From Solar Storms to Martian Canyons: The Latest in Space News
Astronomy Daily: Latest Space NewsOctober 23, 2026x
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00:24:4033.92 MB

From Solar Storms to Martian Canyons: The Latest in Space News

Show notes Last November the Sun produced its strongest radiation storm in almost twenty years, and this time scientists were ready: neutron monitors from Cornwall to Shetland, sensors on transatlantic airliners, and weather balloons launched within the hour. A new Space Weather paper shows just how patchy the storm was, with one Shetland balloon passing aviation warning thresholds while others saw nothing. Also: a marsquake proves Valles Marineris is still tectonically active, a near-synchronised binary powers the Kepler field's most violent superflares, suspected Chinese rocket debris lands in a Borneo plantation, a correction on NASA's Artemis briefing, Hera's second braking burn, and a both-hemispheres skywatch with Venus at inferior conjunction, Mercury for the south, and the Moon with Saturn. Sources · Baird et al., Space Weather (DOI) — https://doi.org/10.1029/2026SW005279 · University of Surrey release, 20 Oct 2026 — https://www.surrey.ac.uk/news/rare-solar-radiation-storm-gives-scientists-clearest-picture-yet-flight-risks · NICT — ICAO space weather centres (ACFJ) — https://swc.nict.go.jp/en/knowledge/icao.html · Song et al., Nature Communications — https://www.nature.com/articles/s41467-026-78193-6 · Columbia/phys.org — Valles Marineris — https://phys.org/news/2026-10-giant-canyon-mars-tectonically-today.html · Kővári et al., arXiv 2610.11799 — https://arxiv.org/abs/2610.11799 · Konkoly Observatory release via phys.org — https://phys.org/news/2026-10-astronomers-uncover-powerful-stellar-flares.html · AFP via phys.org — Indonesia debris — https://phys.org/news/2026-10-indonesia-probes-chinese-rocket-fragment.html · CGTN — Zhuque-2E launch 14 Oct — https://news.cgtn.com/news/2026-10-14/China-s-Zhuque-2E-rocket-launches-10-satellites-into-space-1ReYXyOhz5C/share_amp.html · ESA — Hera braking manoeuvres — https://www.esa.int/Space_Safety/Hera/Brake!_Time_for_ESA_s_Hera_asteroid_mission_to_go_slow · NASA — Artemis update advisory — https://nasa.gov/news-release/nasa-to-discuss-artemis-acceleration-status-of-upcoming-moon-missions

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This episode includes AI-generated content.


00:00:00 --> 00:00:01 Anna: Hi, everyone. Welcome back.

00:00:03 --> 00:00:06 Last November, the sun fired off a burst

00:00:06 --> 00:00:08 of particles so energetic that some of them

00:00:08 --> 00:00:10 made it all the way down to the ground.

00:00:11 --> 00:00:13 Within the hour, scientists in Britain were

00:00:13 --> 00:00:15 letting go of weather balloons.

00:00:16 --> 00:00:18 Avery: And one of those balloons rising out of

00:00:18 --> 00:00:21 Shetland flew straight into a radiation

00:00:21 --> 00:00:23 environment that crossed the international

00:00:23 --> 00:00:25 aviation warning lines.

00:00:26 --> 00:00:28 Meanwhile, a passenger jet was over the

00:00:28 --> 00:00:30 Atlantic heading for New York.

00:00:30 --> 00:00:33 Anna: Today. What a solar radiation

00:00:33 --> 00:00:36 storm actually looks like from inside the

00:00:36 --> 00:00:39 atmosphere. Plus a, uh, canyon on

00:00:39 --> 00:00:41 Mars that is still breaking, the most

00:00:41 --> 00:00:44 violent star Kepler ever watched, and a

00:00:44 --> 00:00:46 piece of rocket that landed in a palm oil

00:00:46 --> 00:00:48 plantation in Borneo.

00:00:48 --> 00:00:51 Avery: This is Astronomy daily for Thursday

00:00:51 --> 00:00:53 22nd October 2026.

00:00:54 --> 00:00:54 I'm Avery.

00:00:55 --> 00:00:57 Anna: And I'm Anna. Let's get into it.

00:00:57 --> 00:01:00 Avery: Okay, why don't you kick things off then,

00:01:00 --> 00:01:00 Anna?

00:01:00 --> 00:01:03 Anna: On the 11th of November last year, at

00:01:03 --> 00:01:06 about 20 past 10 in the morning UTC,

00:01:06 --> 00:01:09 the sun produced what's called a ground level

00:01:09 --> 00:01:12 enhancement. It's the 77th ever

00:01:12 --> 00:01:14 recorded, so it goes by

00:01:14 --> 00:01:17 gle77 and it was the

00:01:17 --> 00:01:19 largest in almost 20 years.

00:01:20 --> 00:01:23 Avery: Lets unpack the name because it's doing a lot

00:01:23 --> 00:01:25 of work most of the time. Particles

00:01:25 --> 00:01:28 from the sun hit the top of the atmosphere

00:01:28 --> 00:01:30 and, um, that's the end of them. Um, they

00:01:30 --> 00:01:32 collide with air molecules high up and their

00:01:32 --> 00:01:34 energy gets spread out and absorbed.

