Gas Giants vs. Brown Dwarfs: Unraveling the Cosmic Spin Mystery

This is Spacetime Series twenty nine, episode thirty six, for broadcast on the twenty fifth of March twenty twenty six. Coming up on space Time, how to tell gas giants from brown dwarfs, a nuclear power station on the Moon gets to green light, and using an ice satellite to detect a powerful geomagnetic storm. All that and more coming up on Spacetime. Welcome to space Time with Stewart Gary. A new study has found that giant planets rotate faster than their cosmic brown dwarf look alikes. For decades, astronomers have struggled to differentiate gas giant planets from brown dwarves, a class of objects more massive than planets but too small to trigger the core nuclear fusion process which makes stars shine through a telescope. These cosmic look alikes and have overlapping brightness, temperatures, and even atmospheric fingerprints, and these similarities leave astronomers unsure if what they've observed is simply an oversized planet or an undersized star. Now are reporting The Astronomical Journal claims scientists have uncovered a crucial new clue that separates the two, namely how fast they spin. New observations have provided the clearest evidence yet that giant planet spin significantly faster than their brown dwarf counterparts. The new results suggests rotational measurements may provide a powerful new diagnostic till for classifying these two indistinguishable populations, but it also suggests that these two objects evolve very differently, perhaps even forming through distinctly independent processes. The study marks the largest survey of spin measurements of directly imaged extra solar planets and brown dwarfs ever undertaken. The studies lead author Chiechun Sou from Northwestern University says spin is a fossil record of how planets formed. By measuring how quickly these words rotate, astronomers can start to piece together the physical processes that shape them. Typically, astronomers can distinguish plants from stars based on a combination of brightness, temperatures, and spectral information, but gas giants and brown dwarves sit right in the blurry middle of this classification system. See The size and mass of the largest planets comes close to overlapping with the size and mass of the smallest brown dwarves. Brown dwarfs are failed stars with at least thirteen times the mass of Jupiter, the largest planet in our Solar system. They're also about eighty times less massive than the smallest stars known as spectro type M red dwarves, and because brown dwarves lack sustain nuclear fusion, they emit only a faint glow like a giant planet. The Steadies authors speculated whether or not a body's spin could provide a differentiating factor. They use the giant ten meter Keck twin telescopes amo A, Key and Hawaii to analyze spectroscopic observations of six gas giant exoplanets and twenty five brown dwarves. Spectroscopy can be used to isolate light from faint objects in order to measure the chemical composition of their atmospheres. They produce a series of spectral lines at very specific frequencies, and these correlate to specific chemicals. But they do another thing. These spectral lines will shift slightly depending on whether the target's atmosphere is moving towards you or away from you as the body revolves. This Doppler shift effect is similar to the change in picture here. When an ambulance siren moves past you, the light waves are compressed or blue shifted as they move towards you from the target, and they're red shifted or stretched as they move away from you. And by analyzing these data, astronomers can determine how quickly the objects spinning. After measuring the spins of the exoplanets and brown dwarves, authors combine their new measurements with sp observations from earlier studies, and a clear pattern started to become apparent. They found that giant planets tend to rotate at a larger fraction of the theoretical maximum speed known as their break up velocity. That's the point at which an object would tear itself apart through centrifical force, and by contrast, brown dwarfs rotate more slowly now. This difference likely traces back to the object's masses and how their mass compares with that of their host stars. Planets form within protoplanetary disks of gas and dust surrounding young stars during formation. Interaction with the disc can influence how much angular momentum or the amount of spin a planet retains. Brown dwarfs, on the other hand, can form like stars through the collapse of gas clouds, or alternatively, they may also form like planets. Interactions between the brown dwarfs strong magnetic field and the surrounding gas acts as a sort of cosmic break, causing the object to lose angular momentum. The study also found that brown dwarfs orbiting stars rotate even more slowly than isolated brown dwarfs which are drifting through space, and this possibly reflects different formation environments. This is space time still to come. NASA in the US Department of Energy give a green light to the construction of a nuclear power station on the Moon and using an ice satellite to study powerful germ magnetic storms. All that and more still to come on space time. NASA in the United States Department of Energy, ever renewed their partnership that develop a nuclear fission reactor on the Moon. It'll be used to power permanent base on the lunar surface, which is expected to be established by twenty thirty. NASA now planning to return humans to the Moon in twenty twenty eight aboard the atomis formission. The base will be located at the lunar South Pole and will provide energy for sustained human and robotic activity on the surface. The partnership calls for the two agencies to develop fuel and ready efficient surface power system for launch and deployment on the Moon. The Modula nuclear reactor system will provide safe, efficient and abundant electrical power for years without needing to be refueled, thereby enabling continuous operation regardless of local lighting or temperature conditions. It will support long duration surface missions, human habitation, science, payloads, and infrastructure independently of solar panels and batteries. Under the National Space Pologies set by President Donald Trump, NASA's charged with returning astronauts to the Moon, building infrastructure that will allow them to remain there, and preparing for human missions to mass and beyond. This is space time still to come, using an ice satellite to detect powerful geomagnetic storms, and later in the science