# HERA's Grand Maneuver: Braking for Didymos and the Future of Planetary Defence

An episode of [Astronomy Daily: Latest Space News](https://invisiblenetwork.ai/podcast/1642258990), 14 Oct 2026, 25 min.

Audio: https://dts.podtrac.com/redirect.mp3/mgln.ai/track/op3.dev/e/api.spreaker.com/download/episode/75775890/hera_s_grand_maneuver_braking_for_didymos_and_the_future_of_planetary_defence.mp3

Show notes Hera Hits the Brakes ESA's Hera spotted its target asteroid for the first time last week and fires its first braking burn on Thursday — 93 minutes of thrust to start stopping at Didymos and Dimorphos, the asteroid pair NASA's DART hit in 2022. Plus: Solar Orbiter traces a solar-wind switchback back to the Sun, Gemini North finds chains of giant knots in the remnant of the supernova of 1181, Webb reads the dust of Mars-sized worlds colliding, and Perseverance becomes the farthest-driving vehicle on another world. In the skywatch: the Moon meets Antares, Venus bows out, Mars and Jupiter rule the northern dawn, and the Orionids are a week away. Hera Hits the Brakes Two years after launch, Hera caught its first glimpse of Didymos from about 236,500 km away — a sub-pixel dot. On Thursday 15 October three hydrazine thrusters fire for 93 minutes (BRM-1), taking a few hundred metres per second off its approach speed; BRM-2 (~31 min) follows on 22 October, then three small transition burns. The first signal after the burn comes through ESA's New Norcia antennas in Western Australia. Hera will measure the mass of Dimorphos so DART's single orbital-period result can become a repeatable deflection technique; its CubeSats Milani and Juventas will study dust, composition and the interior. Solar Orbiter traces a switchback home Coburn et al. (Nature Astronomy, 8 Oct) used heavy-ion charge states measured inside a large switchback crossed on 2 March 2022 to show it formed by interchange reconnection in hot closed loops at the Sun's surface — with waves and turbulence taking over once it left. Both leading theories are right, at different stages. The supernova of 1181 is strung with pearls Cunningham, Caiazzo et al. (ApJ, 6 Oct) used Gemini North/GMOS to show that Pa 30's radial filaments are chains of knots ~100 billion km across. Pa 30 is the Milky Way's only known Type Iax remnant, with a surviving 'zombie' star. The knots constrain models but don't yet settle what formed them. Webb reads the wreckage of colliding worlds Su et al. (ApJ, 1 Oct) studied 21 extreme debris disks with Webb and Spitzer. About a third are silica-rich, consistent with collisions between Mars-sized planetary embryos; older systems should be silica-poor. Quick hit: Perseverance's driving record On 11 October (sol 2,006) Perseverance reached 45.22 km, passing Opportunity's 45.16 km. More than 90% of the distance was driven on AutoNav. Sources · Hera braking campaign (ESA, 7 Oct 2026) — https://www.esa.int/Space_Safety/Hera/Brake!_Time_for_ESA_s_Hera_asteroid_mission_to_go_slow · Hera's first glimpse of Didymos (ESA, 7 Oct 2026) — https://www.esa.int/ESA_Multimedia/Images/2026/10/Destination_sighted_Hera_s_first_glimpse_of_Didymos · Finding Hera's way: Flight Dynamics team in action (ESA, 7 Oct 2026) — https://www.esa.int/Space_Safety/Hera/Finding_Hera_s_way_Flight_Dynamics_team_in_action · Solar Orbiter tracks origin of magnetic switchbacks (ESA, 8 Oct 2026) — https://www.esa.int/Science_Exploration/Space_Science/Solar_Orbiter/Solar_Orbiter_tracks_origin_of_mysterious_magnetic_switchbacks · Coburn et al., Nature Astronomy, DOI 10.1038/s41550-026-02928-0 — https://www.nature.com/articles/s41550-026-02928-0 · Gemini North reveals pearl-like knots in Pa 30 (NOIRLab, 6 Oct 2026) — https://noirlab.edu/public/news/noirlab2624/ · NASA's Webb provides crash course on planet-shattering collisions (NASA) — https://science.nasa.gov/missions/webb/nasas-webb-provides-crash-course-on-planet-shattering-collisions/ · Su et al., ApJ 1010:1, DOI 10.3847/1538-4357/ae88fe — https://doi.org/10.3847/1538-4357/ae88fe · Perseverance sets off-world record for total distance driven (JPL, 12 Oct 2026) — https://www.jpl.nasa.gov/news/nasas-perseverance-sets-off-world-record-for-total-distance-driven/ Become a supporter of this podcast: https://www.spreaker.com/podcast/astronomy-daily-latest-space-news--5648921/support. Sponsor Details: Ensure your online privacy by using NordVPN. To…

## Transcript

[0:00] Anna: On Thursday, a spacecraft the size of a
[0:03] small car will turn around in deep space,
[0:06] point three of its thrusters at its
[0:08] destination and fire them for an hour and a
[0:11] half without stopping. It has been travelling
[0:13] for two years. Now it has to slow
[0:16] down.
