Notices by AkaSci 🛰️ (akasci@fosstodon.org), page 3

Here are some fascinating illustrations from the paper modeling the bow shock, the gas flow, the wake and the blueshift and redshift of light from different regions of the bow of the Runaway Supermassive Black Hole RBH-1.

At z=0.96, RBH-1 is ~7.8 billion ly away.

"These results confirm that the wake is powered by a supersonic runaway supermassive black hole, a long-predicted consequence of gravitational-wave recoil or multi-body ejection from galactic nuclei."

https://arxiv.org/pdf/2512.04166
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One possible explanation for the Runaway SMBH -

First, 2 galaxies merge creating a binary SMBH (1,2).

A 3rd galaxy comes in (3), its SMBH sinks to the center of the merger (>1 Gyr), leading to a 3-body interaction (4).

The lightest BH becomes unbound from the other two and receives a large velocity kick (~40 Myr ago). The remaining binary gets a smaller velocity kick in the opposite direction. If the kicks are large enough, all SMBHs can leave the galaxy (5).

https://iopscience.iop.org/article/10.3847/2041-8213/acba86#apjlacba86f7
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The curious linear feature, containing a 200,000-light-year-long chain of young blue stars, was first observed by the researchers using the Hubble Space Telescope in 2023.

The front edge of the trail had a remarkably bright knot of ionized oxygen. Researchers believed that circumgalactic gas was being shocked and heated from the motion of the black hole hitting the gas, or it could be radiation from an accretion disk around the black hole.

https://science.nasa.gov/missions/hubble/hubble-sees-possible-runaway-black-hole-creating-a-trail-of-stars/
https://iopscience.iop.org/article/10.3847/2041-8213/acba86#apjlacba86f7
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Researchers, using the JWST, have confirmed that a black hole, first detected in 2023 by the same team, is indeed a supersonic Runaway Supermassive Black Hole, ejected by and racing away from its host galaxy at 3.43 million km/h 😮

RBH-1 contains ~20 million solar masses and has left behind a 200,000-light-year-long "contrail" of newborn stars, twice the diameter of our Milky Way galaxy, as it plows ahead into the circumgalactic medium (CGM).

https://arxiv.org/pdf/2512.04166
https://science.nasa.gov/missions/hubble/hubble-sees-possible-runaway-black-hole-creating-a-trail-of-stars/
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The canned 60 minutes CECOT Segment was aired on Canada’s Global TV app and is now available for viewing at various Internet sites.

Here's one. We can see why the administration and its lackeys at CBS did not want the world to see it.

https://www.muellershewrote.com/p/watch-the-60-minutes-cecot-segment
#UsPol
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An analemma is a plot of the position of the Sun as viewed from a fixed position on Earth at the same clock time every day for an entire year.

The lowest point of the analemma occurs close to the winter solstice in the northern hemisphere.

http://www.star.ucl.ac.uk/~apod/apod/ap130922.html
https://en.wikipedia.org/wiki/Analemma
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The next (northern hemisphere) winter solstice on Mars will occur on April 25, 2026.

The axial tilt of Mars at 25.2° is close to that of Earth. The tilt causes seasons similar to earth.
A year on Mars is 687 Earth days long.
Seasons are not of equal length on Mars due to its orbital eccentricity.
The New Year starts on the day of the Spring Equinox.
Year 1 was designated to start on Apr 11, 1955.
This is year 38.

https://www.planetary.org/articles/mars-calendar
https://www.instagram.com/popular/james-o%27donoghue/
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This image of Earth posted by ESA was taken by the Meteosat MTG‑I1 weather satellite 2 days ago on 19 December 2025 at 06:00 GMT. It vividly shows Earth’s day–night terminator line tilted near its annual maximum of about 23.5°.

MTG-I1 (Meteosat Third Generation Imager-1) is located in a geostationary orbit (35,786 kilometers) at 0 degrees longitude, directly above the Prime Meridian.

https://bsky.app/profile/esa.int/post/3maimej6le22v
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Below are images of Earth taken 6 days ago (Dec 21, 2025) and on June 19, 2025 near the last Summer Solstice, from the direction of the Sun.

The tilt of earth's axis at these two extreme points can be seen clearly.

These images were taken by the NASA DSCOVR satellite, which is located 1.5 million km away at the Sun-Earth L1 Lagrange point.

https://epic.gsfc.nasa.gov/?date=2025-12-15
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Beautiful pic of the sunset at Stonehenge taken on December 20, 2025.

