Mastodawn

Daniel Fischer 42m ago

More slides about the 2028 Total #SolarEclipse from Terry Cuttle at the SEC - and about coming attractions down under. Relevant websites: https://eclipse.asa.astronomy.org.au/ and https://www.eclipse.aaq.org.au/ 16/n

Marshall Eubanks 29m ago

Matt Willemsen 30m ago

This Map of the Cosmic Web Reaches Back in Time
https://www.universetoday.com/articles/this-map-of-the-cosmic-web-reaches-back-in-time

This Map of the Cosmic Web Reaches Back in Time

The COSMOS scientific collaboration has released the largest map of the Universe ever created. It contains almost 800,000 galaxies, some from the Universe's earliest times. The map challenges some of our ideas about the early Universe.

Universe Today

Marshall Eubanks 19h ago

Matt Willemsen 20h ago

- one is in my wallet, another is in my brain -
The Universe's Missing Black Holes May Have Been Located
https://www.sciencealert.com/the-universes-missing-black-holes-may-have-been-located

The Universe's Missing Black Holes May Have Been Located

For decades, astronomers have theorized that black holes fall into three broad categories.

ScienceAlert

Marshall Eubanks 20h ago

#assassination #Minnesota

AI6YR Ben 22h ago

Walz: "...Melissa Hortman and husband Mark were shot and killed in what appeared to be a politically motivated shooting..."

Marshall Eubanks 1d ago

the ngVLA Prototype Handover Ceremony
https://public.nrao.edu/news/image-release-the-ngvla-prototype-handover-ceremony/

Image Release: the ngVLA Prototype Handover Ceremony - National Radio Astronomy Observatory

mtex antenna technology GmbH officially handed over the prototype antenna for the proposed Next Generation Very Large Array (ngVLA) to the U.S. National Science Foundation National Radio Astronomy Observatory (NSF NRAO) at a ceremony held at the NSF Very Large Array site on the Plains of San Agustin, New Mexico.

National Radio Astronomy Observatory

Marshall Eubanks 1d ago

https://phys.org/news/2025-06-quantum-mechanics-random-demand.html

Michael Slade 1d ago

@TMEubanks This is an excellent way to generate random numbers. I also like the esthetics of this method. https://blog.cloudflare.com/randomness-101-lavarand-in-production/

Randomness 101: LavaRand in Production

There's a wall of lava lamps in the lobby of our San Francisco office. We use it for cryptography. Here's how it works.

The Cloudflare Blog

Marshall Eubanks 1d ago

Quantum mechanics provides truly random numbers on demand

June 11, 2025

At the heart of this service is the NIST-run Bell test, which provides truly random results. This randomness acts as a kind of raw material that the rest of the researchers' setup "refines" into random numbers published by the beacon.

The Bell test measures pairs of "entangled" photons whose properties are correlated even when separated by vast distances. When researchers measure an individual particle, the outcome is random, but the properties of the pair are more correlated than classical physics allows, enabling researchers to verify the randomness. Einstein called this quantum nonlocality "spooky action at a distance."

Quantum mechanics provide truly random numbers on demand

Randomness is incredibly useful. People often draw straws, throw dice or flip coins to make fair choices. Random numbers can enable auditors to make completely unbiased selections. Randomness is also key in security; if a password or code is an unguessable string of numbers, it's harder to crack. Many of our cryptographic systems today use random number generators to produce secure keys.

Phys.org

Marshall Eubanks 2d ago

Bob 🇨🇦🇲🇽🇺🇦2d ago

https://phys.org/news/2025-06-quantum-mechanics-random-demand.html

#science #quantummechanics #mathematics

Quantum mechanics provide truly random numbers on demand

Phys.org

Marshall Eubanks 2d ago

Karly Kingsley 2d ago

In case you’re wondering how wrong what happened to Sen. Padilla was, international news outlets around the world are covering it. That’s how bad it looks.

https://aasnova.org/2024/10/29/testing-cosmology-with-the-dark-energy-survey-five-year-supernova-dataset/
https://www.darkenergysurvey.org/the-des-project/instrument/
3/n

2017 OF201 was discovered from archival data from the Dark Energy Camera Legacy Survey.

The Dark Energy Survey (DES) Collaboration is an international effort to study the properties of dark energy. The DES was conducted using the 4-metre Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile from 2013 to 2019.

