved across the sky in the cool summer's morning air. And that was followed by a sudden tremendous explosion. Now, both the explosion and the eyewitness accounts were all consistent with an asteroid impact. But mysteriously no crater was ever found.

[00:04:31] And that led scientists to speculate that this asteroid probably airbursts before reaching the planet's surface. The idea of an airburst was also consistent with one very unusual characteristic of the impact site. All the flattened trees pointed away from the blast zone,

[00:04:47] all that is except those at ground zero. They remained upright. Computer simulations in the years since have supported the idea of an airburst explosion probably caused by a meteor between 1 and 200 metres across. Now if it was a meteor, it probably came from the beater towards Meteor Shower,

[00:05:06] a debris trail left behind by the comet 2P Enki which the Earth passes through every June and October. Enki itself is thought to be a piece of a larger comet that probably broke apart between 20,000 and 30,000 years ago following numerous interactions with a powerful gravitational field of Jupiter.

[00:05:25] Now as their name suggests, the torrid's meteor shower radiant, that is the apparent point of origin, lies in the constellation of Taurus the Bull. Generally speaking, the torrid's meteors are made up of larger, more massive material than most meteor showers. Think of pebbles instead of dust grains.

[00:05:42] That's because as well as the usual debris produced by comets as they degas and spluttering fragments into space from evaporating volatile materials, Enki's also encountering gravitational tidal forces from Earth and other planets causing larger chunks to break off. And all this makes the torrid's stream of material

[00:06:00] the largest in the inner solar system. Since the meteor stream is rather spread out in space, Earth takes several weeks to pass through it, causing an extended period of meteor activity compared with a much smaller periods of activity in other meteor showers. Included in the torrid's stream

[00:06:17] is a denser flow of gravelly meteoroids called the torrid's swarm, thought to be a ribbon of rocks roughly 75 million by 150 million kilometers across and shepherded together by Jupiter's gravity. Occasionally Earth passes through the larger meteoroids in the denser torrid's swarm

[00:06:35] and it's thought that it was one of these larger chunks in the torrid's swarm that may have caused the infamous Tunguska event. And that hypothesis has been supported by an examination of mineral debris trapped in peat from the blast area in Siberia.

[00:06:49] The debris was collected in the 1970s and 80s and scientists using high resolution imaging and spectroscopy identified polycrystalline aggregates of carbon minerals, diamond, lonsdellite and graphite. And we know that nanometre-sized particles of lonsdellite form together with diamond and graphite particles

[00:07:08] in carbon rich material that's been suddenly hit by a shockwave such as that generated by a meteor impact. Scientists also found iron, nickel, alloys, trolite and tainite together with tiny inclusions of iron sulfides all of which are often found in meteorites.

[00:07:24] So the meteor composition fan of the Tunguska peat appears to be the microscopic vestiges of the largest meteor impact in recorded history and very similar to that found in the Canyon Diablo meteorite which produced a famous Baringer impact crater in Arizona better known as Meteor Crater.

[00:07:43] However, there's still a problem with all this. See at Tunguska, there's still no major debris from an airburst. And that's unusual because when a 20-meter wide meteor airbursts in the Siberian skies above Chelnia Blinsk back in 2013, fragments from the space rock were found scattered

[00:07:59] across a wide area of the landscape and in a nearby lake. But other than the microscopic sized iron, nickel grains, no fragments of the Tunguska meteor have ever been found. One hypothesis which was reported in the monthly notices of the Royal Astronomical Society argues

[00:08:15] that there were no meteorite fragments because the asteroid didn't fragment after all. Instead, it simply glanced off the Earth's atmosphere. And while that might sound fantastic, the simple fact is meteors have been known to skip across the atmosphere. One example being the giant daylight fireball

[00:08:32] caused by a space rock the size of a bus glancing off the upper atmosphere above Utah and Wyoming back in 1972. Scientists use computer modeling to explore several different scenarios looking at different sized meteors traveling at different angles and velocities. They found that an iron meteoroid about 200 meters

[00:08:51] across coming within 10 kilometers of the Earth's surface at a shallow angle would have remained largely unscathed and continue orbiting the sun. They say the rapid compression of the air near the asteroid would be enough to create the blast region observed. Overall, Tunguska represents a lucky escape for Europe.