"There, through stones precisely placed 4,500 years ago, a 4.5 billion year old large glowing orb is seen setting.

Even given the precession of the Earth's rotational axis over the millennia, the Sun continues to set over Stonehenge in an astronomically significant way."

https://apod.nasa.gov/apod/ap251222.html
Image Credit & Copyright: English Heritage, Josh Dury
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Also, see https://fosstodon.org/@AkaSci/115688248995273358 for
why the date of the earliest sunset of the year does not coincide with the winter solstice.
@rozeboosje
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Scoop by Michael M. Grynbaum at the NYT on the abrupt removal of the “60 Minutes” segment on El Salvador’s megaprison CECOT. The segment was cancelled/postponed by Bari Weiss, the new editor in chief of CBS News.

60 Minutes" correspondent Sharyn Alfonsi tells colleagues that CBS's decision to pull her segment tonight "is not an editorial decision, it is a political one."

https://www.nytimes.com/2025/12/21/business/60-minutes-trump-bari-weiss.html
#UsPol
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Here is a copy of an email from Sharyn Alfonsi, the veteran “60 Minutes” correspondent who reported the segment, to her ‘60 Minutes’ colleagues, posted by Michael M. Grynbaum on X.

"If the administration’s refusal to participate becomes a valid reason to spike a story, we have effectively handed them a ‘kill switch’ for any reporting they find inconvenient."

"I care too much about this broadcast to watch it be dismantled without a fight."

#UsPol
2/n

Babies in the randomized, controlled trial in Guinea-Bissau will or will not receive the hepatitis B vaccine at birth.

It is a major breach of scientific ethics to withhold an intervention that has been proven safe and effective - Paul Offit.

The study does not appear to be looking at whether the vaccine is more effective at birth, it will look for “overall health effects".

About 18% of Bissau-Guinean adults and 11.2% of toddlers are infected with the virus.

https://www.theguardian.com/society/2025/dec/19/hepatitis-b-vaccine-study-guinea-bissau-rfk
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"From beginning to end, 2025 was a year of devastation for scientists in the United States.

Pipeline of new scientists cut off
Fewer people trained to treat addiction
Communities left to brave extreme weather alone
LGBTQ+ people made invisible
Pediatric brain cancer research squelched
Inequality in science festers"

Let's redouble our efforts in 2026 to throw these hyenas out.

https://theconversation.com/this-year-nearly-broke-me-as-a-scientist-us-researchers-reflect-on-how-2025s-science-cuts-have-changed-their-lives-271282
#UsPol #Science
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Happy Winter Solstice, which will occur at 15:03 UTC (10:03 a.m. EST) today.

Today, earth's axis, which is currently tilted 23.44° from the plane of its orbit around the Sun (the ecliptic), will point away from the Sun.

It is the shortest day of the year in the northern hemisphere; which means that days will keep getting longer starting tomorrow 🥳

https://earthsky.org/astronomy-essentials/everything-you-need-to-know-december-solstice/
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"The administration inserted a photo of Bill Clinton, Michael Jackson, and Diana Ross into the Epstein files and falsely implied it showed them with victims.

In reality, it’s a publicly available fundraiser photo featuring Jackson and Ross’s own children."

https://bsky.app/profile/meidastouch.com/post/3mag7myutmc2d
#UsPol
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I missed this post from LeoLabs on Dec 18, where they noted that 10s of debris objects were detected from the Starlink 35956 anomaly event of 17 Dec 2025.

They also assessed that the satellite’s initial drop in orbital altitude was likely caused by an internal energetic source (e.g., an explosion) rather than a collision with space debris or another object.

Ed Lu of LeoLabs posted today 100s of debris objects being tracked.

No info on fragment sizes or apogee.

No new word from SpaceX.
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Starlink anomaly at 418 km altitude - loss of comms, venting of the propulsion tank, rapid decay in orbit by ~4 km, and the release of a small number of trackable low relative velocity objects.

Starlink states that there is no risk to the ISS (422.7 - 427.0 km orbit) from the largely intact tumbling satellite which will reenter the atmosphere in a few weeks.

No info on root cause. An explosion? Collision? What about any untrackable debris? Risk to other satellites?

@sundogplanets
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Interesting paper explores the question - "Can LLMs actually discover science, or are they just good at talking about it?"

Good summary in a thread by Alex Prompter on twitter.

https://arxiv.org/abs/2512.15567
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