S01E83: New Comet Intercept Mission // The Solar System's Magnetic Tunnel // Space Junk - A Warning

[00:00:00] Hi, thanks for joining me. This is Astronomy Daily. I'm your host, Andrew Dunkley. Coming up today, a Comet Intercept Mission. Nothing to do with DART or the plans of the Chinese that we talked about last week. This is another new mission. Also, the solar system has

[00:00:17] a magnetic tunnel and we look at Space Junk because it's getting so junky up there, something's going to go wrong according to one expert. That's all coming up on this edition of Astronomy Daily. And we say hello to our AI reporter, Hallie. Hi, Hallie, what's news?

[00:00:42] Oh, okay. No faffing around today, I guess. Comet strikes on Jupiter's moon Europa could help transport critical ingredients for life found on the moon's surface. To its hidden ocean of liquid water even if the impacts don't punch completely through the moon's icy shell.

[00:01:03] The discovery comes from a study led by researchers at the University of Texas at Austin, where researchers developed a computer model to observe what happens after a comet or asteroid strikes the ice shell, which is estimated to be tens of kilometers thick. The model shows

[00:01:18] that if an impact can make it at least halfway through the moon's ice shell, the heated meltwater it generates will sink through the rest of the ice, bringing oxidants, a class of chemicals required for life from the surface to the ocean,

[00:01:30] where they could help sustain any potential life in the sheltered waters. The study is comparable to the news we discussed yesterday about Saturn's ice moon and Celetus having all the ingredients for sustaining life beneath its surface.

[00:01:45] NASA conducted the first test of the newly redesigned RS-25 engine for future flights of the Space Launch System rocket, completing 209.5 seconds of a scheduled 500-second hot fire at the agency's Stennis Space Center, near Bay St. Louis, Mississippi.

[00:02:02] The hot fire test was shut down early by a non-flight system used to monitor the engine. NASA and Space Launch System lead engine contractor Araget Rocketdyne are analyzing data to review the monitoring system, evaluate engine performance, and identify the reason for the early test cutoff.

[00:02:19] Because the test was being done for redesigned engines in support of Artemis-5 and beyond, no impacts to RS-25 hardware for earlier missions is expected. The single-engine hot fire, known as a confidence test, was designed to confirm

[00:02:34] all is ready to proceed with a series of certification tests early next year on a full RS-25 certification engine. Scientists analyzed new measurements showing that the light emitted by stars outside our galaxy is 2 to 3 times brighter than the light from known

[00:02:51] populations of galaxies, challenging assumptions about the number and environment of stars are in the universe. Results of the study led by researchers at Rochester Institute of Technology have been posted to AR-14 and accepted for publication in the Astrophysical Journal.

[00:03:08] The research team analyzed hundreds of images of background light taken by the Long Range Reconnaissance Imager on NASA's New Horizons mission to calculate the cosmic optical background, the sum of light emitted by stars beyond the Milky Way over the history of

[00:03:22] the universe. If the COB brightness doesn't equal the light from galaxies we know about, it suggests there might be missing sources of optical light in the universe. And that's the news, Andrew. Thank you, Hallie. We'll catch up with you shortly. Now, we've talked about the

[00:03:39] DART mission and we've talked about a mission that China is looking at to intercept an asteroid. Well, now another agreement has been signed looking at a similar situation, but this one's a little

[00:03:51] bit different. ESA, the European Space Agency and OHB have signed a contract to move forward with the design and construction of ESA's ambitious Comet Interceptor spacecraft, which they plan to launch in 2029. Now, this is unlike other missions. Comet Interceptor's target

[00:04:09] has not been defined yet and that's because it would take too long to build a mission on the short time frame of a potential target entering the solar system for a spacecraft to reach that particular comet in time, whatever that comet would be. Instead, Comet Interceptor will

[00:04:26] be ready and unless a suitable target is identified before launch, it'll wait one and a half million kilometers behind Earth as viewed from the Sun at the gravitationally stable Lagrange Point 2. And it'll wait for a suitable comet or even an interstellar object to enter the solar system

[00:04:46] for the first time and then it'll go and check it out. Once a suitable comet or interstellar object is identified, Comet Interceptor will be deployed from its parking station and set on an intersect trajectory. The mission comprises three modules, a main spacecraft and two

[00:05:06] probes and they'll separate several days prior to the interception of the comet to perform simultaneous observations from multiple angles creating an exceptional 3D profile of the comet object or whatever it turns out to be. ESAIR is leading the development of the main spacecraft and

[00:05:25] one of the probes both carrying different but complementary instruments built by European Scientific Institutes and Industry. JAXA, the Japanese Aerospace Exploration Agency, is providing the other probe and its instruments. Comet Interceptor was originally proposed to

[00:05:44] ESAIR in July of 2018 and it was selected 11 months later. It's an example of a fast development or F-Class mission they say. Comet Interceptor is foreseen for launch as a co-passenger with ESAIR's exoplanet studying aerial spacecraft in 2029. Now the solar system is something we

[00:06:09] know quite well but then occasionally we'll hit a curveball and think well how come we didn't know that. And that's what this story is about because they've discovered a magnetic tunnel. Well they're not not so much discovered it but they are redefining what this could be because there's