[0:17] Avery: It's ESA's HERA, and last week it
[0:20] saw its target for the first time. A single
[0:23] bright dot that happens to be the first
[0:25] object in the solar system humans have
[0:27] deliberately moved.
[0:29] Anna: Welcome to Astronomy AstroDailyPod. I'm Anna.
[0:32] Avery: And I'm avery. It's Tuesday the 13th of
[0:35] October 2026. Coming up,
[0:38] solar Orbiter follows a kink in the solar
[0:40] wind all the way home. A supernova seen in
[0:43] the year 1181 turns out to be strung with
[0:46] pearls. And Webb reads the rubble of
[0:49] worlds colliding.
[0:50] Anna: Plus a, uh, Mars rover with a brand new
[0:53] driving record. And the Moon meets
[0:55] Antares in the skywatch. Let's get
[0:58] into it. Let's start with where Hera
[1:01] is, because what happens on Thursday only
[1:04] makes sense once you know how fast it's
[1:06] going. Hera launched on a Falcon 9
[1:09] from Cape Canaveral on 7 October 2024,
[1:12] a couple of days ahead of Hurricane Milton.
[1:14] It couldn't wait. It had a date with Mars
[1:17] and missing that window would have added
[1:19] years to the trip.
[1:22] Avery: And, um, that Mars flyby came in March last
[1:24] year. Hera swung past the planet,
[1:27] grabbed some pictures of the little moon
[1:29] Deimos on the way through and came
[1:32] out bent onto a new path and moving faster.
[1:36] Anna: Since then, ESA says Isaac Newton has
[1:39] done most of the driving, long stretches of
[1:41] coasting with a pair of deep space manoeuvres
[1:44] to tidy things up. Right now, Hera
[1:47] is moving at more than 12 kilometres per
[1:49] second relative to Earth, crossing out past
[1:52] the orbit of Mars and closing on the orbit of
[1:55] Avery: its target, which is Didymus.
[1:58] Anna: Didymus is a, uh, near Earth asteroid, about
[2:01] 780 metres across and it has
[2:04] a moon. Dimorphos is roughly
[2:06] 150 metres across and circles
[2:09] Didymus about every 12 hours.
[2:12] And on 26 September 2022,
[2:15] NASA's DART spacecraft flew straight into
[2:18] Dimorphos A at about 6 kilometres per second.
[2:21] Avery: On purpose?
[2:23] Anna: Very much on purpose. It was the first real
[2:26] test of whether you can nudge an asteroid by
[2:29] hitting it. And it worked.
[2:32] Telescopes on Earth showed the orbit of
[2:34] Dimorphos around Didymos had shortened by
[2:36] about 33 minutes. ESA likes to point
[2:39] out that Dimorphos is the first object in the
[2:42] solar system to have been changed by human
[2:44] action.
[2:45] Avery: So Last Wednesday the 7th, exactly two
[2:48] years after launch, HERA got its first
[2:50] look from about
[2:52] 236,500 kilometres away.
