Two black holes caught feeding side by side just 1.3 billion years after the Big Bang. JWST and ALMA confirm LID-1166, the first close dual AGN found beyond the nearby universe. Plus: Swift's final days and NASA's call for ideas to save Hubble, Rubin finds Neptune's missing trailing Trojans as Lucy enters Jupiter's, TRACERS' first look at where the solar wind gets in, and a both-hemispheres skywatch built around the Mars-Jupiter meeting on 16 November. Two Hearts in One Galaxy (LID-1166) JWST/NIRSpec integral-field spectroscopy resolves two feeding black holes ~1.5 kpc (~4,900 ly) apart at z~4.5; ALMA [CII] finds matching cold gas around each. Both appear super-Eddington yet already sit on the local black hole-host mass relation. One system, projected separation; preprint posted July, published in Nature Astronomy this week. Living on Borrowed Altitude Swift ended operations on 20 October and is expected to re-enter in early November. NASA's 29 October Request for Information asks industry about boosting, servicing or safely de-orbiting Hubble, likely to re-enter in 2033-34. Not a commitment; responses due 30 November. Trojan Week Rubin early data confirms 2025 MH348 and 2025 NN80 as long-lived trailing Neptune Trojans, plus candidate 2025 MD138 (Schwamb et al., ApJL). Lucy becomes the first spacecraft to enter the Jupiter Trojan region; Eurybates flyby 11 August 2027. TRACERS: Where the Solar Wind Gets In First results (JGR: Space Physics) suggest cusp reconnection is largely spatial rather than temporal. Mission extended to spring 2027. Quick hits BepiColombo Mercury orbit insertion 21 November; Starship Flight 15 targeted November with a double catch attempt; Voyager 1 one light-day from Earth around 18 November. Skywatch Mars and Jupiter 1.2 degrees apart before dawn on 16 November; Venus, a thin Moon and Spica low at dawn 7-10 November; Saturn high in southern evenings; zodiacal light around New Moon (9 Nov); Leonids 17-18 November; supermoon 24 November. ISO 12312-2 solar safety reminder.
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This episode includes AI-generated content.
00:00:00 --> 00:00:02 Anna: Welcome back for another week of the latest
00:00:03 --> 00:00:04 in space and astronomy news.
00:00:05 --> 00:00:08 12 and a half billion years ago, in a galaxy
00:00:08 --> 00:00:11 so buried in dust that Hubble never saw it,
00:00:11 --> 00:00:14 two black holes were feeding at the same
00:00:14 --> 00:00:16 time, less than 5 light years apart.
00:00:17 --> 00:00:20 Avery: And this week, a team using Webb and ALMA
00:00:20 --> 00:00:23 showed us both of them, the first time a pair
00:00:23 --> 00:00:24 that close has been caught that far back.
00:00:25 --> 00:00:28 Anna: Also today, one telescope falls this
00:00:28 --> 00:00:31 week and another asks for a lifeline.
00:00:32 --> 00:00:35 Neptune's missing Trojans start turning up
00:00:35 --> 00:00:38 and twin satellites tell us where the solar
00:00:38 --> 00:00:39 wind gets in.
00:00:39 --> 00:00:40 Avery: I'm, um, Avery.
00:00:40 --> 00:00:43 Anna: I'm Anna and this is Astronomy
00:00:43 --> 00:00:43 AstroDailyPod.
00:00:43 --> 00:00:44 Anna: Let's get going, then.
00:00:45 --> 00:00:48 Anna: Let's start with a problem that has nagged at
00:00:48 --> 00:00:50 astronomers for decades. Almost
00:00:50 --> 00:00:53 every big galaxy has a supermassive
00:00:53 --> 00:00:56 black hole at its centre. Galaxies grow
00:00:56 --> 00:00:59 by merging. So when two galaxies merge,
00:00:59 --> 00:01:02 you should get two black holes in one system
00:01:02 --> 00:01:04 sinking towards each other.
00:01:04 --> 00:01:07 Avery: And in the early universe, mergers were far
00:01:07 --> 00:01:10 more common than they are today. Galaxies
00:01:10 --> 00:01:12 were closer together, richer in gas and
00:01:12 --> 00:01:14 running into each other all the time.
00:01:15 --> 00:01:17 Anna: So you would expect the young universe to be
00:01:17 --> 00:01:20 full of these pairs. Two black holes both
00:01:20 --> 00:01:23 switched on and feeding a few thousand light
00:01:23 --> 00:01:25 years apart from. Astronomers call them, um,
00:01:25 --> 00:01:28 Dual Active Galactic Nuclei. Dual
00:01:28 --> 00:01:29 AGN for short.
00:01:29 --> 00:01:32 Avery: But here is the problem. Until
00:01:32 --> 00:01:35 now, every confirmed pair that close
00:01:35 --> 00:01:38 under about 3 kiloparsecs, or roughly
00:01:38 --> 00:01:41 10 light years, has been in the nearby
00:01:41 --> 00:01:43 universe. Go further back in time
00:01:44 --> 00:01:45 and they vanish from the record.