00:01:35 --> 00:01:37 Anna: But occasionally a solar eruption

00:01:37 --> 00:01:40 accelerates protons to such high energies

00:01:40 --> 00:01:43 that they smash into the upper atmosphere and

00:01:43 --> 00:01:45 set off a cascade, a shower of

00:01:45 --> 00:01:48 secondary particles, including neutrons, that

00:01:48 --> 00:01:50 reaches all the way down to the surface.

00:01:51 --> 00:01:53 Instruments on the ground called neutron

00:01:53 --> 00:01:56 monitors see the count jump. That's

00:01:56 --> 00:01:59 a ground level enhancement. They're rare.

00:01:59 --> 00:02:02 77 of them since the records began in the

00:02:02 --> 00:02:02 1940s.

00:02:03 --> 00:02:06 Avery: And this one came off the back of an X5

00:02:06 --> 00:02:09 class solar flare during the busiest stretch

00:02:09 --> 00:02:10 of the current solar cycle.

00:02:11 --> 00:02:13 Anna: A paper published on Tuesday in the journal

00:02:13 --> 00:02:16 Space Weather pulls together what the authors

00:02:16 --> 00:02:19 describe as the most comprehensive set of

00:02:19 --> 00:02:21 measurements ever made through the atmosphere

00:02:21 --> 00:02:24 during one of these events. It's led by

00:02:24 --> 00:02:27 Fraser Baird and Ben Cluer at the University

00:02:27 --> 00:02:30 of Surrey with the UK Met Office and the

00:02:30 --> 00:02:32 Royal Netherlands Meteorological Institute.

00:02:33 --> 00:02:36 Avery: Three kinds of instrument all running at

00:02:36 --> 00:02:39 once. First, a, uh, network of

00:02:39 --> 00:02:41 neutron monitors on the ground stretching

00:02:41 --> 00:02:44 from Cornwall in the far southwest of England

00:02:45 --> 00:02:48 all the way up to Shetland. The

00:02:48 --> 00:02:50 authors point out that a decade ago the UK

00:02:50 --> 00:02:53 had no operational sensors like this at all.

00:02:54 --> 00:02:57 Anna: Second, radiation monitors on

00:02:57 --> 00:02:59 commercial passenger jets flying out of

00:02:59 --> 00:03:02 Heathrow. And third, radiation

00:03:02 --> 00:03:04 monitors carried up on weather balloons, the

00:03:04 --> 00:03:06 same kind of balloons the Met Office launches

00:03:06 --> 00:03:09 every day for forecasting rising to more

00:03:09 --> 00:03:11 than 30 kilometres.

00:03:11 --> 00:03:14 Avery: And the balloons were ready when the

00:03:14 --> 00:03:16 alerts came in from neutron monitors around

00:03:16 --> 00:03:19 the world. The launches were triggered within

00:03:19 --> 00:03:19 the hour.

00:03:20 --> 00:03:22 Anna: The headline is how uneven it was

00:03:23 --> 00:03:26 on the ground. The neutron monitors saw a

00:03:26 --> 00:03:28 big early peak in the north and a

00:03:28 --> 00:03:31 smaller peak in the south about an hour

00:03:31 --> 00:03:33 later. Same storm, same small

00:03:33 --> 00:03:35 country, different experience.

00:03:36 --> 00:03:39 Avery: Up high, the contrast was even sharper.

00:03:39 --> 00:03:42 The balloon from Lerwick and Shetland went

00:03:42 --> 00:03:44 through levels above the International Civil

00:03:44 --> 00:03:47 Aviation Organisation's moderate advisory

00:03:47 --> 00:03:49 threshold. At, uh, business jet cruising

00:03:49 --> 00:03:52 heights several hours after the storm peaked,

00:03:53 --> 00:03:55 and higher still at the altitudes where

00:03:55 --> 00:03:58 supersonic aircraft fly, it measured twice

00:03:58 --> 00:03:59 the severe threshold.

00:04:00 --> 00:04:03 Anna: Meanwhile, balloons launched from Camborn and

00:04:03 --> 00:04:05 Cornwall and from the Netherlands saw

00:04:05 --> 00:04:07 no significant rise at all.

00:04:08 --> 00:04:11 Avery: Then the aircraft Heathrow to New

00:04:11 --> 00:04:13 York JFK flight that departed at quarter to

00:04:13 --> 00:04:15 12 UTC, right in the thick of it,

00:04:16 --> 00:04:19 recorded a rise in total radiation dose of

00:04:19 --> 00:04:22 42.6% over normal background.

00:04:22 --> 00:04:25 That's a big jump. But it did not cross any

00:04:25 --> 00:04:27 of the international warning thresholds.

00:04:27 --> 00:04:30 Anna: And a Heathrow to Newark flight that left six

00:04:30 --> 00:04:33 hours later saw no significant increase

00:04:33 --> 00:04:34 at all.

00:04:34 --> 00:04:37 Avery: A quick note from us on that may

00:04:37 --> 00:04:40 see 46% quoted in coverage, which

00:04:40 --> 00:04:42 is the figure in the university's press

00:04:42 --> 00:04:44 release. The paper itself says

00:04:44 --> 00:04:47 42.6 and that's the one we're

00:04:47 --> 00:04:48 using.