[2:55] Didymos showed up in the camera as a dot
[2:58] smaller than a single pixel. The team had
[3:00] to combine several images and do careful
[3:03] brightness analysis just to pick it out from
[3:05] the background stars,
[3:06] Anna: which is a lovely moment because until then,
[3:09] Didymos was a calculated point in space.
[3:12] Now the spacecraft can actually see where
[3:14] it's going.
[3:15] Avery: And now it has to stop.
[3:18] HERA is closing on Didymos, far too fast to
[3:21] arrive. So on Thursday the 15th,
[3:24] early in the European morning, the spacecraft
[3:26] will rotate so that its ring of orbit control
[3:29] thrusters faces the asteroids. Three
[3:32] of those hydrazine thrusters fire together
[3:34] and keep burning continuously for
[3:37] 93 minutes.
[3:39] Anna: That's the first braking manoeuvre, BRM1,
[3:42] and it takes a few hundred metres per second
[3:44] off Hera's speed relative to the asteroids.
[3:48] That doesn't sound like much against 12
[3:51] kilometres a second relative to Earth.
[3:53] But the number that matters is the speed
[3:56] relative to the target, and that is the one
[3:58] that has to come down to almost nothing.
[4:01] Avery: It's tricky flying too. While the big
[4:04] thrusters push, the small reaction control
[4:06] thrusters on the corners of the spacecraft
[4:09] have to hold it pointing in exactly the right
[4:11] direction for an hour and a half. The team
[4:14] ran a short Test burn on 2 October before
[4:16] building the full command sequence.
[4:19] Anna: And for our Australian listeners, there's a
[4:21] nice local detail. As soon as the burn
[4:24] ends, ESO's Flight Dynamics team will pick up
[4:27] HERA's signal through one of its 35 metre
[4:30] deep space antennas at Ah, New Norcia in
[4:33] Western Australia, north of Perth,
[4:35] Flight Dynamics engineer Francesco Castellini
[4:38] says that's when the the really hard work
[4:41] starts.
[4:42] Using the spacecraft's own navigation data,
[4:44] plus the ranging and Doppler shift carried in
[4:47] the radio signal itself to check the burn
[4:50] went in the right direction and by the right
[4:52] amount.
[4:52] Avery: On timing, ESA hasn't published the
[4:55] exact minute. Early Thursday morning
[4:58] in Europe is Thursday afternoon or evening on
[5:01] Australia's east coast and late Wednesday
[5:04] night or the small hours of Thursday in North
[5:07] America.
[5:08] Anna: Then On Thursday the 22nd comes
[5:10] BRM2, a shorter burn of about
[5:13] 31 minutes that does most of the remaining
[5:16] slowing. And it's deliberately designed to
[5:18] mop up any error from the first one.
[5:21] After that, three smaller transition
[5:23] manoeuvres at the end of the month bring
[5:25] hera's speed relative to Didymos down to
[5:27] almost zero.
[5:29] Avery: Here's the question. I suspect plenty of
[5:31] listeners are asking. Dart worked.
[5:34] We measured it. Why send a second
[5:36] spacecraft all the way out there to look at a
[5:39] rock we already know we moved?
[5:41] Anna: Because it moved isn't enough to build a
[5:44] planetary defence technique on from Earth.
[5:47] DART gave us one clean the change
[5:50] in the orbital period. What it couldn't tell
[5:53] us is how much of that change came from the
[5:55] spacecraft itself and how much came from the
[5:58] debris Dart blasted off the surface.
[6:01] When material flies off one way, the asteroid
[6:03] recoils the other way. A bit like rocket
[6:06] exhaust. That extra push depends on
[6:09] what the asteroid is made of and how well it
[6:12] holds together.
[6:13] Avery: And to untangle that, you need the mass of
[6:15] Dimorphos. Exactly. Without the
[6:18] mass, you can't turn. The orbit changed by
[6:21] 33 minutes into the impact, delivered
[6:24] this much momentum. And this much of it was a
[6:27] bonus from the ejecta. That ratio
[6:29] is the number a future mission would need if
[6:32] a real asteroid were ever heading our way.
[6:35] HERA will measure the mass, the shape, the
[6:38] interior and the impact site, or whatever
[6:41] Dart actually left behind. Because some
[6:43] modelling suggests Dimorphos may have been
[6:45] reshaped rather than simply cratered.