[00:09:10] It happened just a short rotation of the Earth away from affecting the continent's most heavily populated regions. Over the last two decades, NASA and ESA have been performing detection analysis of potentially hazardous neos. Current estimates suggest there could be more than 5 million neos out there

[00:09:28] larger than 20 meters in size. That's the threshold above which an impact could cause damage on the ground. Right now, ESA's planetary defense office is carrying out a number of projects dedicated to improving astronomers' ability to detect, track and mitigate potentially hazardous asteroids. For example, launching later this year

[00:09:48] will be ESA's HERA mission. That's part of the world's first test of asteroid deflection. As we mentioned in last week's show, HERA will perform a detailed post-impact survey of the asteroid dimorphus. Dimorphus was impacted by NASA's DART mission back in September 2022. The impact of DART successfully changed

[00:10:07] dimorphus' orbit around its host asteroid, Diddymos, shortening it by 32 minutes. HERA will study the impact site and surrounding areas, turning the experiment into a well understood and repeatable planetary defense technique. ESA is also developing a network of insect inspired fly-eye telescopes

[00:10:27] that'll use their uniquely wide field of view to automatically scan the entire skies every night, looking for new potentially hazardous near earth asteroids. And ESA's future Neomy satellite will be located between the Earth and the Sun. It'll use infrared sensors despite asteroids approaching the planet

[00:10:45] from regions of the sky, which can't normally be seen from the ground as they're obscured by the glare of the sun. Then there's ESA's fireball camera in Spain, which captured a stunning meteor during the night of May the 18th and 19th this year.

[00:10:59] That was thought to have been a small piece of a comet, which flew over Spain and Portugal, travelling at roughly 162,000 km per hour before burning up over the Atlantic Ocean. And just a couple of weeks later, on June the 6th, the Catalina All-Sky Survey

[00:11:15] in Arizona also discovered a small asteroid about four metres in size, which triggered an alert from ESA's imminent impact monitoring system, MEKAT. Luckily that alert was not for an impact, but for a very close call. And just a few hours later,

[00:11:31] the object flew over the Catalina Sky Survey telescopes at a distance of just 1,750 km, making it only the second closest pass ever of a known non-impacting asteroid. This space time. Still to come. How the first people living on Mars will survive

[00:11:51] and practicing a space workout here on Earth. All that and more still to come on spacetime. When the first humans travel to Mars in the next decade or so, they're simply not going to be able to take all the food they'll need with them.

[00:12:21] See, a trip to the red planet will take at least six months each way. Then there's the problem of how long do you stay? Do you spend all that time travelling for just a week or two on the red planet's surface before heading back,

[00:12:34] while the orbital alignment still allows a quick return trip? Or do you commit yourself to a much longer two-year habitation on Mars waiting until the next Earth-Mars planetary alignment arrives? Either way, it's still going to take an awful lot of supplies,

[00:12:49] enough to sustain a crew for either 12 months or three years. While most will be seven supply missions in advance, self-sufficiency far away from Earth will still be a key part of any strategy. See, going to Mars isn't like a quick trip to the International Space Station,

[00:13:05] which can be reached in just a few hours with fresh supplies. Even the manned journeys to the Moon can be resupplied in just three days. But the first humans to travel to the red planet will involve a totally different type of spaceflight. Right now, Utah State University scientists

[00:13:23] Bruce Bugby and Lance Seafelt are working on a five-year NASA-funded multi-institutional project exploring self-sustainability on missions to Mars and beyond. Bartonis, Bugby, and biochemist Seafelt are among the principal investigators working on cubes, a centre for utilisation of biological engineering in space. Cubes is developing the supporting biotechnology

[00:13:45] needed for deep space exploration. It's looking to optimise food and plant-based therapeutics in space as well as to enable the production of biomaterials and energy. Seafelt says getting supplies from the Earth to Mars is too slow and too costly. Because of this, Mars explorers will need to generate

[00:14:04] their own food, their own pharmaceuticals, and a lot of their own infrastructure. He says as part of that effort, Martian greenhouses will need to be constructed, most likely underground, to withstand the planet's harsh environment. So Cubes researchers are working on ways

[00:14:19] to supply growth chambers with sunlight and nutrients. Fellow researcher Bugby says the team are also working to find out which kinds of plants, including rice, lettuce, potatoes and possibly soybeans, can be successfully grown on the red planet and will be capable of providing nutritionally-sustaining diet.