00:04:48 --> 00:04:51 Anna: So why would Shetland and Cornwall,

00:04:51 --> 00:04:54 1 kilometres apart, have such

00:04:54 --> 00:04:55 different days?

00:04:56 --> 00:04:59 Avery: It comes down to Earth's magnetic field near

00:04:59 --> 00:05:01 the equator. The field lines run roughly

00:05:01 --> 00:05:04 parallel to the ground, so an incoming

00:05:04 --> 00:05:07 charged particle has to cross them and only

00:05:07 --> 00:05:09 the most energetic ones make it through

00:05:09 --> 00:05:10 toward the poles.

00:05:10 --> 00:05:13 The field lines dip down into the Earth and

00:05:13 --> 00:05:15 particles can spiral in along them much more

00:05:15 --> 00:05:18 easily. Physicists call the threshold a, uh,

00:05:18 --> 00:05:21 cutoff. And it falls the further you go

00:05:21 --> 00:05:22 towards the poles.

00:05:23 --> 00:05:25 Anna: So every step north lowers the bar.

00:05:26 --> 00:05:29 Shetland at 60 degrees north lets in

00:05:29 --> 00:05:31 particles that Cornwall at 50, keeps out.

00:05:32 --> 00:05:34 That's why polar flight routes are the most

00:05:34 --> 00:05:37 exposed and why a, uh, strong storm can

00:05:37 --> 00:05:40 push the exposed zone further from the poles.

00:05:40 --> 00:05:42 Avery: And the timing differences tell you the

00:05:42 --> 00:05:45 particles didn't arrive as one smooth wave.

00:05:46 --> 00:05:48 They came in from a preferred direction,

00:05:49 --> 00:05:50 which is why the authors describe the event

00:05:51 --> 00:05:53 as strongly anisotropic.

00:05:53 --> 00:05:55 Anna: Here's the part that I think is the real

00:05:55 --> 00:05:58 story. The current international advisory

00:05:58 --> 00:06:00 system run through ICAO

00:06:01 --> 00:06:04 relies mostly on models informed

00:06:04 --> 00:06:06 by measurements on the ground and in space.

00:06:07 --> 00:06:09 And during GLE 77,

00:06:09 --> 00:06:12 no ICAO advisory was issued at

00:06:12 --> 00:06:13 all.

00:06:13 --> 00:06:16 Avery: Yet one balloon was sitting well above

00:06:16 --> 00:06:18 the moderate line. And at

00:06:18 --> 00:06:21 supersonic altitudes above the severe line,

00:06:22 --> 00:06:24 the Author's argument is that direct

00:06:24 --> 00:06:26 measurements through the atmosphere need to

00:06:26 --> 00:06:29 be part of the system because these events

00:06:29 --> 00:06:32 are so patchy that a model tuned to the

00:06:32 --> 00:06:34 average can miss what's happening over one

00:06:34 --> 00:06:35 corner of the map.

00:06:35 --> 00:06:38 Anna: Krista Hammond, space weather manager at the

00:06:38 --> 00:06:41 Met Office and a co author, described

00:06:41 --> 00:06:44 it as the first time radiation data had

00:06:44 --> 00:06:46 been collected through the atmosphere during

00:06:46 --> 00:06:48 a, uh, space weather event. In this way.

00:06:49 --> 00:06:51 Avery: And it isn't only about people.

00:06:51 --> 00:06:54 Aircraft now rely on sensitive electronics

00:06:55 --> 00:06:57 and energetic particles can flip bits in a

00:06:57 --> 00:07:00 computer. Airbus recalled around

00:07:00 --> 00:07:03 6 A320 family jets for a

00:07:03 --> 00:07:06 software fix late last year after an incident

00:07:06 --> 00:07:09 blamed on cosmic radiation. To be

00:07:09 --> 00:07:11 clear, that one wasn't during a solar storm.

00:07:11 --> 00:07:14 It was a single stray particle. But it's

00:07:14 --> 00:07:17 the same kind of particle that storms deliver

00:07:17 --> 00:07:19 in bulk now, some

00:07:19 --> 00:07:22 Anna: proportion, because this is the kind of story

00:07:22 --> 00:07:24 that can sound scarier than it is.

00:07:25 --> 00:07:28 Back in episode 193, we said

00:07:28 --> 00:07:31 a long haul flight gives you a dose roughly

00:07:31 --> 00:07:34 comparable to a chest x Ray. A 40%

00:07:34 --> 00:07:36 rise on top of that is a 40%

00:07:36 --> 00:07:39 rise on a small number. For an

00:07:39 --> 00:07:41 occasional passenger, it's not a health

00:07:41 --> 00:07:41 worry.

00:07:42 --> 00:07:45 Avery: Where it matters is for crews who fly

00:07:45 --> 00:07:47 hundreds of hours a year and for planning at

00:07:47 --> 00:07:50 the margins when to reroute, when to fly

00:07:50 --> 00:07:53 a bit lower, when it's worth holding a flight

00:07:53 --> 00:07:56 on the ground. That's what the thresholds are

00:07:56 --> 00:07:56 for.

00:07:57 --> 00:07:59 Anna: And it's one event measured

00:07:59 --> 00:08:02 over one country. The authors aren't

00:08:02 --> 00:08:05 claiming a rule for every storm, they're

00:08:05 --> 00:08:07 showing how much the picture changes when you

00:08:07 --> 00:08:08 actually go up and measure it.