[6:48] That's why ESA calls it a crash scene
[6:50] investigation. And, um, HERA doesn't go in
[6:52] alone.
[6:53] Anna: It carries two cubesats.
[6:56] Milani will study composition and dust around
[6:58] the asteroids. And Juventus carries a
[7:01] low frequency radarthe first attempt to
[7:04] sound the inside of an asteroid to find
[7:07] out whether Dimorphos is solid rock or a
[7:10] loosely bound
[7:10] Avery: rubble pile, which matters
[7:13] enormously for deflection. Hitting a boulder
[7:16] and hitting a beanbag are very different
[7:17] experiments.
[7:19] Anna: Once the braking campaign is done, the plan
[7:21] is a slow, careful approach.
[7:24] ESA's Flight Dynamics team describes an early
[7:27] characterization phase in November and
[7:30] December at 25 to 30 kilometres
[7:32] from the asteroids. A detailed phase later in
[7:35] December down to 10 kilometres, then
[7:38] early next year getting as close as four
[7:41] kilometres, and eventually an experimental
[7:44] phase about one kilometre from Dimorphos.
[7:47] Avery: And a lot of that it has to do by itself.
[7:50] Flight Dynamics engineer Michael Mueller
[7:52] points out that with Rosetta, all the orbit
[7:55] calculations were done on the ground.
[7:58] Hera, once the asteroids fill its view, will
[8:00] track features on their surfaces and work out
[8:03] where it is on its own.
[8:05] Anna: A few honest caveats. First,
[8:08] this is an engineering milestone, not a
[8:11] science result. The science begins when
[8:13] Hera is close enough to see the two asteroids
[8:16] as separate objects, which it can't yet.
[8:19] Second, big burns don't always go
[8:21] exactly to plan. That's precisely why
[8:24] BRM2 is built to correct BRM1.
[8:28] So if you hear later this week that the first
[8:30] burn was a little off. That isn't a crisis.
[8:32] That's the plan working.
[8:34] Avery: And, um, third, we'll be careful with the
[8:36] arrival date. ESA describes close
[8:39] operations beginning in November. And we'll
[8:42] report HERA as arrived when it actually is,
[8:45] rather than guess.
[8:46] Anna: But step back for a second.
[8:50] Four years ago, a spacecraft hit an
[8:52] asteroid on purpose. Two years
[8:55] ago, Hera launched in front of a hurricane.
[8:58] This week, a European probe starts
[9:01] breaking beside that same asteroid. And the
[9:04] first word that the burn worked will come
[9:06] down to an antenna in the West Australian
[9:09] wheat belt.
[9:10] Avery: The the detectives are pulling up to the
[9:12] crime scene.
[9:13] Anna: They are, and we'll follow both burns
[9:17] Avery: from an asteroid to the sun.
[9:20] When NASA's Parker Solar Probe began diving
[9:22] close to The sun in 2018, it kept seeing
[9:25] something odd in the solar wind. The magnetic
[9:28] field would suddenly kink back on itself,
[9:30] snapping round almost the wrong way for
[9:33] seconds or minutes, then flipping back.
[9:36] Scientists called them switchbacks, and
[9:38] Parker found them everywhere.
[9:40] Anna: We last caught up with Parker in September
[9:42] when it matched its own speed record on its
[9:45] 29th. Close pass.
[9:47] Avery: Right. And the big argument has been where
[9:50] switchbacks come from. One camp says
[9:53] they're born at the sun's surface when
[9:55] magnetic field lines reconnect. The other
[9:57] says they grow on the way out from waves and
[10:00] turbulence in the solar wind itself.
[10:02] Anna: So which is it?
[10:05] Avery: According to a paper published last Thursday
[10:07] in Nature Astronomy, the both
[10:10] Jesse Coburn of Francis CNRS led a team
[10:13] using Europe's Solar orbiter, which on the
[10:15] 2nd of March, 2022, at a little over
[10:18] half Earth's distance from the sun, flew
[10:21] straight through an unusually large
[10:22] switchback. It took about an hour and a half
[10:25] to cross.
