Asteroid Flybys, Cosmic Mysteries, and the Search for the Universe's Ghost Signals

In this episode

Today on Astronomy Daily: Japan's Hayabusa2 pulls off a nail-biting high-speed asteroid flyby, James Webb finds the same unexplained chemical mystery on Titan AND Pluto, a neutrino detector may have caught the universe's oldest supernova echo, a wild new theory tries to solve the black hole information paradox, we wrap up the weekend's aurora action, and we look at when NASA's New Horizons might finally cross into interstellar space.
Monday, July 6, 2026 1. Hayabusa2's Flyby of Asteroid Torifune • JAXA's Hayabusa2 spacecraft flew within ~800 metres of near-Earth asteroid (98943) Torifune on July 5, 2026, at a relative speed of about 5.25 km/s (~18,000 km/h). • This is an extended-mission flyby, not a sample return — Hayabusa2 already delivered Ryugu samples to Earth in December 2020. • Purpose: engineering demonstration of high-precision navigation relevant to planetary defense (asteroid deflection technology). • Torifune is roughly 450 metres across. Next stop for Hayabusa2: rendezvous with asteroid 1998 KY26 in 2031. • Source: JAXA/ISAS, Nikkei Asia, phys.org (July 5, 2026). 2. Mystery Molecule Found on Both Titan and Pluto • James Webb Space Telescope data reveals an unexplained absorption feature at ~5.11 micrometres on the surfaces of Titan (Saturn's largest moon) and Pluto. • Evidence points to a surface origin rather than atmospheric origin, based on limb-vs-disc-center comparison on Titan. • Candidate compounds include allenes, but no confirmed identification yet. • Pluto's absorption line is roughly three times broader than Titan's at the same central wavelength. • Study led by Dr. Bruno Bézard's team (Paris Observatory); posted to arXiv June 11, 2026 — not yet peer-reviewed. 3. Super-Kamiokande's Hint of the Diffuse Supernova Neutrino Background • Super-Kamiokande collaboration presented results at Neutrino 2026 (UC Irvine) after analyzing ~5,000 days of data. • Found a statistically significant excess of events between 13.3–81.3 MeV — consistent with the long-predicted Diffuse Supernova Neutrino Background (DSNB). • Significance: 2.6-sigma (~99.5% confidence) — below the 5-sigma discovery threshold, so described as an 'indication,' not a confirmed detection. • If confirmed, DSNB would offer a new way to study the cosmic history of core-collapse supernovae via neutrinos rather than light. 4. A Theoretical Fix for the Black Hole Information Paradox • New theoretical study proposes black holes stop evaporating just before vanishing completely, leaving a stable Planck-scale remnant (~9×10⁻⁴¹ kg). • Mechanism: a repulsive force from spacetime torsion in a 7-dimensional Einstein-Cartan model, active at extreme (Planckian) densities. • Proposal: quantum information is preserved via long-lived 'vibrations' in the remnant's internal torsion field. • This is a theoretical/mathematical proposal, not an observational result. Researchers: Pinčák, Pigazzini, Pudlák, Bartoš. 5. Weekend Geomagnetic Storm / Aurora Wrap-Up • X1.1 solar flare (June 30) and associated CME triggered a G3 (strong) geomagnetic storm around July 3–4, 2026. • Aurora borealis visible as far south as Utah, Colorado, and Nevada in the continental US. • NOAA SWPC reports conditions easing to unsettled/G1 levels through July 6 as CME effects wane. 6. Forecasting New Horizons' Crossing Into Interstellar Space • SwRI researchers (lead: Dr. Jonathan Gasser) combined solar wind forecasting with heliosphere models to predict New Horizons' termination shock crossing. • Forecast window: 2029–2040, with possible multiple crossings as the heliosphere expands/contracts with the solar cycle. • New Horizons is currently ~66 AU from the Sun. Voyager 2 crossed its termination shock at 84 AU in 2007, with a 46% solar wind speed drop. • New Horizons...

Anna: Hello and welcome to Astronomy Daily.

I'm Anna.

Avery: And I'm avery. It's Monday, July 6th,

and we've got a properly stacked show for you

today.

Anna: We're talking a, uh, nail biting asteroid

flyby from Japan. A genuine

cosmic mystery on two different worlds,

and a hint that we might finally be hearing

the universe's oldest ghost signal.

Avery: Plus a black hole theory that could rewrite

the rulebook. A, uh, look back at the

weekend's aurora action, and a very long

range weather forecast for the edge of the

solar system.