00:01:46 --> 00:01:48 Anna: Which is the opposite of what theory
00:01:48 --> 00:01:51 predicts. Either of the pairs aren't there
00:01:51 --> 00:01:53 or we've been missing them.
00:01:53 --> 00:01:56 Avery: Enter lid 1166.
00:01:56 --> 00:01:59 It was first flagged as an X ray source in
00:01:59 --> 00:02:02 the Chandra Cosmos Legacy Survey.
00:02:02 --> 00:02:05 Something was clearly feeding hard.
00:02:05 --> 00:02:08 But in even the deepest Hubble images, there
00:02:08 --> 00:02:10 was essentially nothing to see.
00:02:11 --> 00:02:14 Anna: That's the signature of heavy obscuration.
00:02:14 --> 00:02:17 The X rays punch through the dust. Visible
00:02:17 --> 00:02:17 light doesn't.
00:02:18 --> 00:02:21 Avery: So a team led by Haewon Su at the
00:02:21 --> 00:02:23 International Gemini Observatory, part of
00:02:23 --> 00:02:26 NSF's Noir Lab, pointed the James Webb
00:02:26 --> 00:02:29 Space Telescope at it using NIRSPEC in its
00:02:29 --> 00:02:30 integral field mode.
00:02:31 --> 00:02:34 Anna: Integral field spectroscopy is the key
00:02:34 --> 00:02:37 here. Instead of one spectrum for the whole
00:02:37 --> 00:02:39 object, you get a spectrum for every small
00:02:39 --> 00:02:42 patch of it. A map where every pixel is a
00:02:42 --> 00:02:43 rainbow.
00:02:43 --> 00:02:45 Avery: And in that map, lid
00:02:45 --> 00:02:48 1166 split in two.
00:02:49 --> 00:02:51 Two separate glowing regions about
00:02:52 --> 00:02:54 one and a half kiloparsecs apart. That's
00:02:54 --> 00:02:57 roughly 4900 light years.
00:02:58 --> 00:03:00 And they are moving relative to each other
00:03:00 --> 00:03:02 along our line of sight at about
00:03:02 --> 00:03:05 164 kilometres per second,
00:03:05 --> 00:03:08 Anna: the object sits at a redshift of about
00:03:08 --> 00:03:11 four and a half. Or seeing it as it was,
00:03:11 --> 00:03:14 around 1.3 billion years after the
00:03:14 --> 00:03:15 big bang.
00:03:15 --> 00:03:18 Avery: Two glowing blobs isn't enough on its own.
00:03:18 --> 00:03:21 They could be two star forming clumps.
00:03:21 --> 00:03:24 So the team looked for the fingerprint of a
00:03:24 --> 00:03:26 feeding black broad hydrogen
00:03:26 --> 00:03:27 alpha emission.
00:03:28 --> 00:03:30 Anna: When gas orbits very close to a black
00:03:30 --> 00:03:33 hole, it moves fast enough to smear
00:03:33 --> 00:03:36 its spectral lines out, sometimes by
00:03:36 --> 00:03:38 thousands of kilometres per second.
00:03:39 --> 00:03:41 Star forming regions don't do that.
00:03:42 --> 00:03:44 Avery: And both components showed it, including a
00:03:44 --> 00:03:47 compact broad line source sitting off the
00:03:47 --> 00:03:49 main nucleus on the companion
00:03:49 --> 00:03:52 two engines both running.
00:03:52 --> 00:03:55 Anna: There's an obvious trap to rule out and the
00:03:55 --> 00:03:58 team addressed it. Gravitational lensing.
00:03:58 --> 00:04:01 A foreground mass can split one distant
00:04:01 --> 00:04:02 source into two images.
00:04:03 --> 00:04:06 Avery: But lensed images of the same object share
00:04:06 --> 00:04:09 the same redshift and the same line shapes.
00:04:09 --> 00:04:11 These two don't. Slightly different
00:04:11 --> 00:04:14 redshifts, different broad line profiles,
00:04:15 --> 00:04:16 two different objects.
00:04:16 --> 00:04:19 Anna: And then there's the independent check from
00:04:19 --> 00:04:21 the southern hemisphere. The
00:04:21 --> 00:04:24 Atacama Large Millimetre Submillimeter
00:04:24 --> 00:04:27 Array in northern Chile looked at the same
00:04:27 --> 00:04:30 system in a light of ionised carbon, but
00:04:30 --> 00:04:33 at 158 microns that
00:04:33 --> 00:04:34 traces cold gas.
00:04:35 --> 00:04:38 Avery: Alma found two cold gas components too,
00:04:38 --> 00:04:41 sitting with the same two nuclei and moving
00:04:41 --> 00:04:42 in step with them.