[10:26] Anna: And because it was so big, Solar
[10:28] Orbiter's solar wind analyzer could
[10:31] properly sample the heavy particles inside
[10:33] it, oxygen and carbon ions, which
[10:36] most switchbacks are too brief to catch.
[10:39] Avery: Those ions work like a fingerprint. How many
[10:42] electrons an oxygen or carbon atom has lost
[10:44] get set in the hot corona and then frozen
[10:47] in as the wind leaves the mix inside. This
[10:50] switchback could only have formed in hot
[10:53] closed magnetic loops at the surface of the
[10:55] sun at around a million degrees.
[10:58] Anna: Closed loops. But the solar wind
[11:01] streams out along open field lines.
[11:04] Avery: That's the key. The team calls it a smoking
[11:06] gun for interchange reconnection. An open
[11:09] field line runs into a closed loop. They snap
[11:12] and reconnect, and plasma that was trapped in
[11:15] the loop is suddenly released into space,
[11:17] carrying a kink with it. Combining the
[11:19] spacecraft's measurements with a new model
[11:21] and imagery from NASA's Solar Dynamics
[11:23] Observatory, they trace this switchback back
[11:26] to its source region.
[11:28] Anna: So where do the waves come in
[11:30] afterwards?
[11:32] Avery: Co author Stephanie Yardley at Northumbria
[11:34] University says they also see signs of waves
[11:37] and turbulence, but likely only once the
[11:39] switchback has left the Sun. Reconnection
[11:42] makes it. Turbulence carries and shapes it.
[11:45] The two theories were describing different
[11:47] stages of the same thing's life.
[11:49] Anna: One disclosure, uh, the crossing happened in
[11:51] March 2022. The paper is new this
[11:54] week, but the data are four and a half years
[11:56] old, which is normal for this kind of
[11:58] forensic work.
[12:00] Avery: And it matters. Beyond the puzzle,
[12:02] understanding how the corona heats up and
[12:04] launches the solar wind sits underneath every
[12:07] space weather forecast. ESA project
[12:10] scientist Daniel Mueller makes the point that
[12:12] no other spacecraft has the combination of
[12:14] closeness and the right instruments to make
[12:17] this connection.
[12:18] Anna: It's a nice example of two spacecraft working
[12:21] as a pair of Parker diving in close to
[12:23] find the phenomenon and solar orbiters
[12:26] standing a little further back with the tools
[12:28] to trace where it came from.
[12:31] YADFT In August of
[12:33] 1181, astronomers in China and
[12:36] Japan recorded a guest star in the part
[12:39] of the sky we call Cassiopeia. It stayed
[12:42] visible for about six months, then faded
[12:45] away. It's one of only five
[12:47] supernovae in our galaxy that people are
[12:50] known to have seen with the naked eye before
[12:52] Avery: the telescope, the others being
[12:55] 1006, 1054, which
[12:57] gave us the Crab Nebula, 1572
[13:00] and, um, 1604.
[13:02] Anna: And for centuries, nobody could find what the
[13:05] 1181 star left behind.
[13:08] Then in 2013, an amateur
[13:11] astronomer, Dana Patchik, combing through
[13:13] archival data from NASA's WISE infrared
[13:16] survey, found a faint nebula in he
[13:19] catalogued as his 30th discovery PA
[13:22] AH30, Patchk 30.
[13:25] Its age and brightness line up with the
[13:27] 1181 event, and it's now the leading
[13:30] candidate for that remnant, about 7,500 light
[13:33] years away. And it's very
[13:35] strange. Earlier images showed long,
[13:38] straight filaments radiating from a hot
[13:40] central star, like a, uh, dandelion seed head
[13:43] or a frozen firework. Nothing like
[13:46] any other supernova remnant.
[13:48] Avery: And there's a star in the middle that
[13:50] arguably shouldn't be there.
[13:52] Anna: That's the other oddity. PA 30
[13:55] is thought to be the remnant of a Type 1
[13:58] axe supernova, a weak,
[14:00] incomplete thermonuclear explosion of a white
[14:03] dwarf that failed to destroy the star.
