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kottke.org posts about astronomy

The New Vera C. Rubin Observatory Is a Firehose of Astronomical Imagery & Data

closeup of a brightly colored nebula

image of many stars and galaxies

The Vera C. Rubin Observatory in Chile is operational and will soon embark on its primary mission: to take a detailed image of the sky every night for the next ten years.

A powerful new observatory has unveiled its first images to the public, showing off what it can do as it gets ready to start its main mission: making a vivid time-lapse video of the night sky that will let astronomers study all the cosmic events that occur over ten years.

“As the saying goes, a picture is worth a thousand words. But a snapshot doesn’t tell the whole story. And what astronomy has given us mostly so far are just snapshots,” says Yusra AlSayyad, a Princeton University researcher who oversees image processing for the Vera C. Rubin Observatory.

“The sky and the world aren’t static,” she points out. “There’s asteroids zipping by, supernovae exploding.”

And the Vera C. Rubin Observatory, conceived nearly 30 years ago, is designed to capture all of it.

These images will revolutionize how astronomy is done:

Astronomy is following in the path of scientific fields like biology, which today is awash in DNA sequences, and particle physics, in which scientists must sift through torrents of debris from particle collisions to tease out hints of something new.

“We produce lots of data for everyone,” said William O’Mullane, the associate director for data management at the observatory. “So this idea of coming to the telescope and making your observation doesn’t exist, right? Your observation was made already. You just have to find it.”

“Your observation was made already. You just have to find it.” I love that.

The Rubin team has released some images from the telescope’s initial run, to inform the public of what the project is capable of. In less than a half-day’s operation, the Rubin discovered 2,104 new asteroids in our solar system.

In about 10 hours of observations, NSF-DOE Vera C. Rubin Observatory discovered 2104 never-before-seen asteroids in our Solar System, including seven near-Earth asteroids (which pose no danger). Annually, about 20,000 asteroids are discovered in total by all other ground and space-based observatories. Rubin Observatory alone will discover millions of new asteroids within the first two years of the Legacy Survey of Space and Time. Rubin will also be the most effective observatory at spotting interstellar objects passing through the Solar System.

Not bad, rook. The team has set up a dedicated image viewer for their massive images.

closeup of a brightly colored nebula

image of many stars and galaxies

You can read more about the Rubin at The Atlantic, The Rubin Observatory Is a Cosmic Cathedral, written by Michael Jones McKean, the observatory’s artist in residence:

Rubin is also a rare scientific megaproject that feels excitingly relatable. Instruments such as particle accelerators, neutrino detectors, and even radio telescopes might command our awe, but they roam in realms far outside sensorial experience. At its core, Rubin is an optical telescope. This links it to a long continuum of prosthetic tools that help our bodies better do what they already do naturally — see and process light.

And a trio of videos on how the observatory works from BBC News, New Scientist, and astrophysicist Becky Smethurst.

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Astronaut Don Pettit’s Marvelous Photos From Space

a photo taken from the ISS with the Milky Way visible over an intensely colored sunrise

The NY Times has a nice feature on NASA astronaut Don Pettit’s photography from his latest stay in space, a 220-day mission aboard the ISS.

Now, you know I like a good astronomical image (like the one above of an ISS sunrise), but the thing that really caught my eye was the video of Pettit’s experiment involving charged water droplets and a teflon needle:

I could watch that allllll day long.

More Pettit: Swirling Green Aurora Captured From the ISS.

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Swirling Green Aurora Captured From the ISS

I don’t have a whole lot to say about this video except wow. Wow wow. It’s almost inconceivable that we live in a world of sights like this. Feels like science fiction but is actually real. Captured by NASA astronaut Don Pettit aboard the ISS.

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Theoretical Gravastars Are Even Weirder Than Black Holes

TIL I learned about gravastars (aka a gravitational vacuum star), theoretical objects related to black holes. Both are massive & dense, but instead of a singularity surrounded by an event horizon, gravastars are made up of dark energy surrounded by a extremely thin shell of exotic matter.