Anna: All that right after this.

Avery: Let's kick off in Japan, where Mission

Control had a genuinely nervous Sunday night.

Anna: This is Hayabusa2. Yes, the

same spacecraft that brought samples back

from asteroid Ryugu in 2020. It's

been on an extended mission ever since

because it turned out to have fuel to spare.

Avery: And on July 5, Japan time, it did

something it was never really designed to do.

A high speed flyby of a near Earth asteroid

called Toroph, passing within about

800 meters at, uh, more than 18,000

kilometers an hour.

Anna: 800 meters at that speed.

Jaxa described it like trying to shoot a coin

somewhere between Okinawa and Hokkaido.

Avery: The spacecraft's cameras were never built for

a flyby like this. Hayabusa 2 is a

rendezvous spacecraft designed to hover close

to an asteroid for months, not scream past

one in a heartbeat.

Anna: So this whole encounter is really an

engineering demonstration first, science

second.

Avery: And the reason it matters, beyond the wow

factor, is planetary defense. If

humanity ever needs to nudge a hazardous

asteroid off course, we need to know how

these bodies behave up close. Do they act

like solid rock? Or more like a loose pile of

rubble? That changes everything about how

you'd deflect one.

Anna: JAXA confirmed the spacecraft is healthy.

The flyby went to plan, and cameras captured

imagery of Torophone's shape, texture and

temperature that scientists are poring over

now.

Avery: Torophone itself is only about 450

meters across. No sample returned this

time. This one's, uh, a look and go.

Hayabusa2's next big date is

2031, when it rendezvous with a

completely different target, the small, fast

spinning asteroid 1998

KY26.

Anna: So think of Sunday as a dress rehearsal. A

spacecraft already passed its day job, still

finding ways to be useful.

Avery: Our next story is one of those lovely we

genuinely don't know what this is moments in

astronomy.

Anna: Researchers combing through James Webb Space

Telescope data have found an unexplained

absorption feature, basically a dick in the

light spectrum, sitting at exactly

5.11 micrometers uh, and

Avery: they found it twice. Once on Saturn's big

moon, Titan, and

Anna: once on Pluto, which is odd, because

Titan and Pluto are about as different as

two icy worlds get. Titan has a thick

nitrogen methane atmosphere, methane

lakes, actual rain. Pluto has a

wisp of an atmosphere and is bitterly cold

and airbound in name only.

Avery: The team led by Bruno Bizard at the Paris

Observatory checked whether the signal could

just be coming from the atmosphere rather

than the surface. And on Titan at least, the

absorption was actually weaker at the edge of

the disk, where you'd expect an atmospheric

signal to be stronger that points to the

surface as the source.

Anna: They've ruled out the usual common

ices, straightforward hydrocarbons, the

nitrogen photochemistry products you'd

expect. The closest match so far is a class

of molecules called Allenes, but it's not

confirmed.

Avery: And, and here's the twist.

Anna: On Pluto, the same absorption line is

about three times broader than on Titan,

even though it sits at the same wavelength.

So whatever it is, it's behaving differently

on each world.

Avery: This result is still a preprint, so it hasn't

cleared peer review yet. But the researchers

are calling it one of the more compelling,

unassigned features they've seen. Solve this

one, and you learned something new about

organic chemistry happening in the deep

freeze on two worlds at once.

Next story three takes us underground,

literally, to the Super Kamikande Neutrino

Detector in Japan.

Anna: Every second, somewhere in the universe, a

massive star reaches the end of its life and

collapses into a supernova. Each one of those

explosions flood space with neutrinos,

ghostly particles that barely interact with

anything.

Avery: Physicists have long predicted that all of

those neutrinos from every supernova across

the entire history of the universe should add

up to a very faint, constant background

hum. The diffuse supernova neutrino

background, or DSNB, for short.

Anna: It's never been detected until

maybe now. The Super Kamikande

collaboration presented results this week at

the Neutrino 2026 conference in

California. After combing through nearly

5,000 days, that's about 13 and a

half years of data.

Avery: They found a statistically significant excess

of events in the expected energy range. The

confidence level works out to about

Anna: 99.5%, which sounds

enormous, but in particle physics terms, it's

still short of the gold standard five sigma

threshold needed to call it a discovery. So

the team is very deliberately calling this an

indication, not a confirmation.