[14:06] What's left at the centre is sometimes called
[14:08] a zombie star, and it's blowing an
[14:11] extremely fast window.
[14:13] Avery: So what's new?
[14:15] Anna: A team led by Timms Cunningham with
[14:17] Hilaria Chayazo among the co authors.
[14:20] Published in the astrophysical journal on
[14:23] 6 October using the Gemini north
[14:26] telescope on Mauna Kea. They m observed
[14:28] over six nights in July and August last year,
[14:32] mainly through a filter that isolates glowing
[14:34] sulphur. And the filaments aren't smooth
[14:37] streaks. Each one is a chain of
[14:40] knots strung like pearls.
[14:43] Avery: How big are the pearls?
[14:45] Anna: Each knot is roughly 100 billion
[14:47] kilometres across. That's wide enough to hold
[14:50] the orbits of all eight planets about 10
[14:53] times over. And they're strikingly uniform in
[14:55] size along the filaments.
[14:57] Avery: Uniform knots are a big clue for theorists.
[15:01] Something is setting that size.
[15:03] Anna: It is. And here's the honest
[15:06] bit. The paper shows the knots but
[15:09] doesn't settle what made them. There are
[15:11] competing ideas. One where the central star's
[15:14] wind sculpts the filaments. Another where the
[15:17] ejecta cooled unusually quickly.
[15:19] Gemini has given theorists a uh, much sharper
[15:22] target. Not a final answer. The
[15:25] team also found the central star shows little
[15:27] sideways recoil from the explosion. The which
[15:30] is one more constraint any model has to meet.
[15:33] Avery: Two disclosures. The observations are from
[15:36] mid-2025 and were published this month.
[15:39] And for our Southern listeners. PA30 sits
[15:42] in the far northern sky at a declination of
[15:45] about 67 degrees. It never
[15:48] rises from Cygni, so this
[15:50] Anna: one belongs to the north. Although ah, this
[15:53] faintness. It's a big telescope target for
[15:55] everyone.
[15:56] What I love is the chain of people across
[15:59] time court astronomers in
[16:01] 1181, an amateur in 2013
[16:04] and a spectrograph on a Hawaiian volcano in
[16:07] 2025 all looking at the same object.
[16:10] Avery: Staying with violence, but going back to the
[16:13] very beginning of planetary systems.
[16:15] Our moon is thought to have formed when a
[16:18] Mars sized body slammed into the young Earth.
[16:21] Collisions like that should be routine while
[16:23] rocky planets are being assembled. So why
[16:26] don't we see their aftermath more often?
[16:29] Anna: Because the evidence doesn't last.
[16:31] Avery: Right. NASA's retired Spitzer
[16:34] telescope found a rare class of system called
[16:36] extreme debris discs. Young stars with
[16:39] huge amounts of warm dust close in roughly
[16:42] where rocky planets orbit. They turn up
[16:45] around only about 1% of young stars.
[16:48] Now a team led by Kate Hsu at the Space
[16:50] Science Institute in Boulder has assembled
[16:52] the largest sample yet 21 of
[16:55] them. 16 observed with Webb's mid infrared
[16:58] instrument and 5 from Spitzer's archive. The
[17:01] paper appeared in the astrophysical journal
[17:03] on the 1st of October.
[17:05] Anna: And what did they have in common?
[17:07] Avery: Three things. Smaller dust grains than
[17:10] ordinary debris discs. A lot of warm dust
[17:13] Packed close to the star and infrared
[17:16] brightness that changes irregularly. Then
[17:18] webb spectra let the team read the minerals
[17:21] and the discs split into two families,
[17:24] silica rich and silica poor. About a
[17:27] third are silica rich and
[17:29] Anna: silica is the interesting one.
[17:31] Avery: Silica rich dust points to impacts
[17:34] violent enough to vaporise rock and the
[17:37] team's interpretation is that those come from
[17:39] collisions between planetary embryos around
[17:42] the size of Mars. Co author Agnes
[17:45] Kolsbal of Hungary's Konkoly Observatory put
[17:48] it neatly. We have no other way to study
[17:50] these planetary embryos directly because they
[17:53] are too small.