The survey used the Dark Energy Camera (DECam) with a wide field of view ~14x the angular size of the Moon.

https://en.wikipedia.org/wiki/Oort_cloud
https://photojournal.jpl.nasa.gov/catalog/PIA17046
4/n

The following graphic illustrates the extent of the orbit of 2017 OF201 within the Solar system, touching the inner region of the Oort Cloud.

The Oort cloud is a vast cloud of icy planetesimals surrounding the Sun at distances ranging from 2,000 to 200,000 AU.

The NASA Voyager 1 spacecraft, launched in 1977, is currently ~167 AU from the Sun.

1 AU = mean Sun-Earth distance ~= 150 million km.

Michael / Chgowiz 🎲🎲May 24

@AkaSci at first, I was imagining that the image showed the potential that our Oort cloud might overlap Alpha Centauri's... then I realized the image scale was kinda logarithmic. :P

@chgowiz @AkaSci Did the same thing! Presume then Alpha Centauri has its own Oort cloud, so does it reach to ours? Do they brush against each other and even exchange objects, or are they still far apart in space's ridiculously vast expanse?

https://en.wikipedia.org/wiki/Alpha_Centauri

@freequaybuoy @chgowiz

That's an interesting question.

The Oort cloud outermost region is ~200,000 AU from the Sun, i.e., 3.2 light-years.

Alpha Centauri is 4.2465 light-years away.

Alpha Centauri has 3 stars: Rigil Kentaurus (α Centauri A), Toliman (α Centauri B), and Proxima Centauri (α Centauri C). A and B are within 35.6 AU. C is 13,000 AU away from AB.

So the question is whether Alpha Centauri has the equivalent of the Oort Cloud.

Alpha Centauri - Wikipedia

@AkaSci @chgowiz Thanks! Yes that's the thing, ours seems to reach over half way, but maybe Alpha Centauri doesn't have one, or it's smaller (something to do with a trinary system's formation? And/or the type of stars), or maybe the cloud is shared, a bit like an electron cloud? I realise, like galaxy mergers, Oort cloud objects might be so far apart even when two merge there aren't actually any, or only very few, collisions.

https://www.astronomy.com/science/ask-astro-does-our-oort-cloud-overlap-with-alpha-centauris/

@AkaSci @chgowiz Ah ha, this is intersting:

"All this is to say that it isn’t clear how close the Oort Cloud actually gets to the Alpha Centauri system, which is about 4.3 light-years away. Even if the Oort Cloud does stretch halfway to the other system, scientists aren’t sure whether it has its own Oort Cloud."

Ask Astro: Does our Oort Cloud overlap with Alpha Centauri’s?

The Oort Cloud begins about 2,000 to 5,000 AU from the Sun and stretches to about 10,000 to 100,000 AU (0.16 to 1.6 light-years), according to NASA. But keep in mind this outer boundary is pretty nebulous, so there is no hard line where the Oort Cloud ends.

Astronomy Magazine

@freequaybuoy @chgowiz
Also, how do the stars in Alpha Centauri affect the objects in our Oort Cloud? The 3 stars have a combined mass more than two times that of our Sun.

@AkaSci @chgowiz Well I think that probably explains comets and other orbital disturbances, eccentricities and anomalies. That article goes on to say, "Likewise, as our nearest celestial neighbor, the Alpha Centauri system likely has some effect, albeit a small one, even at its distance. But Alpha Centauri is actually approaching the Sun. In about 30,000 years, the trio of stars will come within about 2.9 light-years of our star, at which point its influence will be much stronger."

Michael / Chgowiz 🎲🎲May 24

@freequaybuoy So, theoretically, assuming we don't get Great Filtered out, that could happen within the lifespan of the human species... I wonder what having stars within 2.9 ly will do to our Solar System? @AkaSci

@chgowiz @AkaSci Well, if we do make it I'd hope we could nail interstellar travel in that time, at least to our nearest neighbour, if there's a planet worth visiting even colonising, so it would bring it within closer reach to almost the same system or, maybe more likely, our first interstellar war...