The shell of the gravastar is utterly dark and the coldest thing in the universe, only a billionth of a degree above absolute zero. If we look at it in deep infrared, even the cosmic microwave background glows bright in comparison. It is made from an entirely new, unique and extreme matter that is at the very limit of what is physically possible in nature and doesn’t have a name yet. Actually, the shell is so incredibly thin that atoms seem truly gigantic next to it.

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The 35th Anniversary of the Hubble Space Telescope

the Eagle Nebula

the Sombrero galaxy

the Large Magellanic Cloud

The Hubble Space Telescope was launched into space 35 years ago and in celebration of that milestone, Alan Taylor collected some recent images from the Hubble, whose mission is still ongoing.

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Swamped Skies

a photo of a night sky with dozens of satellite trails

Photographer Joshua Rozells on his photo of our increasingly crowded night skies:

The light pollution caused by satellites is quickly becoming a growing problem for astronomers. In 2021, over 1700 spacecrafts and satellites were put into orbit. Light pollution caused by SpaceX’s Starlink satellites are the worst offenders because they are low Earth orbit satellites, and they travel in satellite trains. One can only assume the issue will exponentially increase in the next few years, with SpaceX alone intending to launch over 40,000 satellites in total. The space industry is almost entirely unregulated, with no limits on the amount of satellites that anyone is able to launch and there is currently no regulation in place to minimise the light pollution they cause.

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What Did Hubble See on Your Birthday?

the Egg Nebula as imaged by the Hubble Space Telescope, colorful ripples emanate outward into space

The Hubble Space Telescope “has observed some fascinating cosmic wonder every day of the year, including on your birthday”. Just enter your month and day of birth to find out what it saw. My birthday image is of the Egg Nebula (shown above):

Where is the center of the Egg Nebula? Like a baby chick pecking its way out of an egg, the star in the center of the Egg Nebula is casting away shells of gas and dust as it slowly transforms itself into a white dwarf star.

The Egg Nebula is a rapidly evolving pre-planetary nebula spanning about one light year toward the constellation of Cygnus. Thick dust blocks the center star from view, while the dust shells further out reflect light from this star. Light vibrating in the plane defined by each dust grain, the central star and the observer is preferentially reflected, causing an effect known as polarization. Measuring the orientation of the polarized light for the Egg Nebula gives clues as to location of the hidden source. The above image taken by the Advanced Camera for Surveys on the Hubble Space Telescope is false-color coded to highlight the orientation of polarization.

Cool! I like my birthday nebula. (via the morning news)

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Comets Are Cool

the long tail of a comet stretches over an observatory just after sunset

From astronomer Yuri Beletsky, a photo of Comet C/2024 G3 (ATLAS) arching over ESO’s Paranal Observatory in Chile.

Unfortunately, it seems like the comet disintegrated as it swooped around the Sun, always a danger.

The nucleus of Comet ATLAS (C/2024 G3) held together during a brutal perihelion but not for long. Lionel Majzik of Hungary was the first to report and record dramatic changes in the comet between January 18th and 19th. The bright, strongly condensed head rapidly became more diffuse, a sure sign that its nucleus was disintegrating based on past observations of crumbling comets. His superb sequence, photographed remotely from Chile, clearly reveal the dramatic transformation, which was later confirmed by Australian observers.

The tail will be visible for a few days after the breakup — such comets are called “headless wonders” by astronomers. (via @philplait.bsky.social)

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Check Out the 2025 Moon Phases

NASA’s Goddard Space Flight Center has released a pair of visualizations of the phases the Moon will go through in 2025, one for the northern hemisphere above and one for the southern hemisphere below:

Look at that sucker wobble! Each frame of the 4K video represents one hour and there are lots of locations labeled on the map, including the landing sites of the Apollo missions.

But also: How have I never noticed that the Moon is upside-down in the southern hemisphere?! I mean, it makes total sense but I’ve just never noticed or thought it through. 🤯 (via the kid should see this)

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JW Space Telescope Discovers Aliens!

the famous pillars of creation astronomical objects with googly eyes on them

I know astronomical imagery is on the verge of being over-processed these days (those colors don’t exist out there!), but this image from the JWST is shocking. Clear evidence of Sesame Street’s Yip Yip Martians from billions of years ago. What did Jim Henson know and when did he know it?