[17:54] Anna: Does it make a prediction?
[17:56] Avery: It does. If silica rich discs come
[17:59] from that early embryo smashing
[18:01] phase, you shouldn't find them around older
[18:04] stars. So older extreme debris
[18:07] discs should all be silica poor. That's
[18:09] testable as the sample grows. Caveats
[18:13] 21 Systems is the biggest sample yet,
[18:16] but still small and marsh sized
[18:19] embryos is what the composition is consistent
[18:21] with, not a direct measurement of the bodies
[18:24] involved. It links back nicely to our
[18:26] story in episode 188 on uh, simulations that
[18:29] can build a moon within hours of a giant
[18:31] impact.
[18:32] This is what the far side of that kind of
[18:35] collision might look like from light years
[18:37] away.
[18:38] Anna: A quick one before the sky. On Sunday
[18:40] the 11th, NASA's Perseverance
[18:43] rover became the farthest driving vehicle
[18:45] ever on another world. A 91
[18:48] metre drive took its odometer to
[18:50] 45.22 kilometres, just past
[18:53] the 45.16 set by Opportunity,
[18:56] which explored Mars from 2004 to
[18:59] 2018.
[19:01] Avery: Opportunity took nearly 15 years to get
[19:03] there. Perseverance did it in five and a half
[19:06] on its 2006 Martian Day.
[19:08] Anna: It had already passed the moon's records on
[19:11] the way the Apollo 17 cruise rover at
[19:14] about 35.7 kilometres and the
[19:16] Soviet Lunokhod 2 at about 39.
[19:19] Most of the credit goes to self driving.
[19:22] Perseverance has covered more than 90% of its
[19:25] distance on autonav, imaging the ground as it
[19:28] rolls, building a 3D hazard map and choosing
[19:30] its own path. Opportunity managed about
[19:33] 5% thatby and it isn't
[19:35] finished.
[19:37] Avery: Project manager Stephen Lee notes the
[19:39] original mission called for no more than
[19:41] about 20 kilometres of driving and NASA has
[19:44] just approved a first extension running to
[19:46] roughly the end of 2028. Right now
[19:49] the rover is on the western rim of Jezero in
[19:52] a region called Lac d', Sharme, heading for
[19:54] an area called Idubi to look for traces of
[19:57] ancient hydrothermal systems. That's the
[19:59] crater rim story we covered in episode two.
[20:01] Hundred.
[20:02] Anna: And every metre of it gets reported home
[20:05] through NASA's Deep Space Network, including
[20:07] the dishes at Tidbinbilla outside Canberra.
[20:10] Avery: Time to look up. And let's start with
[20:13] tomorrow evening, Wednesday the 14th, when
[20:16] the Crescent moon visits Antares, the red
[20:18] heart of Scorpius.
[20:20] Anna: Google gets the better view.
[20:22] Avery: It's genuinely split from Sydney.
[20:25] At Sunset just after 7, the moon is
[20:28] about 15% lit and sits a
[20:30] comfortable 41 degrees up in the west with
[20:33] Antares about 7 degrees away. High,
[20:36] dark and easy. And the moon stays up for
[20:39] nearly four hours.
[20:41] Anna: And in the north, tighter but much
[20:44] Avery: lower from New York at sunset about
[20:47] quarter past six, the moon is only 14 degrees
[20:50] up with Antares just over a degree
[20:53] away from Los Angeles the moon is about
[20:56] 19° up with Antares around
[20:58] 2° off, so northern listeners
[21:01] get the closer pairing. But you'll need a
[21:03] clear low western horizon soon after sunset
[21:07] from London it's right down on the
[21:09] horizon, which makes it a tough one.
[21:12] Anna: Any chance of the moon actually covering
[21:14] Antares?
[21:16] Avery: Not from any of our four cities. We
[21:18] checked and um, the closest approaches happen
[21:21] either in daylight or with the pair below the
[21:24] horizon.
[21:25] Anna: What else is up in the evening?