report, a new study shows that high air pollution levels also cause an increase in physical disabilities. All that and more still to come on space time. This episode of space Time is brought to you by squarespace, the platform that makes building an incredible online presence not. Just possible but effortless. Squarespace gives you all the tools you need to create a professional website, claim your perfect domain, promote your brand and even get paid. All in one, easy to use place. Whether you're showing off your portfolio, selling products, or booking clients, square space has you covered. Now, let's talk about one of our listeners, Emma. She's a science communicator who started hosting small science workshops at her local community hall. But when words started to spread, she knew she needed a professional online presence, and she needed it fast, and that's why she turned to squarespace. Emma built her website in just one weekend. With Squarespace's easy tools, she listed her upcoming events and let people book tickets online. No awkward email chains, no manual payment schemes. The built in scheduling features set out automatic confirmations, and she even used square Space's email marketing to remind attendees about new events. Now, if you want to see how easy it is to bring your ideas to life online, visit squarespace dot com slash space time for a free trial, and when you're ready to launch, use the code space time at the checkout. Save ten percent on your first purchase for a website of domain. That's squaespace dot com slash space time promo code space time. And of course we have a link in our show notes the European Space Agency's Cryosat spacecraft has accurately measured the impact of recent geomagnetic storm activity from the Sun as it slammed into Earth's magnetic field. The observation show how spacecraft designed to monitor polarized sheets and floating ice can be retasked to undertake a completely different kind of mission. At the end of last year, the Cryosat mission, which had been operating for them at sixteen years, was given a remote upgrade of new software for its platform magnetometer. The magnetometer is installed on the satellite to ensure it orbits at the right attitude and directs its science instruments towards the right part of the Earth's surface. The platform magnetometers therefore an operational instrument and not designed to produce scientific data about the Earth's magnetic environment. In fact, cryosats primary mission has always been to study the Earth's ice. It carries an advanced radar instrument designed to measure small changes on the surface of ice sheets and the sea ice down to an accuracy of just a few millimeters. As part of 's Earth Explorer family of satellites, it's produced scientific databases which have provided detailed insights into Earth's polarotionans, subglacial lakes, and ice sheets. But this upgrade to its operational magnetometer means that cryosats now also able to measure changes in Earth's magnet intosphere with scientific precision, using data to calibrate its measurements from ESI's SWARM satellites, which are a dedicated magnetic field observation mission. SWARM remains ESA's primary mission to study Earth's magnetic field, or CRIOSAT maintains its focus on measuring changes in the ice sheets and the polar oceans. Still, at the beginning of. The year, CRIOSAT was able to put its newly found skills to good use when an especially strong X class solar flare crashed into Earth's atmosphere. The event, back on January eighteenth, caused some of the most intense geomagnetic storms on record, with people able to witness the studying auroral activity and much lower latitudes than usual, including sightings from its final to Sydney. The solar flare was caused by an eruption on the Sun's surface, which released huge amounts of energy that reached Earth within twenty five hours. Over a period of three days. Cryosat was able to contribute scientific data to measure the intensity of the geomagnetic storm, providing complementary data to that produced by SWARM, all very different from its originally intended mission. This report from the UK Space Agency. The Earth's ice caps are melting and growing evidence suggests that global warming is causing the sea ice in the Arctic to retreat, but the sheer size and extreme conditions of the polar regions makes it difficult for scientists to cover these areas in detail. Crios AT two, the European Space Agency's Earth Explorer mission, aims to fill these gaps both the size of the ice sheets and the thickness of the ice to the nearest centimeter. This important information will help scientists understand the impact of climate change with the UK through Professor Duncan Wingham at University College London leading Chris ATS Science Team. Christ is important because it will tell us how the changes in the Arctic are going to spread out and impact lower latitudes where most of us live. That's the object. Of the exercise. Care to orbit the North and South Poles every hour. Perhaps the simplest way of thinking about this is to imagine a ball of wool. Every time the satellite goes round the Earth, we lay down another strand on the ball, and so after about a month we have a lot of strands, and in essence we've now covered the Earth, and so we start again, and so each month we get a picture of what the ice is doing. And doing this month after month after month after month gives us a picture of what happens, for example, over a year, and then doing this year after year gives us a picture of how the ice is changing over say five years. Melting ice affects ocean circulation and this could influence our climate, so it's essential to measure the changes and ice cover accurately. Crios AT's instruments include a radar altimeter with unprecedented resolution ten times better than those on current satellites. It used the bounced echo of a signal from the sea ice and the ocean to build up a three D view of the ice. After the loss of Chriyosat one due to a launch of failure in two thousand and five, a replacement, updated satellite was immediately given the go ahead, and eads Astrium rebuilt the craft. This noisy machine is an autoclave. It's basically a giant oven, high temperature, high pressure, and it's used to bake the parts of a spacecraft so that they're bonded together and resilient enough to withstand the rigors of space and of being in orbit. And it's exactly the same process that was used to build Cryosat two. Compared to other spacecraft, however, CRYOSAT two is an unusual shape. It's