[00:14:38] This report from Utah State University. Three, two, one, boosters indignation. And liftoff of Artemis I. We rise together back to the moon and beyond. Humanity is headed to Mars. NASA's Artemis missions, currently ongoing and in process, have the express goal of not just revisiting the moon,

[00:15:00] but to learn how to live and work on another world as we prepare for human missions to the red planet. But back here on Earth, USU is working on a NASA grant to learn how to grow plants for these missions. Even with our greatest technology at this point,

[00:15:13] that transit to Mars is still going to be a year, a year plus. We can't necessarily take enough food and have it last for that long, for that trip to Mars, whatever we do on Mars, and that transit path. So NASA tasks knowing, along with Bruce Bugby,

[00:15:28] Lance Seedfeld and other graduate and PhD students in figuring out how we could grow plants like lettuces with what's available on Mars. Mars has nitrogen in the atmosphere. There's plenty of nitrogen to grow plants for hundreds of people for 100 years. We just have to fix that nitrogen

[00:15:50] in a bioavailable form for the plants. To do this, Lance worked with his research team to identify a microbe that would do just that, capture the atmospheric nitrogen and make it available for our space-faring plants. If we take the bacteria and we feed them the atmosphere from Mars

[00:16:08] and we feed them light, they will then capture that gas, that atmospheric end, too, and turn it into what's called a fixed form of nitrogen. And that fixed form of nitrogen then is part of the biomass that sort of ends up looking like is like peanut butter.

[00:16:22] It's a dry, sort of wet-ish, dry paste that you can then use that mobilize that to feed the plants in hypoponics. That means that the astronauts would only need to bring a starter kit of sorts, and then the whole system is designed to be recycled

[00:16:35] and recultivated time and time again. And this has applications here on Earth as well. So we also, plants need nitrogen on Earth, of course, as well. And we end up wasting a lot of nitrogen from those fertilizers. We want to be able to use this research

[00:16:51] to help producers, to help growers maintain their nitrogen stores in that soil, out in their fields, to produce the most efficient plants that they can. And in that report, we heard from Noah Langenfeld from the Crop Physiologist Laboratory, Bruce Bugby, director of the Crop Physiologist Laboratory

[00:17:12] and Chemistry and Biology professor, Lance Seafelt. All are with Utah State University. This is space-time. Still to come. Practicing a space workout on Earth, and later in the science report, a new study has found that alcohol is responsible for some 2.6 million deaths annually.

[00:17:33] All that and more still to come on space-time. One of the big problems of working in microgravity is the need to keep fit. Muscles tend to lose mass and bones tend to lose density in the weightless conditions of space.

[00:18:03] And so astronauts spend a great deal of their time working out just to keep in good shape. And while an out-of-this-world workout can keep astronauts fit on the space station, it seems you too can practice that here on Earth.

[00:18:16] That's as long as you've got access to a wall of death and some bungee cord. Walls of death are those semi-spherical bowls in which motorcycle riders like to travel around in their tests of bravery. Researchers ran horizontally around the motorcyclists' wall of death

[00:18:32] whilst being held in place by bungee cords in order to mimic the moon's gravity. Running this way allows centrifugal force to simulate the higher levels of gravity. The new findings reported in the Journal of the Royal Society Open Science suggested it would be possible

[00:18:47] to recreate Earth-like forces needed to maintain fitness in space. This is space-time. And time now to take another brief look at some of the other stories making news in science this week with the science report. A new study by the World Health Organization claims that alcohols responsible

[00:19:21] for some 2.6 million deaths each year. The report found that 7% of the world's population aged 15 years and over have an alcohol use disorder and problematic alcohol and other drug use continues to have a major impact on health and development around the planet. The report outlines various strategies

[00:19:41] to reduce the use and misuse of drugs and alcohol in order to meet upcoming health targets including strengthening healthcare systems, training health professionals and increasing awareness of the risks of drug and alcohol consumption. Scientists tracing the family tree of psalmium plants that's a group in the nightshade family

[00:20:01] which includes red tomatoes, purple eggplants and potatoes have found that while they're incredibly diverse in colors and sizes their evolution actually follows some common guidelines. A report in the Journal New Physiologist by researchers at Penn State University found that the size and color of these fruits

[00:20:19] all evolved together and that fruit-eating animals weren't the primary drivers of these fruits' evolution as had been previously thought. The findings may provide fresh insights into breeding these agriculturally important plants with new more desirable traits. There are some 1,300 known species of the genus psalmium.