[21:27] Avery: For the south, Mercury is still giving its
[21:30] best show of the year. It's 24 degrees up
[21:33] at sunset from Sydney and sets about two
[21:36] hours after the Sun. Look lower in the west
[21:38] on the Moon. From New York it's only about 7
[21:41] degrees up and from London barely 3.
[21:45] And Venus is leaving us. It's heading for
[21:48] inferior conjunction passing between Earth
[21:50] and the sun around the 24th.
[21:53] From Sydney it's still about 15 degrees up at
[21:55] sunset, so catch it this week. From
[21:58] New York and London it's already gone. And
[22:01] from Los Angeles tomorrow it's under a degree
[22:03] up at sunset, which means it's effectively
[22:06] finished there.
[22:07] Anna: And Saturn?
[22:09] Avery: Saturn is just past opposition, rising
[22:12] around sunset and up all night. It's low
[22:15] in the east in the early evening for everyone
[22:17] and and highest around midnight.
[22:19] Anna: Now, uh, give the north something good.
[22:23] Avery: The pre dawn sky belongs to the north.
[22:26] On Thursday morning at nautical dawn, Mars
[22:29] and Jupiter are about 12 degrees apart and
[22:32] riding high. Mars is almost 59
[22:35] degrees up from Los Angeles and 56 from New
[22:37] York, with Jupiter in the mid-40s.
[22:40] From Sydney they're only about 23 and 18
[22:43] degrees. The pair keeps closing towards a
[22:46] close meeting in mid November.
[22:48] Anna: Moon face us.
[22:50] Avery: First quarter is Sunday the 18th at
[22:52] 1612 UTC. That's midday
[22:55] Sunday on the US East Coast.
[22:58] Nine in the morning in Los Angeles and 3:12
[23:00] on Monday. Morning in Sydney. Full Moon
[23:03] follows On the 26th, the Hunter's Moon for
[23:06] northern listeners and a
[23:07] Anna: heads up for next week, the Orionids.
[23:10] Avery: The October shower made of dust from Hallie's
[23:12] Comet peak on the night of the 21st into the
[23:15] 22nd.
[23:16] The moon will be around 80% lit, but it sets
[23:19] before 4 in the morning in all four of our
[23:22] cities, leaving a dark window before dawn
[23:24] at 4am The Radiant near Orion's
[23:27] raised club is about 60 to 66 degrees
[23:30] up from New York and Los Angeles, about 51
[23:33] from London and about 37 from Sydney,
[23:36] so the north is favoured. But this is a
[23:38] shower everyone can see under dark skies,
[23:41] perhaps a couple of dozen an hour at best.
[23:44] Anna: And our standing Safety note Always
[23:47] never
[23:48] Avery: look directly at the sun with your eyes or
[23:50] through binoculars, a camera or a telescope.
[23:53] If you ever observe the sun, including during
[23:56] a, uh, partial eclipse, use only certified
[23:58] solar viewers or filters that meet the ISO
[24:01] 123122 international
[24:04] safety standard.
[24:05] Check them for scratches or damage first and
[24:08] supervise children. Ordinary sunglasses are
[24:11] not safe. With two solar eclipses coming
[24:14] in 2027, it's worth getting proper filters
[24:17] well ahead of time.
[24:18] Anna: That's Astronomy daily for Tuesday
[24:21] 13th October. HERA's first
[24:24] braking burn is on Thursday and we'll bring
[24:26] you the result once ESA confirms it.
[24:29] Avery: Show notes, sources and every link are at
[24:32] astronomydaily IO where you can also sign up
[24:35] for the newsletter and send us questions
[24:36] through the contact form. Listener questions
[24:39] have shaped more than one segment on this
[24:40] show.
[24:41] Anna: We are AstroDaily Pod on social media
[24:44] and if you're enjoying this show, a uh,
[24:46] rating or review in your podcast app
[24:48] genuinely helps other people find us.
[24:51] Avery: Astronomy AstroDailyPod is part of the
[24:53] bites.com podcast network. I'm M.
[24:56] Avery.
[24:56] Anna: And I'm Anna. Clear Skies
[25:00] Astronomy Day
[25:03] Stories
[25:06] Love.
[25:11] Story.
[25:19] For soul.

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