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Gobsmacking Image of a Stellar Nursery

A star cluster is shown inside a large nebula of many-coloured gas and dust. The material forms dark ridges and peaks of gas and dust surrounding the cluster, lit on the inner side, while layers of diffuse, translucent clouds blanket over them. Around and within the gas, a huge number of distant galaxies can be seen, some quite large, as well as a few stars nearer to us which are very large and bright.

Wow, check out this just-released image from the JWST team of star cluster NGC 602.

The local environment of this cluster is a close analogue of what existed in the early Universe, with very low abundances of elements heavier than hydrogen and helium. The existence of dark clouds of dense dust and the fact that the cluster is rich in ionised gas also suggest the presence of ongoing star formation processes. This cluster provides a valuable opportunity to examine star formation scenarios under dramatically different conditions from those in the solar neighbourhood.

It is very worth your time to click through and look at this image in all of its massive celestial glory. I found this image via Phil Plait, who calls it “one of the most jaw-droppingly mind stomping images I’ve seen from JWST” and, directing us back to the science (remember the science?!), notes that NGC 602 is actively forming stars (it’s only about 5 million years old) and that it depicts “the first young brown dwarfs outside our Milky Way”. Cool!

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Infinite Cosmos: Visions From the JW Space Telescope

book cover for Infinite Cosmos

Out today from National Geographic is Infinite Cosmos, a gorgeous-looking book by Ethan Siegel (intro by Brian Greene). It’s about the history of the JWST, humanity’s biggest ever space telescope, a machine that allows us to peer deeper & clearer into the universe than ever before, and some of the amazing results obtained through its use.

page spread of Infinite Cosmos showing the swirling Phantom Galaxy

Siegel wrote a piece about the book for Big Think, which includes an excerpt. Gravitational lensing is so cool:

Even with its unprecedented capabilities, JWST’s views of the universe are still finite and limited. The faintest, most distant objects in the cosmos — including the very first stars of all — remain invisible even in the longest-exposure JWST images acquired to date. The universe itself offers a natural enhancement, however, that can reveal features that would otherwise remain unobservable: gravitational lensing.

Whenever a large amount of mass gathers together in one location, it bends and distorts the fabric of the surrounding space-time, just as the theory of general relativity dictates. As light from background objects even farther away passes close to or through that region of the universe, it not only gets distorted but also gets magnified and potentially bent, either into multiple images or into a complete or partial ring. The foreground mass behaves as a gravitational lens. The amount of mass and how it’s distributed affect the light passing through it, amplifying the light coming from those background sources.

page spread of Infinite Cosmos showing how JWST images are colored

page spread of Infinite Cosmos showing the table of contents overlaid on an image of the JWST mirrors

Infinite Cosmos is available for purchase at Amazon and Bookshop.

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Astronomy Photographer of the Year for 2024

photo of the ISS transiting the Sun

comparision of maximum solar activity with minimum solar activity

several stacked images of the Sun during an annular eclipse

the Milky Way stretches across the sky

Royal Museums Greenwich has announced the winners of the Astronomy Photographer of the Year 2024 competition. You can also check out some of the shortlist entries and runners-up in each category (Moon, Sun, etc.)

Photos above by (from top to bottom): Tom Williams, Peter Ward, Ryan Imperio, and Tom Rae.

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Incredible Time Lapse Movies of Exoplanets

Ok, I did not know this, and it’s blowing my mind: we have been imaging exoplanets for such a long time that scientists have made time lapse movies of their motion around their stars. This one is a 12-year time lapse of four planets orbiting a star called HR 8799 (images from 2009-2021):

And this one of Beta Pictoris b covers a time period of 17 years (2003-2020):

HR 8799 is 133.3 light-years away from Earth and Beta Pictoris is 63.4 light-years away. That’s amazing! (via @philplait.bsky.social)

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The Sky Was Purple and Red and Yellow and On Fire

a photo of the aurora borealis above windmills

a photo of the aurora borealis above some mountains

There was a big solar storm this weekend and photos of the aurora borealis took over social media; it was delightful. For round-ups, check out the NY Times, the Guardian, @itsjackcohen, PBS NewsHour, Spaceweather.com, Forbes, and MSN.