not the usual boxy shape of a satellite with solar arrays sticking out to the side. In this case, we've built the solar panels on the top surfaces of the satellite that so that it can pick up power from the sun regardless of the direction that the Sun is shining on it, and that will enable it as it goes through its mission to power the instruments to make the measurements we need to make. All of criosat's data received by a ground station at Karuna in northern Sweden. The data will be processed and distributed to one hundred and fifty scientists surround the world, including Catherine Giles from the Center for Polar Observation and Modeling. Her research group is at UCL University College London. The team at University College London getting the data as soon as it's transmitted from the satellite, looking at the various processing steps this data goes through from becoming a measurement made in space to becoming a parameter that describes past our environment, whether that is the ocean height or the thickness of the ice cover. Information from criosat TOO on the Arctic and the land masses of Greenland and Antarctica give scientists fresh insight into our change in climate update current predictions that the thin crust of sea ice around the North Pole could disappear by the end of the century. And in that report from the UK Space Agency we heard from krayos AT Principal Investigator Duncan Wigham from the University College London, prayers AT Engineer Ralph Caudley from EADS Astrium, and Research fellow Catherine Giles from the University College London. This is Space Time. And Time Out Tech another brief look at some of the other stories making news in science this week. With a science report, A new study has shown that higher air pollution levels could increase the risk of physical disabilities getting worse and reduce the chances of getting better. The findings, reported in the Journal of the American Medical Association, looked at reported mobility and activity data for nearly thirty thousand over fifty year olds between the year twenty and twenty sixteen, and then compared these data with ambient measurements of pollution, nitrogen dioxide, and ozone at the participant's residential addresses preceding each survey. They found that higher concentrations of air pollution particles and nitrogen dioxide were associated with a higher risk of transitioning from no physical function limitations towards disability, and a lower chance of reverting back to healthy physical function. A new study is found that the way people swing their arms when they walk could tell you a lot about their mood. The findings, reported in the Journal of the Royal Society Open Science, found people had a better chance ability to judge someone's emotions based on videos that were shown. The authors say it seems couldn't that its swinging of the arms and legs is connected to emotion, and by manipulating the frequency of the swinging arms, they could change a subject's assessment of a person's emotions. Larger army movements were perceived to be linked with anger or reduced movements with sadness. A new survey of American teens has revealed that over half some fifty five point three percent admit that they've created at least one image using AI unification tools. The tools use artificial intelligence programs to show what a person may look like without clothing. The findings were reported in the general Plus one also showed that around a third of reported victims of these neuification tools have had their image created and shared without their consent. Well. The big news over the past week is that Google have suspended their plans for a big new data center in Australia because of the increasing cost of local electricity. But there may be a possible new light at the end of the tunnel, with plans for portable modular data centers small enough to fit inside shipping containers. The key to making them. Viable involves taking excess energy capacity generated by solar and wind supplies. That's when they're running. With the details. We're joined by technology editor Alex sahwer Roy from Ticke Advice. Start Lie Yeah. These are the first Australian data centers that pitt into a shipping container. They're made by a company called Armada currently in Europe. They will be brought to Australia and these data centers have air puttering, so no water is applied to generate answers for AI and you can have a whole bunch of computers in there with a switch that connects to the power that comes from solar and wind farms. Now, these clearly don't always work because the wind might not blow and the sun doesn't try it's rainy nighttime, and often there's so much energy produced by these renewable energy sources that it's too much for the grid and so the you know, it. Has to be powered down. So these data centers are taken to solar and wind farms, which don't always produce energy, and there's batteries that can power the data centers for days, but often there's too much energy produced and they actually have to turn the wind farms off. They have to turn the systems off so they're not sending too much energy to the grid. So there's seven point two terror whatts of energy that's wasted, and there's another ten terra watch of energy that's wasted on the grid as the power closed through the power lines to other parts. Of the country. And if there was a way of harnessing this energy and to use it to get green renewable energy AI tokens, Well that's the currency of using chat Tovt or Claude or Gemini. You need tokens. So this is a ten year mission by a gentleman who had the idea and when he saw that solar and wind farms had to be more or less temporarily turned off not to send too much energy. To the grid. And of course this is data center is a portable AI factory on the back and it can go on give me travel around the world. And so if this is a brilliant idea. And will help to bring the cost of AI down even further, because everybody wants their data center to not only do all the cloud stuff we're used to and serving up Netflix movies and powering through a WS and other services, the online orders and the online shopping and all the different things that we're used to, but also now of course AI. Then that interest in demand is only going to grow globally. So to have a portable data center is a great development, and you wonder why nobody thought of it before. That's Alexeharavroyd, Front Take Advice, Start Life, and this space Time, and that's the show for now. 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