00:04:42 --> 00:04:45 Anna: That matters, because one alternative is that
00:04:45 --> 00:04:47 the second black hole was kicked out of its
00:04:47 --> 00:04:50 galaxy or flung loose in a three way
00:04:50 --> 00:04:53 gravitational encounter. A black hole
00:04:53 --> 00:04:56 thrown out like that tends to travel
00:04:56 --> 00:04:59 naked without its own gas around it.
00:04:59 --> 00:05:02 Avery: These two each have their own reservoir.
00:05:02 --> 00:05:04 That says two gas rich galaxies
00:05:05 --> 00:05:07 close to the end of a merger, each still
00:05:07 --> 00:05:09 carrying its own black hole into the middle.
00:05:09 --> 00:05:11 Anna: Here is where it gets interesting.
00:05:12 --> 00:05:14 Both black holes appear to be accreting above
00:05:14 --> 00:05:16 the Eddington limit.
00:05:16 --> 00:05:18 Avery: Regular listeners will remember the Eddington
00:05:18 --> 00:05:20 limit from our episode 197 lead.
00:05:21 --> 00:05:22 It's the feeding rate at uh, which the
00:05:22 --> 00:05:25 outward push of radiation balances the
00:05:25 --> 00:05:28 inward pull of gravity. Go beyond it and in
00:05:28 --> 00:05:30 a simple picture, you'd blow your own food
00:05:30 --> 00:05:30 away.
00:05:30 --> 00:05:33 Anna: In a dense, dusty, gas choked
00:05:33 --> 00:05:36 merger, though, that simple picture breaks
00:05:36 --> 00:05:36 down.
00:05:37 --> 00:05:40 Radiation gets trapped and can't push the
00:05:40 --> 00:05:43 gas out as efficiently. So the black
00:05:43 --> 00:05:44 holes keep eating.
00:05:45 --> 00:05:47 Avery: And yet, despite growing that fast,
00:05:48 --> 00:05:50 both black holes already sit on the
00:05:50 --> 00:05:52 relationship we see in today's universe
00:05:53 --> 00:05:55 between a black hole's mass and the mass of
00:05:55 --> 00:05:58 its host galaxy. The local relation
00:05:58 --> 00:06:00 for massive elliptical galaxies.
00:06:01 --> 00:06:02 Within the uncertainties,
00:06:03 --> 00:06:05 Anna: that's the part I find genuinely striking.
00:06:06 --> 00:06:09 In nearby galaxies, the black hole in the
00:06:09 --> 00:06:11 galaxy seem to have grown in Lockstep.
00:06:12 --> 00:06:14 Nobody has been sure when that lockstep was
00:06:14 --> 00:06:15 established.
00:06:15 --> 00:06:18 Avery: Lid 1166 suggests it may be
00:06:18 --> 00:06:21 set early. During exactly this kind of
00:06:21 --> 00:06:24 rapid obscured merger driven growth,
00:06:24 --> 00:06:27 the two grew together inside the dust where
00:06:27 --> 00:06:28 we couldn't see.
00:06:28 --> 00:06:31 Anna: The team's own conclusion is that this points
00:06:31 --> 00:06:33 to a missing population,
00:06:34 --> 00:06:37 heavily obscured merger driven dual
00:06:37 --> 00:06:39 AGN at high redshift sitting in the
00:06:39 --> 00:06:42 gap our surveys have been leaving. It's worth
00:06:42 --> 00:06:44 picturing what happens next to a pair like
00:06:44 --> 00:06:47 this because it's a long road. At
00:06:47 --> 00:06:50 a separation of a, uh, kiloparsec or so,
00:06:50 --> 00:06:53 each black hole is still wrapped in the core
00:06:53 --> 00:06:54 of its own galaxy.
00:06:54 --> 00:06:57 Avery: As they move through the merged galaxy, stars
00:06:57 --> 00:07:00 and gas, they drag a, uh, wake behind them.
00:07:00 --> 00:07:03 That wake pulls back on them, a process
00:07:03 --> 00:07:04 called dynamical friction.
00:07:05 --> 00:07:07 And they spiral inwards over many millions of
00:07:07 --> 00:07:08 years,
00:07:08 --> 00:07:11 Anna: get down to a few parsecs and they become a
00:07:11 --> 00:07:14 bound pair, a true binary.
00:07:14 --> 00:07:16 From there they shed energy by flinging
00:07:16 --> 00:07:19 nearby stars away and by starring the
00:07:19 --> 00:07:20 gas around them.
00:07:21 --> 00:07:24 Avery: Only in the very last stage, when
00:07:24 --> 00:07:26 they're within a small fraction of a light
00:07:26 --> 00:07:28 year of each other, does gravitational
00:07:29 --> 00:07:31 radiation take over and drive them to
00:07:31 --> 00:07:32 merge.