00:08:09 --> 00:08:12 Avery: There's no Australian team on this paper, so

00:08:12 --> 00:08:13 let's be straight about that.

00:08:13 --> 00:08:15 But there is a direct line to us.

00:08:16 --> 00:08:19 ICAO's global space weather advisories come

00:08:19 --> 00:08:21 from four centres and one of them is a

00:08:21 --> 00:08:24 consortium of Australia, Canada, France and

00:08:24 --> 00:08:27 Japan. Within it, our own Bureau of

00:08:27 --> 00:08:30 Meteorology and Meteo France are the ones who

00:08:30 --> 00:08:32 issue the advisories. That service started in

00:08:32 --> 00:08:33 November 2019.

00:08:34 --> 00:08:37 Anna: So the question this paper raises, whether

00:08:37 --> 00:08:39 advisories should lean more on direct

00:08:39 --> 00:08:42 measurement, lands on desks in Australia

00:08:42 --> 00:08:43 too.

00:08:43 --> 00:08:45 And the physics doesn't care which hemisphere

00:08:45 --> 00:08:48 you're in. Routes between Australia

00:08:48 --> 00:08:51 and South America run far south towards

00:08:51 --> 00:08:53 Antarctica, which is exactly where the

00:08:53 --> 00:08:55 magnetic shield is thinnest.

00:08:55 --> 00:08:58 Avery: If you've been with us a while, this sits on

00:08:58 --> 00:09:00 a familiar dial. In episode

00:09:00 --> 00:09:03 192 it was the potential for

00:09:03 --> 00:09:05 a superflare. In 193,

00:09:06 --> 00:09:08 aviation dose running higher at solar

00:09:08 --> 00:09:11 minimum. And in 196, in the same

00:09:11 --> 00:09:14 journal, the 1848 telegraph storm

00:09:14 --> 00:09:17 in Exeter today. It's what the

00:09:17 --> 00:09:19 strongest event of the cycle so far actually

00:09:19 --> 00:09:21 did to the sky over Britain.

00:09:22 --> 00:09:24 Anna: Balloons into the storm.

00:09:24 --> 00:09:27 Sometimes the best instrument is the one you

00:09:27 --> 00:09:29 can launch in an hour from

00:09:29 --> 00:09:31 Avery: Earth's sky to the far side of

00:09:31 --> 00:09:32 Mars.

00:09:32 --> 00:09:35 Valles Marineris is the largest canyon

00:09:35 --> 00:09:37 system in the solar system, about

00:09:37 --> 00:09:40 3 kilometres long, up

00:09:40 --> 00:09:43 to 600 wide and more than nine

00:09:43 --> 00:09:46 kilometres deep. Lay it across Australia

00:09:46 --> 00:09:49 and it would run from Perth to past Brisbane.

00:09:49 --> 00:09:52 Anna: And it formed billions of years ago.

00:09:53 --> 00:09:55 The question has always been whether

00:09:55 --> 00:09:58 it's a fossil or whether it's

00:09:58 --> 00:09:59 still moving.

00:09:59 --> 00:10:02 Avery: A paper published last Thursday in Nature

00:10:02 --> 00:10:05 Communications says it's still moving.

00:10:05 --> 00:10:08 Jung Hoon Sung and Do Yeon Kim at

00:10:08 --> 00:10:11 Imperial College London with Folarin Kolawole

00:10:11 --> 00:10:14 at Columbia University went back to a single

00:10:14 --> 00:10:16 Marsquake recorded by NASA's InSight

00:10:16 --> 00:10:18 lander, known as

00:10:18 --> 00:10:20 S0976A.

00:10:20 --> 00:10:22 Anna: That's SOL

00:10:22 --> 00:10:25 976, 25-8-2021.

00:10:26 --> 00:10:29 And it was special. It came from

00:10:29 --> 00:10:31 the far side of Mars, from the lander,

00:10:32 --> 00:10:35 and it's the only Marsquake Insight ever

00:10:35 --> 00:10:37 located in the planet's western hemisphere.

00:10:38 --> 00:10:40 Avery: Insight, huh? Had one seismometer, which

00:10:40 --> 00:10:43 makes this hard with one station. You can't

00:10:43 --> 00:10:46 triangulate in the usual way, but by

00:10:46 --> 00:10:49 modelling the shapes and strengths of the

00:10:49 --> 00:10:51 waves that bounced off the Martian surface on

00:10:51 --> 00:10:53 their way to the lander, the team

00:10:53 --> 00:10:55 reconstructed what happened at the source.

00:10:56 --> 00:10:59 Anna: The answer? A, uh, strike slip fault

00:10:59 --> 00:11:02 where two blocks of crust slide sideways past

00:11:02 --> 00:11:05 each other about 20 to 40 kilometres

00:11:05 --> 00:11:07 down beneath the western end of the canyon

00:11:07 --> 00:11:10 near East Chasma, a magnitude

00:11:10 --> 00:11:12 around three and a half.

00:11:12 --> 00:11:14 Avery: They tested the alternatives.

00:11:15 --> 00:11:17 Meteoroid impact or a, ah, landslide.