[00:20:38] That makes it one of the most popular and diverse plant genera in the world. The authors collected samples from across the planet including wild plants from Brazil, Peru and Puerto Rico as well as many other specimens from botanical gardens in order to sequence their genes from RNA.

[00:20:54] They ultimately compared the sequences of some 1,786 genes from a total of 247 species in order to reconstruct the family tree. The authors found that the color and size of psalmium fruits was fairly conserved over evolutionary history, meaning that closely-rated species tend to have similar fruits.

[00:21:15] And the evolution of fruit color and size also correlated with changes in one trait often corresponding to changes in the other. That led to fruits of certain colors ending up bigger than fruits of other colors. The results suggest that physiological and molecular mechanisms may play an important role

[00:21:32] in keeping the evolution of fruit color and size tied together. New research presented to the conference of the Federation of European Neuroscience Society's Forum claims that while people aren't very good at distinguishing between human voices and those generated by artificial intelligence, imaging people's brains showed

[00:21:52] that those little gray cells react quite differently when they hear a voice generated by AI compared to one generated by a real person. The authors played clips of both human and AI-generated voices expressing different emotions to 43 people. They found participants were only able

[00:22:09] to correctly identify human and AI voices around half the time. But by scanning their brains, scientists found that human voices more often showed up in areas of the brain associated with memory and empathy and the AI voices elicited responses from the error detection

[00:22:26] and attention regulation areas of the brain. Samsung have announced the launch of their unpacked showcase for July the 10th, the event which will be Samsung's biggest in years will feature loads of new AI powered tech. With the details, we join by technology editor

[00:22:44] Alex Saharov-Royt from Tech Advice Start Life. Yes, Samsung is launching its Galaxy unpacked event in Paris July 10th 2024. They're gonna have the new six generation fold and flip devices in those dead series. Full of AI and they should have new watches and I'm sure they'll have new tablets

[00:23:01] so it'll be their ecosystem of devices infused by AI and they're saying get ready for a world of possibilities as we enter a new phase of mobile AI. So they clearly wanna go dump Apple and Google as best as you know, Microsoft as well as best they can.

[00:23:14] So we'll have more on that when it launches. So Google have got another announcement? Yeah, well on the same day Samsung's announcement, Google said that they're launching their made by Google event with a launch to Pixel 9 and 9 Pro and most likely their third generation watch

[00:23:27] and probably a new tablet as well and it'll have all of Android 15 plus the new AI enhancements that will be obviously even better than what they thought before and informed by what OpenAI and Apple have launched in their most recent events

[00:23:38] and they're doing it on August the 13th in the US so that's two months earlier than when they normally would normally it's a month after the new iPhone launches. So Google wants to capture the heart, minds and wallets of consumers as does Samsung and does Apple.

[00:23:51] And SpaceX hasn't been left out either. Elon Musk has launched his new portable Starlink dish well it's a Squish but yeah. Yes, it's called a Starlink mini and it's being offered to existing Starlink users in the US and Canada for US $599. Now it weighs 1.13 kilograms

[00:24:08] so it fits the plant lighter than the standard dish and there's a little kickstand because the dish that can fit into a backpack it's got a wifi router as well so you can set it up anywhere that you've got line of sight effectively. Now it's $150 per month

[00:24:22] with a 50 gigabytes speed cap dollar I think $1 a gigabyte thereafter the download rate is 100 and I think it's 25 megabits up but in any case it's broadband on the go and not available in Australia yet but it is ubiquitous communications from just about anywhere. That's Alex Sahara of Royd

[00:24:39] from TechAdvice Start Life and that's the show for now. Space Time is available every Monday, Wednesday and Friday through Apple Podcasts iTunes, Stitcher, Google Podcasts, Pocket Casts, Spotify, A-Cast, Amazon Music, Bytes.com, SoundCloud, YouTube, your favorite podcast download provider and from spacetimewithstewittgarry.com Space Time's also broadcast through

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