00:07:33 --> 00:07:35 Anna: So LID 1166 is an early
00:07:35 --> 00:07:38 chapter, the ending comes much later,
00:07:38 --> 00:07:41 and it happens in gravitational waves rather
00:07:41 --> 00:07:41 than light.
00:07:42 --> 00:07:44 Avery: And there's a gravitational wave thread too.
00:07:45 --> 00:07:48 Pairs like this are the ancestors of the
00:07:48 --> 00:07:51 black hole binaries that eventually merge.
00:07:51 --> 00:07:54 Those mergers feed the background hum, um,
00:07:54 --> 00:07:56 that pulsar timing arrays are now picking up.
00:07:57 --> 00:08:00 And in the2030s, they're what Lisa is being
00:08:00 --> 00:08:01 built to hear directly.
00:08:01 --> 00:08:03 Anna: Echoes of our little red dot story from
00:08:03 --> 00:08:06 episode 197 and the Overmass of black
00:08:06 --> 00:08:09 holes E. Rosita found back in episode 188.
00:08:10 --> 00:08:12 The early universe keeps telling us its black
00:08:12 --> 00:08:14 holes grew faster and earlier than we
00:08:14 --> 00:08:16 assumed. This is one of the ways they may
00:08:16 --> 00:08:17 have done it.
00:08:18 --> 00:08:20 Avery: Three honest caveats. First, this is
00:08:20 --> 00:08:23 one system. One object can show a phase
00:08:23 --> 00:08:25 exists. It can't tell us how common that
00:08:25 --> 00:08:26 phase is.
00:08:26 --> 00:08:28 Anna: Second, the separation is
00:08:28 --> 00:08:31 projected. We see the pair on the
00:08:31 --> 00:08:34 sky in three dimensions. They could
00:08:34 --> 00:08:37 be somewhat farther apart, though not
00:08:37 --> 00:08:38 closer.
00:08:38 --> 00:08:41 Avery: And third, when this first appeared as a
00:08:41 --> 00:08:44 preprint, Ana Trindari Falcao at NASA
00:08:44 --> 00:08:46 Goddard, who wasn't involved, told Life
00:08:46 --> 00:08:49 Science the signal held up across several
00:08:49 --> 00:08:51 different ways of subtracting the light, but
00:08:51 --> 00:08:53 that a deeper follow up would be worthwhile
00:08:53 --> 00:08:56 to confirm two black holes rather than one
00:08:56 --> 00:08:57 plus leftover glow,
00:08:58 --> 00:09:01 Anna: which is a fair standard and a disclosure
00:09:01 --> 00:09:03 from us. The paper was posted as a
00:09:03 --> 00:09:06 preprint in July and got some coverage then.
00:09:07 --> 00:09:09 What's new is that it's now been through peer
00:09:09 --> 00:09:12 review and published in Nature Astronomy this
00:09:12 --> 00:09:12 week.
00:09:12 --> 00:09:15 Avery: One last detail. I like lid
00:09:15 --> 00:09:18 1166 sits in the Cosmos field,
00:09:18 --> 00:09:20 right on the celestial equator.
00:09:20 --> 00:09:23 Whether you're in Sydney or Seattle,
00:09:23 --> 00:09:26 it's in your sky. You just need a
00:09:26 --> 00:09:28 space telescope and a radio array in the
00:09:28 --> 00:09:29 Atacama to see what's in it.
00:09:31 --> 00:09:33 Anna: Speaking of telescopes, let's move on to our
00:09:33 --> 00:09:34 next story. Today,
00:09:35 --> 00:09:38 Avery: two telescopes, one enemy, the
00:09:38 --> 00:09:38 atmosphere.
00:09:39 --> 00:09:41 And this week both stories come to a head
00:09:42 --> 00:09:44 Anna: start with Swift. NASA's Neil Gehrel Swift
00:09:44 --> 00:09:47 Observatory ended operations on 20 October
00:09:48 --> 00:09:50 after sinking to about 275 kilometres.
00:09:51 --> 00:09:53 At that height it could no longer hold its
00:09:53 --> 00:09:55 attitude against drag and the team at Penn
00:09:55 --> 00:09:57 State sent the command that ended the
00:09:57 --> 00:09:58 mission.
00:09:58 --> 00:09:59 Avery: This is the thread that started with your
00:09:59 --> 00:10:02 messages through the contact form back in
00:10:02 --> 00:10:05 episode 187 when Link was trying to
00:10:05 --> 00:10:06 reach Swift and boost it.
00:10:06 --> 00:10:09 Link never latched on and re entered itself
00:10:09 --> 00:10:12 on the 25th of September. Swift went back to
00:10:12 --> 00:10:14 doing science, which raised its drag and the
00:10:14 --> 00:10:15 end came quickly.
00:10:15 --> 00:10:18 Anna: As of this weekend, it's still up there.