The photos above are by Albert Dros and Sean O’ Riordan (prints here). O’ Riordan took his shot in Tasmania and actually had to tone it down for publication:

When the clouds are glowing red you know something is off the charts, I tried my best to desaturate this and make it look some bit like a photo and not a science fiction scene!

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The Longest Total Solar Eclipse Ever (73 Minutes!)

Ok, I said no more eclipse posts (maybe) and then posted like two or three more, but really this is the last one — maybe! In 1973, a group of scientists witnessed the longest ever total solar eclipse by flying in the shadow (umbra) of the moon in a Concorde prototype for 74 minutes over the Sahara desert. From the abstract of a paper in Nature about the flight:

On June 30, 1973, Concorde 001 intercepted the path of a solar eclipse over North Africa, Flying at Mach 2.05 the aircraft provided seven observers from France, Britain and the United States with 74 min of totality bounded by extended second (7 min) and third (12 min) contacts. The former permitted searches for time variations of much longer period than previously possible and the latter provided an opportunity for chromospheric observations of improved height resolution. The altitude, which varied between 16,200 and 17,700 m, freed the observations from the usual weather problems and greatly reduced atmospheric absorption and sky noise in regions of the infrared.

Mach 2.05 = 1573 mph = 2531 km/h. 17,700 m = 58,000 ft. They added portholes to the roof of the plane for better viewing and data gathering. This page on Xavier Jubier’s site contains lots of amazing details about the flight, including a map of the flight’s path compared to the umbra, photos of the retrofitted plane, and a graph of the umbra’s velocity across the surface of the Earth (which shows that for at least part of the eclipse, the Concorde was actually outrunning the moon’s shadow).

By flying inside the umbral shadow cone of the Moon at the same speed, the Concorde was going to stay in the darkness for nearly 74 minutes, the time for astronomers and physicists on board to do all the experiences they could imagine to complete during this incredible period of black Sun. They were able to achieve in one hour and fifteen minutes what would have taken decades by observing fifteen total solar eclipses from places that would have not necessarily gotten clear skies.

And finally, here’s a 30-minute French documentary from 1973 about the eclipse flight.

So. Cool!

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What Are the Odds?

photograph of a total eclipse, showing the solar prominences around the edge

Ok, one last post about the total solar eclipse and then I’m done talking about it. (Maybe.)

There are so many mind-blowing things about eclipses but the one I can’t stop thinking about is the nearly impossible coincidence that the sun and the moon are the same relative size in the sky. If the moon were a little bit smaller or farther away, we wouldn’t have total eclipses where you can look directly at the sun, see the corona, the sky goes dark, you see a sunset effect all around the horizon, etc. That is some spooky magical shit. Ted Underwood put it this way:

Random accident that the moon and sun are the same apparent size here. If we had interstellar tourism, this is the One Thing that everyone would know about the Earth, and when they visited they wouldn’t want to see anything else. “We also have museums?” we’d say.

The moon is slowly drifting away from the Earth and total eclipses will gradually get rarer and rarer until, hundreds of millions of years from now, they will stop completely.1 That we’re all here right now, getting to experience this magical thing? Like, what?! If a science fiction writer made this up for a story, we’d say it’s too much.

And yet, for me at least, the coincidences don’t stop there.

When I saw my first total eclipse in 2017, we had to drive for 3.5 hours through three different rainstorms to find some clear skies. When we finally stopped, 40 minutes before totality, it was in a town so small that it’s not even called a town anymore: Rayville, Missouri. Yep, we found the sun in Rayville. What are the odds?