00:11:17 --> 00:11:20 Just can't reproduce the waves. And a

00:11:20 --> 00:11:22 landslide big enough would have needed at

00:11:22 --> 00:11:25 least 10 million cubic metres of rock

00:11:25 --> 00:11:28 and left a fresh scar hundreds of metres to a

00:11:28 --> 00:11:31 kilometre across. Orbital images taken

00:11:31 --> 00:11:33 afterwards covering about half the likely

00:11:33 --> 00:11:36 source area show nothing like it.

00:11:36 --> 00:11:39 Anna: So what's pushing on it? The

00:11:39 --> 00:11:42 authors point to a combination the whole

00:11:42 --> 00:11:45 planet slowly cooling and contracting,

00:11:46 --> 00:11:48 the enormous weight of the Tharsis volcanic

00:11:48 --> 00:11:51 region next door and the canyon

00:11:51 --> 00:11:54 itself, where so much rock has been eroded

00:11:54 --> 00:11:57 away that the crust has been unloaded.

00:11:57 --> 00:12:00 Faults made billions of years ago are still

00:12:00 --> 00:12:03 weak enough to slip under today's stresses.

00:12:04 --> 00:12:06 Avery: Now there's a lovely Australian footnote

00:12:06 --> 00:12:09 here. To prove the single seismometer method

00:12:09 --> 00:12:12 works, the team tested it on a magnitude

00:12:12 --> 00:12:14 6.5 earthquake in Nevada in 2020

00:12:15 --> 00:12:17 recorded at, ah, just one station on the

00:12:17 --> 00:12:19 other side of the world. The global Seismic

00:12:19 --> 00:12:21 Network Station in Canberra.

00:12:21 --> 00:12:23 The method recovered the right kind of fault

00:12:23 --> 00:12:25 and the right depth.

00:12:25 --> 00:12:28 Anna: A disclosure the data are from

00:12:28 --> 00:12:31 2021 and insight stopped working

00:12:31 --> 00:12:34 in 2022. So this is a new

00:12:34 --> 00:12:36 analysis of an old recording

00:12:37 --> 00:12:40 and it's one quake located with a

00:12:40 --> 00:12:42 single instrument. No aftershocks were

00:12:42 --> 00:12:45 recorded, but the team calculates

00:12:45 --> 00:12:48 INSIGHT had only about a, uh, one in a

00:12:48 --> 00:12:49 thousand chance of catching one.

00:12:49 --> 00:12:52 Avery: From that, it also fits a pattern

00:12:52 --> 00:12:53 we've been following.

00:12:54 --> 00:12:56 On Tuesday in episode 209,

00:12:57 --> 00:12:59 it was the Moon still shrinking and

00:12:59 --> 00:13:02 cracking. Mars now joins it.

00:13:03 --> 00:13:05 Worlds without plate tectonics still have

00:13:05 --> 00:13:07 faults, and the old ones keep doing the

00:13:07 --> 00:13:10 Anna: work from quakes to flares.

00:13:11 --> 00:13:13 While we're on the subject of things that

00:13:13 --> 00:13:16 erupt, NASA's Kepler telescope

00:13:16 --> 00:13:18 watched about 150

00:13:18 --> 00:13:20 stars for four years.

00:13:20 --> 00:13:23 And of all of them, the one that produced the

00:13:23 --> 00:13:25 most energetic flares was a red giant

00:13:25 --> 00:13:26 called KIC

00:13:27 --> 00:13:29 2852961.

00:13:30 --> 00:13:33 Avery: Not the biggest star, not the brightest,

00:13:33 --> 00:13:36 just by a wide margin, the

00:13:36 --> 00:13:37 most violent.

00:13:38 --> 00:13:41 Anna: A team at the Konkoly Observatory in

00:13:41 --> 00:13:43 Budapest led by Zolt Kovari

00:13:44 --> 00:13:46 already showed back in 2020 that its

00:13:46 --> 00:13:49 superflares were follow the same physics as

00:13:49 --> 00:13:51 flares on very different kinds of stars.

00:13:52 --> 00:13:55 Now they've worked out what powers it, and

00:13:55 --> 00:13:57 the answer involves a partner.

00:13:57 --> 00:14:00 Avery: With new radial velocity measurements.

00:14:00 --> 00:14:02 They confirm the giant is in a close binary

00:14:02 --> 00:14:05 with a faint dwarf companion. When the

00:14:05 --> 00:14:08 giant swelled up to its current size, about

00:14:08 --> 00:14:10 12 times the radius of the sun, the tidal

00:14:10 --> 00:14:13 pull between the two became enormously

00:14:13 --> 00:14:16 stronger. The effect scales with the

00:14:16 --> 00:14:18 eighth power of the ratio of their separation

00:14:18 --> 00:14:21 to the star size. So swelling up

00:14:21 --> 00:14:22 changes everything.

00:14:23 --> 00:14:25 Anna: Those tides have been forcing the giant to

00:14:25 --> 00:14:28 spin in step with its orbit and the

00:14:28 --> 00:14:30 orbit to become circular. And it's

00:14:30 --> 00:14:33 nearly there. Nearly, but not

00:14:33 --> 00:14:34 quite.