00:10:19 --> 00:10:21 The latest space track prediction is centred
00:10:21 --> 00:10:24 on early Wednesday 4th November UTC,
00:10:24 --> 00:10:27 but with a window of more than two weeks
00:10:27 --> 00:10:30 either side. The Aerospace Corporation
00:10:30 --> 00:10:32 has a similar central estimate with about a
00:10:32 --> 00:10:33 uh, day of uncertainty,
00:10:34 --> 00:10:37 Avery: which is normal. Re entry predictions only
00:10:37 --> 00:10:40 tighten in the last hours. Most of
00:10:40 --> 00:10:42 the roughly one and a half ton spacecraft is
00:10:42 --> 00:10:45 expected to burn up. Its orbit is tilted
00:10:45 --> 00:10:48 about 20 degrees to the equator, so the track
00:10:48 --> 00:10:51 stays over the tropics, including Australia's
00:10:51 --> 00:10:51 far north.
00:10:52 --> 00:10:53 Anna: Now Hubble.
00:10:54 --> 00:10:56 On 29 October, NASA issued a request
00:10:56 --> 00:10:59 for information asking industry what it could
00:10:59 --> 00:11:02 do 3 Boost
00:11:02 --> 00:11:05 Hubble to a higher orbit, service it to
00:11:05 --> 00:11:07 improve its capabilities or carry out a
00:11:07 --> 00:11:09 safe controlled reentry.
00:11:10 --> 00:11:12 Avery: Hubble has no propulsion of its own.
00:11:13 --> 00:11:16 NASA's analysis puts its likely reentry in
00:11:16 --> 00:11:18 the 2033-2034 timeframe,
00:11:19 --> 00:11:21 which means any mission would need to fly by
00:11:21 --> 00:11:22 2032.
00:11:22 --> 00:11:25 Anna: Administrator Jared Isaacman framed it as
00:11:25 --> 00:11:28 value for money. If there are cost effective
00:11:28 --> 00:11:31 ways to extend the life of an asset already
00:11:31 --> 00:11:33 in orbit, NASA owes it to taxpayers
00:11:33 --> 00:11:35 and scientists to look.
00:11:36 --> 00:11:39 Science chief Nikki Fox pointed to how fast
00:11:39 --> 00:11:41 commercial satellite capture and servicing
00:11:41 --> 00:11:42 has matured
00:11:42 --> 00:11:44 Avery: and to be clear about what this is and
00:11:44 --> 00:11:47 isn't, it's a request for information
00:11:48 --> 00:11:50 open until 30 November. It is not
00:11:50 --> 00:11:53 a contract and not a commitment to a
00:11:53 --> 00:11:53 mission.
00:11:54 --> 00:11:57 Anna: Zwift is the cautionary Tale sitting right
00:11:57 --> 00:11:59 next to it. A fast cheap commercial
00:11:59 --> 00:12:02 rescue was tried and it didn't connect.
00:12:03 --> 00:12:06 Hubble has years rather than months, which is
00:12:06 --> 00:12:08 exactly the margin Swift never had.
00:12:08 --> 00:12:11 Avery: Our next story is headlined Trojan
00:12:11 --> 00:12:13 Week. What's this all about?
00:12:14 --> 00:12:16 Anna: Every planet has two gravitational sweet
00:12:16 --> 00:12:19 spots on its own orbit 60 degrees ahead
00:12:19 --> 00:12:22 and 60 degrees behind the Lagrange
00:12:22 --> 00:12:24 points. L4 and L5.
00:12:25 --> 00:12:27 Asteroids that settle there travel with the
00:12:27 --> 00:12:30 planet for billions of years. We call them
00:12:30 --> 00:12:31 Trojans.
00:12:31 --> 00:12:34 Avery: And um, this week Trojans turn up at uh, both
00:12:34 --> 00:12:35 ends of the outer solar system.
00:12:36 --> 00:12:39 Anna: First Neptune. Neptune's Trojans
00:12:39 --> 00:12:41 lead and trail it around the sun.
00:12:41 --> 00:12:44 But the trailing cloud at L5 has been
00:12:44 --> 00:12:47 very hard to study because for more than a
00:12:47 --> 00:12:49 decade it has sat in front of the crowded
00:12:49 --> 00:12:51 starfields towards the centre of the Milky
00:12:51 --> 00:12:51 Way.
00:12:52 --> 00:12:55 Avery: Try picking out a faint moving dot against
00:12:55 --> 00:12:57 millions of background stars.
00:12:58 --> 00:13:00 Now that cloud is drifting out of the densest
00:13:00 --> 00:13:03 part of the sky. And Rubin Observatory,
00:13:03 --> 00:13:06 still in its early data, has gone looking.
00:13:06 --> 00:13:09 Anna: A UH Tim M led by Meg Schwab at Queen's
00:13:09 --> 00:13:11 University Belfast confirmed two objects
00:13:12 --> 00:13:14 2025 MH348 and
00:13:14 --> 00:13:17 2025NN80 as long
00:13:17 --> 00:13:20 lived trailing Trojans and added a third
00:13:20 --> 00:13:23 candidate, 2025 MD138.