And then this year, on April 8th, the path of totality went right over my house in Vermont. In the past 70 years in Vermont prior to 2024, it’s been overcast about 50% of the time and only mostly sunny in 13 of those years. This year? Not a cloud in the sky when I woke up Monday morning.

I watched with a group of people in a big field in Colchester, including my friend Caroline and her dog, Stella (a name derived from the Latin word for star). There were a bunch of other groups watching in the field too and after totality had thrilled us all, they trickled back to their cars and homes. Our group stayed and I watched the last little bit of the moon slip past the sun through my telescope — it was officially over.

A large nearby group of folks with a couple of dogs left shortly after that. One of the dogs came over for a sniff and one of our party asked the guy what the dog’s name was. “Luna.”

And then Luna departed.

Seriously, what are the odds?

Eclipse photo above taken by my friend Mouser, with whom I witnessed the 2017 eclipse. It’s worth looking at large.

  1. I am sure, hundreds of millions of years ago, when the moon was closer to the Earth, total eclipses were a whole other level of whoaaaaa — lasting for 10-20 minutes at a time, completely blocking out any light from the sun, total darkness all around, etc.
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The Best Photos and Videos of the 2024 Solar Eclipse

Well, the total solar eclipse was once again completely awesome. I didn’t have to go chasing all over tarnation this time, the telescope worked out amazingly well, and I got to share it with a bunch of first-timers, both in-person and via text. I’m going to share some thoughts, photos, and videos from others around the internet in an even bloggier fashion than usual. Here we go.

My pal Noah Kalina got one of my favorite shots of the day (see also + prints are available):

Solar Eclipse 2024 01

Gobsmacking shot from Rami Ammoun…it’s a blend of multiple exposures so you can see the sun and moon at the same time. Love this shot.

Solar Eclipse 2024 02

And another stunner from Andrew McCarthy:

Solar Eclipse 2024 09

Ryan Cox got some great shots of the solar prominences during totality.

Solar Eclipse 2024 03

Quick solar prominence explainer interlude: if you had a clear look at totality, you may have noticed some orange bits poking out around the moon. NASA: What is a solar prominence?

A solar prominence (also known as a filament when viewed against the solar disk) is a large, bright feature extending outward from the Sun’s surface. Prominences are anchored to the Sun’s surface in the photosphere, and extend outwards into the Sun’s hot outer atmosphere, called the corona. A prominence forms over timescales of about a day, and stable prominences may persist in the corona for several months, looping hundreds of thousands of miles into space. Scientists are still researching how and why prominences are formed.

The red-glowing looped material is plasma, a hot gas comprised of electrically charged hydrogen and helium. The prominence plasma flows along a tangled and twisted structure of magnetic fields generated by the sun’s internal dynamo. An erupting prominence occurs when such a structure becomes unstable and bursts outward, releasing the plasma.

A timelapse video of totality from Scientific American:

Thomas Fuchs caught some sunspots through his telescope during the partial eclipse. (We saw these through our ‘scope as well.)

Solar Eclipse 2024 04

Quick sunspot explainer interlude. NASA: What exactly is a sunspot?

A sunspot is simply a region on the surface of the sun-called the photosphere-that is temporarily cool and dark compared to surrounding regions. Solar measurements reveal that the average surface temperature of the sun is 6000° Celsius and that sunspots are about 1500° Celsius cooler than the area surrounding them (still very hot), and can last anywhere from a few hours to a few months. Sunspots expand and contract as they move across the surface of the sun and can be as large as 80,000 km in diameter.

Sunspots are magnetic regions on the sun with magnetic field strengths thousands of times stronger than the Earth’s magnetic field, and often appear in pairs that are aligned in an east-west direction. One set will have a positive or north magnetic field while the other set will have a negative or south magnetic field. The field is strongest in the darker parts of the sunspots — called the umbra. The field is weaker and more horizontal in the lighter part-the penumbra. Overall, sunspots have a magnetic field that is about 1000 times stronger than the surrounding photosphere.

This Instagram account has a lovingly assembled collection of solar eclipse stamps from around the world (Aruba, Bhutan, Chile, Romania, Kenya, and even North Korea).