00:14:34 --> 00:14:37 Avery: That not quite is the key because

00:14:37 --> 00:14:40 it isn't fully locked. Different latitudes of

00:14:40 --> 00:14:43 the star still rotate at slightly different

00:14:43 --> 00:14:45 speeds. That differential rotation

00:14:45 --> 00:14:48 drives a magnetic dynamo, builds

00:14:48 --> 00:14:50 enormous star spots that store magnetic

00:14:50 --> 00:14:53 energy and twists the field lines above them

00:14:53 --> 00:14:54 until they snap.

00:14:55 --> 00:14:56 That's a super flare.

00:14:57 --> 00:14:59 Anna: And the companion isn't pulling the trigger

00:14:59 --> 00:15:02 directly. The team looked for flares bunching

00:15:02 --> 00:15:05 at particular points in the orbit and found

00:15:05 --> 00:15:07 none. The companion built the

00:15:07 --> 00:15:10 engine. The giant holds the

00:15:10 --> 00:15:11 ignition key.

00:15:11 --> 00:15:14 Avery: A disclosure this is a, uh, preprint from

00:15:14 --> 00:15:17 earlier this month. The observatory says it's

00:15:17 --> 00:15:19 been accepted by Astronomy and Astrophysics,

00:15:19 --> 00:15:22 but the journal version isn't out yet. And

00:15:22 --> 00:15:25 for our southern listeners, the Kepler field

00:15:25 --> 00:15:28 is in Cygnus and Lyra northern patch of

00:15:28 --> 00:15:28 sky.

00:15:28 --> 00:15:31 Anna: But it pairs nicely with our lead.

00:15:32 --> 00:15:34 That was a flare on our own star, measured

00:15:34 --> 00:15:36 from inside our atmosphere.

00:15:37 --> 00:15:39 This is the same magnetic physics

00:15:40 --> 00:15:43 turned up much, much further on someone

00:15:43 --> 00:15:43 else's.

00:15:44 --> 00:15:47 Avery: Closer to home now. Very close, actually.

00:15:48 --> 00:15:50 On Sunday evening, residents near the town of

00:15:50 --> 00:15:53 Sampit in central Kalimantan,

00:15:53 --> 00:15:56 Indonesian Borneo, heard a loud bang.

00:15:57 --> 00:15:59 Anna: On Monday morning, A plantation worker

00:15:59 --> 00:16:02 named Wardy Tamroni found a large

00:16:02 --> 00:16:05 metal object in a palm oil plantation

00:16:06 --> 00:16:08 about three kilometres from the company

00:16:08 --> 00:16:10 housing where he and his colleagues live.

00:16:11 --> 00:16:14 Local police described it as an aluminium

00:16:14 --> 00:16:16 plate, up to nine metres long,

00:16:16 --> 00:16:19 irregular in shape, with burn marks.

00:16:19 --> 00:16:22 Avery: On Tuesday, a second rounder piece

00:16:22 --> 00:16:25 turned up about a kilometre away. Both

00:16:25 --> 00:16:28 are being examined at a nearby military air

00:16:28 --> 00:16:30 base. Indonesia's Civil Aviation

00:16:30 --> 00:16:33 Authority says nobody was hurt, nothing was

00:16:33 --> 00:16:36 damaged and there's no radiation or

00:16:36 --> 00:16:37 toxicity risk.

00:16:37 --> 00:16:40 Anna: Mr. Tamroni said the workers had already

00:16:40 --> 00:16:43 gone home for the day, so nobody was in that

00:16:43 --> 00:16:45 part of the plantation when it came down.

00:16:45 --> 00:16:48 Avery: Indonesia's National Research and Innovation

00:16:48 --> 00:16:51 agency, Brin M says the

00:16:51 --> 00:16:53 debris appears to come From a Chinese

00:16:53 --> 00:16:55 Zui2e rocket, a, uh,

00:16:55 --> 00:16:58 Zuwei2e launched on the 14th of October

00:16:58 --> 00:17:01 from northwest China, carrying 10 satellites.

00:17:02 --> 00:17:04 Anna: That attribution is preliminary and we'll

00:17:04 --> 00:17:07 treat it that way. China's space agency

00:17:07 --> 00:17:10 couldn't be reached for comment and nobody

00:17:10 --> 00:17:12 has said yet which part of the rocket this

00:17:12 --> 00:17:12 might be.

00:17:13 --> 00:17:16 Avery: Brin researcher Thomas Jamaluddin

00:17:16 --> 00:17:18 made the general point not, um, everything

00:17:18 --> 00:17:21 burns up on RE entry and, um, the more heat

00:17:21 --> 00:17:23 resistant parts can survive to the ground.

00:17:24 --> 00:17:25 Most of it lands in the ocean.

00:17:25 --> 00:17:28 Simply because most of the planet is ocean.

00:17:29 --> 00:17:31 Anna: The odds of any one person being hit

00:17:31 --> 00:17:34 are still tiny, lower than being struck

00:17:34 --> 00:17:37 by lightning, according to the European Space

00:17:37 --> 00:17:39 agency. But ESA's

00:17:39 --> 00:17:42 own space debris Office says RE entry risk

00:17:42 --> 00:17:45 grew considerably between 2019 and

00:17:45 --> 00:17:48 2024 simply because so

00:17:48 --> 00:17:48 much more

00:17:48 --> 00:17:51 Avery: is being launched and this region has

00:17:51 --> 00:17:54 history. In 1979, pieces of the

00:17:54 --> 00:17:56 Skylab space station came down around

00:17:56 --> 00:17:58 Esperance in Western Australia.