00:13:23 --> 00:13:26 In Schwam's words, that doubles the number of
00:13:26 --> 00:13:28 known objects in this population on long
00:13:28 --> 00:13:29 lived orbits.
00:13:29 --> 00:13:32 Avery: Rubin's colour filters also suggest the
00:13:32 --> 00:13:34 leading and trailing Trojans have similar
00:13:34 --> 00:13:37 surfaces, which is a clue that both
00:13:37 --> 00:13:39 clouds were filled from the same population
00:13:40 --> 00:13:42 of primitive bodies early on. The
00:13:42 --> 00:13:44 paper is in the Astrophysical Journal
00:13:44 --> 00:13:45 Letters.
00:13:45 --> 00:13:47 Anna: Earlier modelling from the same group
00:13:47 --> 00:13:50 predicted Rubin's full survey could find
00:13:50 --> 00:13:53 somewhere around 130 to
00:13:53 --> 00:13:55 300 Neptune Trojans. These
00:13:55 --> 00:13:57 are the first steps of that.
00:13:57 --> 00:14:00 Avery: And here's the southern bonus
00:14:00 --> 00:14:03 tonight. Neptune's trailing L5
00:14:03 --> 00:14:06 point sits in Capricornis, about
00:14:06 --> 00:14:09 53 degrees up from Sydney. Once it's fully
00:14:09 --> 00:14:12 dark from Los Angeles it's about 34.
00:14:12 --> 00:14:15 New York, 28, London 18.
00:14:15 --> 00:14:18 Too faint for any backyard telescope, but
00:14:18 --> 00:14:20 it's right over our heads.
00:14:20 --> 00:14:23 Anna: Ben Jupiter. NASA's Lucy
00:14:23 --> 00:14:25 mission, launched in October 2021
00:14:26 --> 00:14:29 has travelled more than 2.2 billion
00:14:29 --> 00:14:31 miles and has now entered the region of
00:14:31 --> 00:14:34 Jupiter's leading Trojans, the first
00:14:34 --> 00:14:35 spacecraft ever to do so.
00:14:36 --> 00:14:38 Avery: The Trojans there are spread out
00:14:39 --> 00:14:41 more than 6 million miles apart on average,
00:14:42 --> 00:14:44 so for now they're just points of light
00:14:44 --> 00:14:47 moving against the stars. Lucy's
00:14:47 --> 00:14:50 first Trojan encounter with EuryBates is
00:14:50 --> 00:14:52 on 11 August 2027.
00:14:52 --> 00:14:55 Anna: Then Polymelli, Lucas and
00:14:55 --> 00:14:58 Oris through 2028, back
00:14:58 --> 00:15:01 past Earth in 2030 and over to the
00:15:01 --> 00:15:03 trailing swarm to visit the binary pair
00:15:03 --> 00:15:05 Patroclus and Manoechius in March
00:15:05 --> 00:15:06 2033.
00:15:07 --> 00:15:10 Avery: Two telescopes, two giant planets.
00:15:10 --> 00:15:13 One idea. Leftovers parked in
00:15:13 --> 00:15:16 gravitational safe harbours since the planets
00:15:16 --> 00:15:16 moved into place.
00:15:17 --> 00:15:20 Anna: Onto our next story, another one with an
00:15:20 --> 00:15:23 intriguing headline. Tracers where the
00:15:23 --> 00:15:25 solar wind gets in.
00:15:25 --> 00:15:28 Avery: When the solar wind hits Earth's magnetic
00:15:28 --> 00:15:30 field, most of it is turned aside.
00:15:31 --> 00:15:34 But where the sun's magnetic field lines meet
00:15:34 --> 00:15:36 ours, they can snap and reconnect
00:15:37 --> 00:15:39 and that opens a door. It's called
00:15:39 --> 00:15:42 magnetic reconnection and it's how solar
00:15:42 --> 00:15:43 energy gets into our space environment.
00:15:44 --> 00:15:47 Anna: Over each magnetic pole, there's a funnel
00:15:47 --> 00:15:49 shaped region called the polar cusp, where
00:15:49 --> 00:15:52 those particles pour straight down towards
00:15:52 --> 00:15:54 the upper atmosphere. NASA's
00:15:54 --> 00:15:57 Tracers mission flies two spacecraft,
00:15:57 --> 00:15:59 one behind the other, through the southern
00:15:59 --> 00:16:01 cusp several times a day.
00:16:01 --> 00:16:04 Avery: Why two? Because with one spacecraft
00:16:04 --> 00:16:07 you can't tell whether a change you see is
00:16:07 --> 00:16:10 happening in time, the process switching on
00:16:10 --> 00:16:12 and off, or in space, the process
00:16:12 --> 00:16:15 happening in a different place. The second
00:16:15 --> 00:16:17 spacecraft following the first through the
00:16:17 --> 00:16:18 same region breaks that tie.