Avery: Still, if it holds up with more data, this

would be a whole new way of studying the

history of the universe's. Supernovae. Using

particles instead of light, it could tell us

how often massive stars have exploded over

cosmic time and how black holes and neutron

stars formed a background

Anna: hum from every dying star that ever

lived.

Not bad for a Monday Sticking with

Avery: big theoretical ideas, Story four is

a fresh attempt to solve one of physics's

most stubborn headachesthe Black Hole

Information paradox.

Anna: Quick Refresher Stephen Hawking showed in the

1970s that black holes very

slowly radiate energy and in theory

eventually evaporate completely. The

paradox is what happens to all the

information about everything that ever fell

in. Quantum mechanics says information

can't just vanish, so where does it go?

Avery: A new theoretical study proposes an answer

using a seven dimensional model of spacetime

built on something called Einstein Cartan

geometry with torsion basically letting

spacetime twist as well as bending.

Anna: The researchers found at extreme densities

right at the Planck scale, that twisting

produces a, uh, repulsive force strong enough

to halt the final stage of Hawking in

operation completely.

Avery: Instead of vanishing, the black hole would

freeze into a stable leftover object,

a remnant with a predicted mass of around

9 times 10 to the -41

kilograms. Genuinely tiny.

Anna: And the proposal is that this remnant acts

like a permanent archive with the black

hole's information encoded in long lived

internal vibrations. Rather than being lost,

it's squarely in

Avery: fascinating but far from settled territory.

This is a theoretical framework, not an

observation, but it's a serious attempt to

answer a 50 year old question. And it comes

with a neat bonus. The same geometry might

also help explain why fundamental particles

have, uh, uh, mass in the first place.

Anna: Two birds, one seven dimensional stone

Next up, a quick check in on the sky show

from the weekend for anyone who missed it or

is still out chasing it.

Avery: Saturday's X1 solar flare and its

coronal mass ejection slammed into Earth's

magnetic field as forecast, pushing

geomagnetic activity up to G3.

Strong storm levels through July 3rd and 4th.

Anna: Aurora Borealis was reported as far south

as Utah, Colorado and Nevada in the US

with some lovely July 4th fireworks and

Aurora combo shots doing the rounds online.

Avery: NOAA AH Space Weather Prediction center says

activity has been easing since with

conditions dropping to unsettled to G1 levels

through today the 6th as the effects of last

week's CMEs fade out.

Anna: So if you're in a high latitude spot,

Southern Hemisphere included, tonight's still

worth a glance skyward. But don't expect a

repeat of Saturday's fireworks. The main

event has passed.

Avery: Our last story is a lovely bit of long

range Weather forecasting Except the weather

is solar wind and the destination is

interstellar space.

Anna: NASA's New Horizons, the

spacecraft that gave us our first close up

look at Pluto in 2015 and then

flew past the Kuiper Belt object Arrokoth

in 2019, is still out there, still

working currently around, uh, 66

astronomical units from M the Sun.

Avery: Researchers at the Southwest Research

Institute, led by Dr. Jonathan Gasser

have combined solar wind forecasting with

helios heliosphere models to predict when New

Horizons will cross. Determination Shock the

first plasma boundary marking the edge of the

Sun's influence before the true edge of the

heliosphere further out.

Anna: Their answer? Somewhere between

2029 and 2040, which

is, let's be honest, a pretty wide window.

Avery: But that's because the heliosphere isn't a

fixed shell. It swells and shrinks with the

solar cycle, expanding during solar maximum

and contracting during solar minimum. New

Horizons might even cross the boundary more

than once if the shock front M moves back and

forth across the spacecraft's path.

Anna: For context, Voyager 2 crossed its

termination shock back in 2007

at 84 astronomical units and

measured a sharp 46% drop

in solar wind speed right at the boundary.

Avery: If New Horizons gets there, it'll become only

the third spacecraft in history to cross into

that outer frontier after Voyager 1 and

2. Not bad for a mission that was just

supposed to visit Pluto.

Anna: A whole new frontier. And we might get to

watch it happen live sometime in the next

decade or so.

Avery: And that's a wrap on Today's episode.

An asteroid 5i a, uh, shared mystery on

two icy worlds, a possible whisper from

every supernova that ever happened, a

theoretical black hole afterlife, some

leftover aurora, and a decade long forecast

for the edge of the solar system.

Anna: If you enjoyed the show, please do leave us a

rating and review. It genuinely helps other

space fans find us.

Avery: I'm Avery.

Anna: And I'm Ana. We'll see you next time on

Astronomy Daily. Clear skies, everyone.

Avery: Sam