Solar Eclipse 2024 05

A NY Times timelapse: See the Total Solar Eclipse’s Shadow From Space (assembled from NASA and NOAA satellite imagery).

Great solar prominences on this shot from Notorious RBMK. Wow:

Solar Eclipse 2024 06

A timelapse video from Ariel Waldman of totality in Mazatlán. You really get a sense of the eclipse as a passing shadow from this.

Incredible “tiny planet” panorama timelapse by Matt Biddulph. Here’s a still frame during totality:

Solar Eclipse 2024 07

The 8 types of eclipse photo from XKCD.

Solar Eclipse 2024 08

The view of the eclipse from the International Space Station.

More photos from The Dammich, fotoelliott, max GORDON, good thread of photos, and photo round-ups from PetaPixel, New Scientist, BBC Science Focus, Mashable, Associated Press, and Wired.

Video from Nate Luebbe of the moment of totality, with Baily’s beads and solar prominences.

This is a fake. Super super cool looking, but a fake. (Update: not quite a fake, just a really badly enhanced version of this composite HDR photo.) And I’m not sure I entirely trust the veracity of the trending search results for “why do my eyes hurt” but here it is anyway.

Earth Will Have Its Last Total Solar Eclipse in About 600 Million Years:

Total solar eclipses occur because the moon and the sun have the same apparent size in Earth’s sky — the sun is about 400 times wider than the moon, but the moon is about 400 times closer.

But the moon is slowly moving away from Earth by about 1-1/2 inches (4 centimeters) per year, according to the NASA statement. As a result, total solar eclipses will cease to exist in the very distant future, because the apparent size of the moon in Earth’s sky will be too small to cover the sun completely.

“Over time, the number and frequency of total solar eclipses will decrease,” Vondrak said in the statement. “About 600 million years from now, Earth will experience the beauty and drama of a total solar eclipse for the last time.”

If you want to get a headstart on trip planning, the next eclipse is going to be in Greenland, Iceland, and Spain on August 12, 2026. Cloud cover looks most favorable in Spain.

Ok, that’s all for now. Depending on what else I come across, I might update this post periodically throughout the day. I know some of you who were lucky enough to see the total eclipse shared your experiences in the comments of yesterday’s post but feel free to do so here as well.

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It’s Eclipse Day!

Hey, gang. Today is the solar eclipse, it’s supposed to be mostly sunny here in Colchester, VT, we’ve got 3 minutes and 16 seconds of totality to enjoy, and I built a solar filter for my telescope (and binoculars!), so kottke.org is going to take the day off. Edith and I will see you back here tomorrow.

In the meantime, are you doing anything for the eclipse? Anyone got any crazy camera/telescope setups? Do you think Instagram is going to crash this afternoon? Will I completely lose my mind if a cloud drifts in front of the sun today at 3:26pm ET? Is it a coincidence or a miracle that we happen to be alive during the relatively brief period of time when the moon almost exactly covers the sun, resulting in total solar eclipses? Could you imagine if the eclipse somehow doesn’t happen today??!

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Vintage Eclipse Glasses From the 1932 Eclipse

a set of eclipse glasses from 1932

From the Center for Research on Vermont at UVM, a pair of eclipse glasses from 1932. I found a product listing for these — they were marketed as the Eclipse-O-Scope and sold for 10¢.

VPR’s Nina Keck recently interviewed Floyd Van Alstyne, who is currently 104 but was 12 years old during the 1932 eclipse:

KECK: It was in the middle of the depression, he reminds me. And while he learned about the eclipse in his one-room schoolhouse, he doesn’t recall too much hoopla surrounding it.

F VAN ALSTYNE: I don’t know. We didn’t think much about general things in those days like they do now. Or we thought about minding their own business, I guess.

(thx, caroline)

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Film Footage of a Total Solar Eclipse from 1900

In 1900, celebrated magician (and astronomy enthusiast) Nevil Maskelyne travelled to North Carolina to film a solar eclipse on May 28, 1900. The Royal Astronomical Society and the British Film Institute reckon this is “the first surviving astronomical film in the world”.