00:16:19 --> 00:16:22 Anna: The first science paper is now out in the
00:16:22 --> 00:16:24 Journal of Geophysical Research Space
00:16:24 --> 00:16:27 Physics. Using the ion instruments on
00:16:27 --> 00:16:30 both satellites, the team finds that
00:16:30 --> 00:16:33 reconnection here looks largely spatial.
00:16:33 --> 00:16:36 What's changing is mostly where it's
00:16:36 --> 00:16:38 happening, not how it's evolving in time.
00:16:39 --> 00:16:41 Avery: Deputy Principal Investigator Stephen
00:16:41 --> 00:16:44 Fuselier at the Southwest Research Institute
00:16:44 --> 00:16:47 called it an important first step and
00:16:47 --> 00:16:49 NASA is careful to add that future
00:16:49 --> 00:16:51 measurements will need to confirm it.
00:16:51 --> 00:16:54 Anna: It's also a recovery story. One of
00:16:54 --> 00:16:57 the two satellites ran into trouble shortly
00:16:57 --> 00:17:00 after launch. In 2025, the team
00:17:00 --> 00:17:02 re established contact, got routine science
00:17:02 --> 00:17:05 going and in September, NASA, uh,
00:17:05 --> 00:17:08 extended the prime mission into spring 2027.
00:17:09 --> 00:17:12 Avery: And it pairs nicely with Saturday's lead on
00:17:12 --> 00:17:14 the May 2024 superstorm.
00:17:15 --> 00:17:17 That was what happens deep inside the
00:17:17 --> 00:17:19 magnetic field when the door's wide open.
00:17:20 --> 00:17:22 Traitors is watching the door itself.
00:17:23 --> 00:17:24 High over the far south
00:17:25 --> 00:17:26 Avery: now,
00:17:26 --> 00:17:27 Anna: a few quick ones.
00:17:27 --> 00:17:30 Avery: BepiColombo. The joint European and Japanese
00:17:30 --> 00:17:33 mission is now less than three weeks from
00:17:33 --> 00:17:36 Mercury. ESA has orbit insertion
00:17:36 --> 00:17:39 set for 21st November, with Japan's
00:17:39 --> 00:17:42 Mio orbiters separating around the 9th and
00:17:42 --> 00:17:45 10th of December. And routine science from
00:17:45 --> 00:17:46 April 2027.
00:17:47 --> 00:17:49 Anna: Starship Flight 15 is targeted for November,
00:17:49 --> 00:17:52 with SpaceX aiming to catch both the booster
00:17:52 --> 00:17:54 and the ship with the tower arms for the
00:17:54 --> 00:17:56 first time. No launch date has been published
00:17:56 --> 00:17:57 yet
00:17:58 --> 00:18:01 Avery: and Voyager 1 is closing in on a milestone.
00:18:01 --> 00:18:03 We've been Counting down to around the 18th
00:18:03 --> 00:18:06 of November. It'll be one light day from
00:18:06 --> 00:18:08 Earth. A radio signal sent from here will
00:18:08 --> 00:18:10 take a full 24 hours to reach it.
00:18:11 --> 00:18:14 Anna: Launched in 1977. Still
00:18:14 --> 00:18:14 talking
00:18:15 --> 00:18:18 Avery: now onto Skywatch and an honest note
00:18:18 --> 00:18:21 first. This fortnight the morning sky belongs
00:18:21 --> 00:18:23 to the north, and, um, we'll say so.
00:18:23 --> 00:18:25 But the south has the better evenings, so
00:18:25 --> 00:18:26 stay with us.
00:18:26 --> 00:18:29 Anna: Mars and Jupiter are in Leo before dawn and
00:18:29 --> 00:18:32 they're closing on the morning of the 16th of
00:18:32 --> 00:18:35 November. They'll be about 1.2 degrees apart,
00:18:35 --> 00:18:37 roughly two full moon widths.
00:18:38 --> 00:18:41 Jupiter is much the brighter around magnitude
00:18:41 --> 00:18:43 -2, with Mars A little dimmer orange
00:18:43 --> 00:18:44 point beside it.
00:18:45 --> 00:18:48 Avery: From Los Angeles and New York, the pear is
00:18:48 --> 00:18:51 more than 60 degrees up at first light from
00:18:51 --> 00:18:54 London, 53 from Sydney,
00:18:54 --> 00:18:56 about 30 degrees up in the northeast.
00:18:57 --> 00:18:59 Lower for us, but still clear of the trees.
00:19:00 --> 00:19:02 Anna: Venus is back in the morning sky
00:19:03 --> 00:19:05 after passing between us and the sun
00:19:06 --> 00:19:08 on the morning of the 7th. A, uh, 3%
00:19:08 --> 00:19:11 crescent moon sits about 4 degrees from
00:19:11 --> 00:19:14 it. And around the 10th, Venus
00:19:14 --> 00:19:17 passes just over a degree from Spica,
00:19:17 --> 00:19:18 the brightest star in Virgo.