[00:06:27] been a relationship between two different things that looks like they interact. A University of Toronto Astronomers Research suggests the solar system is surrounded by a magnetic tunnel that can be seen in radio waves. Jennifer West is a research associate at the Dunlap Institute for

[00:06:46] Astronomy and Astrophysics and is making a scientific case that two bright structures seen on opposite sides of the sky previously considered to be separate are actually connected and are made of rope-like filaments. The connection forms what looks like a tunnel

[00:07:03] around the solar system. Now the results of West's research have been published in the Astrophysical Journal called the North Polar Spur and the Fan Region. Astronomers have known about these two structures for decades. West says that most scientific explanations are

[00:07:21] focused on them individually and she and her colleagues by contrast believe they are the first astronomers to connect the dots or connect these two things as a single unit. Made up of charged particles and a magnetic field the structures are shaped like long ropes.

[00:07:40] They're located about 350 light years away from us and about a thousand light years in length. West has been thinking about these features on and off for about 15 years ever since she first

[00:07:52] saw a map of the radio sky. More recently she built a computer model that calculated what the radio sky would look like from Earth as she varied the shape and location of the long ropes.

[00:08:05] The model allowed West to build the structure around us and showed her what the sky would look like through our telescopes and it was that perspective that helped her match the models of the

[00:08:16] data. An expert in magnetism in galaxies in the interstellar medium West looks forward to more possible discoveries connected to this research. West says magnetic fields don't exist in isolation they all must connect to each other so the next step is to better understand how

[00:08:35] this local magnetic field connects both to the larger-scale galactic magnetic field and the smaller-scale magnetic fields around our sun and earth. In the meantime West agrees that the new tunnel model brings new insight to the scientific community. The astronomy daily podcast

[00:08:54] we've done you don't you? Now to the trouble with space junk up until a decade ago there were an average of 80 to 100 satellites per year launched into various orbits around our planet. Some re-entered Earth's atmosphere pretty quickly others remain for decades. This now seems quaint

[00:09:16] compared to what's been happening for the last five years driven largely by the rise of communication networks like SpaceX and Starlink and a whole bunch of other small satellite operators. In 2017 the United Nations Office for Outer Space Affairs said the annual number

[00:09:33] exceeded 300 by 2020 the annual number of objects launched exceeded 1000 for the first time. This year the total has already surpassed 2000 with more broadband from space networks like Amazon's Project Kuiper on the way those numbers are expected to climb. The radical

[00:09:53] increase in the number of satellites most of which are orbiting within a thousand kilometers of the surface of the earth comes as low earth orbit is becoming more and more cluttered with debris. Last month you might remember China's long March 6A rockets up a stage unexpectedly

[00:10:12] broke apart after delivering its payload into orbit there are now more than 300 pieces of trackable debris at an altitude of between 500 and 1000 kilometers. In November of 2021 Russia shot down its own Cosmos 1408 satellite creating more than a thousand fragments in orbit

[00:10:31] and they were criticized heavily for it. NASA's International Space Station has to regularly dodge this kind of debris so scientists and engineers estimate that there are hundreds of thousands of pieces of orbital debris about the size of a berry that cannot be tracked. Given

[00:10:51] their velocities and you know we're talking many times the speed of sound these small objects have the kinetic energy of a falling anvil then there are the tens of thousands of pieces of trackable debris the size of a cricket ball softball tennis ball or larger that have the

[00:11:11] kinetic energy of a large bomb while some of this debris gets dragged down into the earth's atmosphere and burns up every day humans are rapidly creating more of it so what's going to happen well nothing good according to Moriba Ja an astrodynamicist from the University of Texas at

[00:11:30] Austin Ja as an expert in the field of orbital debris and one of the foremost critics of the rising tide of space junk and he's calling for humanity to preserve low earth orbit in an

[00:11:42] interview with the ars technical website he said right now there is no coordination planning each country has plans in absence of accounting for other countries plans and that's part of the problem Ja predicts that if things keep going the way they are certain orbits will be lost

[00:12:01] due to the saturation of material around the planet and he fears there will be incidents or accidents in space if authorities don't come together on the issue the biggest problem is that the current laws only make nations countries if you like responsible for space not the private

[00:12:18] companies that are most responsible for the proliferation of material being hoisted into orbit sounds like the laws need to be changed and changed very very quickly but who's going to take responsibility for that one wonders you can find those stories on our website astronomydaily.io

[00:12:37] you can also sign up for the newsletter and get your astronomy news every day through your email inbox and don't forget to visit space nuts dot IO catch up with the latest episodes of

[00:12:50] space nuts the most recent being a q&a episode where we talk audience questions with Professor what's an astronomer at large that just about wraps us up for another day Hallie

[00:13:02] what have you got before we go I gotta run have to do some shopping shopping what's on the shopping list I'm out of coffee for starters oh really what kind of coffee do you drink Java of course

[00:13:18] very funny bye Hallie bye until next time this has been Andrew Dunkley for astronomy daily astronomy daily the podcast with your host Andrew Dunkley