00:17:59 --> 00:18:01 Today's story is a reminder that uncontrolled

00:18:01 --> 00:18:04 RE entries still happen and that the people

00:18:04 --> 00:18:06 underneath usually get no warning at all.

00:18:07 --> 00:18:08 We're also still waiting on the RE entry of

00:18:08 --> 00:18:11 NASA Swift Observatory, which NASA hasn't yet

00:18:11 --> 00:18:12 given a date for.

00:18:13 --> 00:18:16 Anna: First, a, uh, correction. On Wednesday's

00:18:16 --> 00:18:18 episode, we said NASA's Artemis update

00:18:18 --> 00:18:21 was Thursday at 2pm Eastern.

00:18:21 --> 00:18:24 The time was right, but the day was wrong.

00:18:24 --> 00:18:27 It's Friday the 23rd at 2pm

00:18:27 --> 00:18:30 Eastern. That's 11am on the U.S.

00:18:30 --> 00:18:32 west Coast, 7pm in London and

00:18:33 --> 00:18:35 5am Saturday here in Sydney.

00:18:36 --> 00:18:38 Our apologies. We'll bring you what NASA says

00:18:38 --> 00:18:39 in

00:18:39 --> 00:18:41 Avery: the weekend wrap and ESA's Hara

00:18:41 --> 00:18:44 spacecraft was due to fire its thrusters

00:18:44 --> 00:18:46 again early this morning European time.

00:18:47 --> 00:18:49 This is its second braking burn, about 31

00:18:49 --> 00:18:52 minutes long following the 93 minute burn

00:18:52 --> 00:18:55 last week. It's meant to deliver most of

00:18:55 --> 00:18:57 the remaining slowdown. HERA needs to match

00:18:57 --> 00:19:00 the speed of the Didymos asteroid pair and

00:19:00 --> 00:19:02 correct for any shortfall from the first.

00:19:03 --> 00:19:05 Anna: ESA confirmed last week's burn the following

00:19:05 --> 00:19:08 day, so we expect word on this one

00:19:08 --> 00:19:11 shortly after that. Three

00:19:11 --> 00:19:13 smaller manoeuvres later this month should

00:19:13 --> 00:19:16 bring Hera's speed relative to the asteroids

00:19:16 --> 00:19:19 to down to almost zero ahead of arrival

00:19:19 --> 00:19:21 in November at the scene of NASA's DART

00:19:21 --> 00:19:22 impact.

00:19:23 --> 00:19:25 Avery: Time to look up and this week both

00:19:25 --> 00:19:28 hemispheres get something, though not the

00:19:28 --> 00:19:28 same thing.

00:19:29 --> 00:19:31 Anna: First Venus. It reaches

00:19:31 --> 00:19:34 inferior conjunction on Saturday, passing

00:19:34 --> 00:19:37 between Earth and the Sun. The moment

00:19:37 --> 00:19:40 falls at about 2 in the afternoon UTC on

00:19:40 --> 00:19:42 Saturday. 10 in the morning in New York,

00:19:43 --> 00:19:46 7 in Los Angeles, 23 in the afternoon in

00:19:46 --> 00:19:48 London and around 1 o' clock early on

00:19:48 --> 00:19:50 Sunday morning in Sydney.

00:19:50 --> 00:19:53 Avery: At that point it's only about six and a half

00:19:53 --> 00:19:56 degrees from the Sun. Its disc is huge,

00:19:56 --> 00:19:59 more than a minute of arc across. But the

00:19:59 --> 00:20:01 lit side faces away from us and um, the

00:20:01 --> 00:20:04 glare makes it effectively invisible.

00:20:04 --> 00:20:07 Anna: So please don't go hunting for it. Never

00:20:07 --> 00:20:10 point binoculars or a telescope anywhere near

00:20:10 --> 00:20:10 the Sun.

00:20:11 --> 00:20:13 Looking at the sun itself, even briefly,

00:20:13 --> 00:20:16 needs a proper solar filter that meets the

00:20:16 --> 00:20:18 international standard ISO

00:20:18 --> 00:20:21 123122. And

00:20:21 --> 00:20:24 sunglasses are not enough. Venus

00:20:24 --> 00:20:26 will reappear in the morning sky in a couple

00:20:26 --> 00:20:28 of weeks and it's worth the wait.

00:20:29 --> 00:20:31 Avery: Mercury, on the other hand, is a gift to

00:20:31 --> 00:20:34 the south this week from Sydney Tonight

00:20:34 --> 00:20:37 it's about 21 degrees above the western

00:20:37 --> 00:20:40 horizon at sunset and it stays up well into

00:20:40 --> 00:20:40 dusk.

00:20:41 --> 00:20:44 Anna: Compare that with about eight and a half

00:20:44 --> 00:20:47 degrees from Los Angeles, six from New

00:20:47 --> 00:20:49 York and barely two from

00:20:49 --> 00:20:50 London.

00:20:50 --> 00:20:53 It's the same spring evening geometry

00:20:53 --> 00:20:56 we've talked about before. The line of the

00:20:56 --> 00:20:59 planets stands up steeply from the southern

00:20:59 --> 00:21:02 horizon at dusk this time of year and

00:21:02 --> 00:21:04 lies flat in the north.