00:19:19 --> 00:19:22 Avery: That's a low twilight event at civil
00:19:22 --> 00:19:22 dawn.
00:19:22 --> 00:19:25 Venus is around 12 degrees up from Los
00:19:25 --> 00:19:27 Angeles and New York, nine from London
00:19:28 --> 00:19:31 and only eight to 10 from Sydney. Find
00:19:31 --> 00:19:33 a clear eastern horizon and go out about half
00:19:33 --> 00:19:35 an hour before sunrise.
00:19:35 --> 00:19:38 Anna: Saturn is the evening planet. At
00:19:38 --> 00:19:41 dusk on Tuesday it's nearly 37
00:19:41 --> 00:19:43 degrees up from Sydney against
00:19:43 --> 00:19:46 22 from Los Angeles, 19
00:19:46 --> 00:19:49 from New York and 13 from
00:19:49 --> 00:19:51 London. Its rings are opening again
00:19:52 --> 00:19:54 and any small telescope will show them.
00:19:54 --> 00:19:57 Avery: Then the Moon gets out of the way. New Moon
00:19:57 --> 00:19:59 is on the 9th in the week either side.
00:19:59 --> 00:20:02 Southern Hemisphere observers can look west
00:20:02 --> 00:20:05 after dusk for the zodiacal light, a faint
00:20:05 --> 00:20:07 cone of sunlight scattered off dust in the
00:20:07 --> 00:20:10 plane of the planets. The south's false dusk
00:20:10 --> 00:20:12 in the north, it's a predawn object in the
00:20:12 --> 00:20:13 east.
00:20:13 --> 00:20:16 Anna: And while it's dark, look up into
00:20:16 --> 00:20:18 Capricornis high overhead from Australia.
00:20:20 --> 00:20:22 That's where Neptune's trailing Trojans are
00:20:22 --> 00:20:25 now, the ones Rubin is finding. You
00:20:25 --> 00:20:27 won't see them, but you'll know where they
00:20:27 --> 00:20:28 are.
00:20:28 --> 00:20:31 Avery: The Leonids peak on the night of the 17th
00:20:31 --> 00:20:34 into the 18th. The first quarter moon sets
00:20:34 --> 00:20:36 around midnight, so the pre dawn hours are
00:20:36 --> 00:20:39 dark. It's a modest shower, 10 to
00:20:39 --> 00:20:42 15 an hour from a dark site and a northern
00:20:42 --> 00:20:42 one.
00:20:43 --> 00:20:46 The radiant is about 70 degrees up at dawn
00:20:46 --> 00:20:48 from the US but only around 23
00:20:48 --> 00:20:51 from Sydney, so expect fewer.
00:20:51 --> 00:20:54 Anna: And the full moon on the 24th is a
00:20:54 --> 00:20:56 supermoon. The first since January.
00:20:57 --> 00:21:00 Avery: A standing remainder. Never look directly
00:21:00 --> 00:21:03 at the sun with your eyes, binoculars or a
00:21:03 --> 00:21:06 telescope unless you're using certified solar
00:21:06 --> 00:21:08 filters that meet the ISO
00:21:08 --> 00:21:10 123122 standard.
00:21:11 --> 00:21:13 That matters when you're hunting Venus close
00:21:13 --> 00:21:16 to sunrise. Stop looking before the sun comes
00:21:16 --> 00:21:16 up.
00:21:16 --> 00:21:19 Anna: That's the show. Two black holes growing
00:21:19 --> 00:21:21 up together behind the dust. A
00:21:21 --> 00:21:24 telescope's last week and another's
00:21:24 --> 00:21:25 request for help.
00:21:26 --> 00:21:29 Trojans at ah, Neptune and Jupiter and
00:21:29 --> 00:21:31 twin satellites at the edge of our magnetic
00:21:31 --> 00:21:32 field.
00:21:32 --> 00:21:34 Avery: If Swift comes down before tomorrow's show,
00:21:34 --> 00:21:36 we'll bring you the time and place as NASA
00:21:36 --> 00:21:38 and Space Force confirm them.
00:21:38 --> 00:21:41 Anna: Show notes, sources and the full blog are
00:21:41 --> 00:21:44 at astronomydaily IO and you can
00:21:44 --> 00:21:46 reach us through the contact form there. Your
00:21:46 --> 00:21:49 questions sent us chasing Swift in the first
00:21:49 --> 00:21:49 place.
00:21:50 --> 00:21:52 Avery: Find us@, uh, astrodailypod on social media.
00:21:53 --> 00:21:54 I'm Avery.
00:21:54 --> 00:21:57 Anna: And I'm Anna. Clear skies
00:21:57 --> 00:21:58 wherever you're looking up from.