00:21:04 --> 00:21:07 Avery: Mercury is fading though from about magnitude

00:21:07 --> 00:21:10 half now to past magnitude two by the end of

00:21:10 --> 00:21:13 the month. So southern viewers, this

00:21:13 --> 00:21:14 weekend is your window.

00:21:15 --> 00:21:17 Anna: Everyone gets this one on Saturday

00:21:17 --> 00:21:18 evening.

00:21:18 --> 00:21:21 The waxing gibbous moon sits near Saturn

00:21:21 --> 00:21:24 from Sydney at ah, dusk around 20

00:21:24 --> 00:21:27 to 8. Both are about 27

00:21:27 --> 00:21:29 degrees up, roughly six and a half degrees.

00:21:29 --> 00:21:32 Avery: Apart from Los Angeles and New York, they're

00:21:32 --> 00:21:35 lower around 15 degrees up at dusk,

00:21:35 --> 00:21:38 about 8 to 10 degrees apart and

00:21:38 --> 00:21:41 from London, about 6 degrees apart but

00:21:41 --> 00:21:43 low, with Saturn under 10 degrees.

00:21:43 --> 00:21:46 So find a clear horizon to the southeast.

00:21:46 --> 00:21:49 Anna: The Moon is full on Monday at 11 minutes

00:21:49 --> 00:21:52 past 4 UTC. That's quarter past

00:21:52 --> 00:21:55 three Monday afternoon in Sydney. So Sunday

00:21:55 --> 00:21:57 night is your best look. Here in the

00:21:57 --> 00:22:00 Americas, it falls on Sunday evening.

00:22:00 --> 00:22:02 In the north, it's the hunter's moon.

00:22:03 --> 00:22:05 Avery: And, um, a clock note for our northern

00:22:05 --> 00:22:05 listeners.

00:22:06 --> 00:22:08 The UK and um, Europe fall back an hour this

00:22:08 --> 00:22:11 Sunday the 25th. The United States

00:22:11 --> 00:22:13 follows on the 1st of November.

00:22:13 --> 00:22:16 Anna: Now the North's turn. Before dawn,

00:22:16 --> 00:22:19 Mars and Jupiter are drawing together in the

00:22:19 --> 00:22:22 eastern sky. They're about nine and a

00:22:22 --> 00:22:25 half degrees apart now four and a quarter

00:22:25 --> 00:22:27 by the 5th of November, and closest

00:22:27 --> 00:22:30 at about one and a quarter degrees around

00:22:30 --> 00:22:33 Avery: the 15th from Los Angeles and New York.

00:22:33 --> 00:22:36 At first light, Mars is around 60

00:22:36 --> 00:22:39 degrees up and Jupiter around 55.

00:22:39 --> 00:22:42 London gets them at about 50 and 45.

00:22:43 --> 00:22:46 From Sydney, they're lower, about 25

00:22:46 --> 00:22:49 and 22. So Southern watchers

00:22:49 --> 00:22:51 need a clear eastern view.

00:22:52 --> 00:22:54 Anna: And while you're out before dawn, the tail of

00:22:54 --> 00:22:57 the Orionid meteor shower is still running.

00:22:57 --> 00:23:00 The radiant just above the red star

00:23:00 --> 00:23:02 Betelgeuse is about 40 degrees up from

00:23:02 --> 00:23:05 Sydney before dawn and higher 50

00:23:05 --> 00:23:08 to 65 degrees from the northern cities.

00:23:08 --> 00:23:11 Rates are past their peak and the bright moon

00:23:11 --> 00:23:14 sets late, so the hour before dawn is

00:23:14 --> 00:23:14 best.

00:23:15 --> 00:23:18 Avery: So the south gets Mercury and

00:23:18 --> 00:23:21 a high moon and Saturn. The north

00:23:21 --> 00:23:24 gets the planets before dawn and the

00:23:24 --> 00:23:27 higher meteor radiant, Fair Trade.

00:23:27 --> 00:23:29 Anna: That's the show today.

00:23:30 --> 00:23:32 Weather balloons that flew into the biggest

00:23:32 --> 00:23:35 solar radiation storm in almost 20 years.

00:23:36 --> 00:23:38 A Martian canyon that's still breaking.

00:23:39 --> 00:23:41 The companion star that built a superflare

00:23:41 --> 00:23:44 engine and rocket debris in a

00:23:44 --> 00:23:45 Borneo plantation.

00:23:46 --> 00:23:47 Avery: Show notes and sources

00:23:47 --> 00:23:50 are@astronomydaily.IO

00:23:50 --> 00:23:52 and if you've got a question you'd like us to

00:23:52 --> 00:23:54 chase, the contact form is on the site.

00:23:55 --> 00:23:57 Some of our best segments have started there.

00:23:57 --> 00:24:00 Anna: Tomorrow we'll have word on Hera's second

00:24:00 --> 00:24:03 burn and on Saturday, the weekend wrap,

00:24:03 --> 00:24:05 including whatever NASA says about Artemis.

00:24:06 --> 00:24:07 Avery: I'm Avery.

00:24:07 --> 00:24:10 Anna: And I'm Anna. From all of us at ah,

00:24:10 --> 00:24:12 Astronomy AstroDailyPod and the bytes.com

00:24:12 --> 00:24:15 podcast network, clear Skies.