In 1898 he travelled to India to photograph an eclipse. He succeeded but the film can was stolen on his return journey home.

It was not an easy feat to film. Maskelyne had to make a special telescopic adapter for his camera to capture the event. This is the only film by Maskelyne that we know to have survived.

The original film fragment held in The Royal Astronomical Society’s archive has been painstakingly scanned and restored in 4K by conservation experts at the BFI National Archive, who have reassembled and retimed the film frame by frame. The film is part of BFI Player’s recently released Victorian Film collection, viewers are now able to experience this first film of a solar eclipse since the event was originally captured over a century ago.

(via boing boing)

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A Graph of Solar Eclipse Coolness: Totality or GTFO

A partial eclipse is like a cool sunset. A total eclipse is like someone broke the sky

As usual, XKCD is spot on with this graph of solar eclipse coolness as a function of distance from the path of totality. The image’s alt text reads:

A partial eclipse is like a cool sunset. A total eclipse is like someone broke the sky.

See also the 2017 version. After witnessing the 2017 total solar eclipse, I wrote:

We saw the Baily’s beads and the diamond ring effect. And then…sorry, words are insufficient here. When the Moon finally slipped completely in front of the Sun and the sky went dark, I don’t even know how to describe it. The world stopped and time with it. During totality, Mouser took the photo at the top of the page. I’d seen photos like that before but had assumed that the beautifully wispy corona had been enhanced with filters in Photoshop. But no…that is actually what it looks like in the sky when viewing it with the naked eye (albeit smaller). Hands down, it was the most incredible natural event I’ve ever seen.

Vi Hart:

I’m not sure exactly what I expected, but this wasn’t it. I’d seen photos of coronas around suns, but this wasn’t that. And I’d expected that those photos, like many astronomical pictures, are long exposure, other wavelengths, and otherwise capturing things the naked eye can’t see. I thought there might be a glow of light in a circle, or nothing, or, I don’t know. What I did not expect was an unholy horror sucking the life and light and warmth out of the universe with long reaching arms, that what I’d seen in pictures was not an exaggeration but a failure to capture the extent of this thing that human eyes, and not cameras, are uniquely suited to absorb the horror of.

Annie Dillard:

I had seen a partial eclipse in 1970. A partial eclipse is very interesting. It bears almost no relation to a total eclipse. Seeing a partial eclipse bears the same relation to seeing a total eclipse as kissing a man does to marrying him, or as flying in an airplane does to falling out of an airplane. Although the one experience precedes the other, it in no way prepares you for it.

I am so looking forward to Monday and crossing my fingers for clear skies — the path of totality goes right over my house.

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Swirling Magnetic Fields Visible in New Black Hole Images

swirling image of the black hole at the center of the Milky Way galaxy

swirling image of the black hole at the center of the M87 galaxy

It’s been about five years since scientists captured the first blurry image of a black hole. Using what they learned from that experience, they’ve teased out some more detailed images of the black holes at the centers of the Milky Way galaxy (top) and the M87 galaxy (bottom). The process of collecting the data for these images is interesting:

The only way to “see” a black hole is to image the shadow created by light as it bends in response to the object’s powerful gravitational field. As Ars Science Editor John Timmer reported in 2019, the EHT isn’t a telescope in the traditional sense. Instead, it’s a collection of telescopes scattered around the globe. The EHT is created by interferometry, which uses light in the microwave regime of the electromagnetic spectrum captured at different locations. These recorded images are combined and processed to build an image with a resolution similar to that of a telescope the size of the most distant locations. Interferometry has been used at facilities like ALMA (the Atacama Large Millimeter/submillimeter Array) in northern Chile, where telescopes can be spread across 16 km of desert.

In theory, there’s no upper limit on the size of the array, but to determine which photons originated simultaneously at the source, you need very precise location and timing information on each of the sites. And you still have to gather sufficient photons to see anything at all. So atomic clocks were installed at many of the locations, and exact GPS measurements were built up over time. For the EHT, the large collecting area of ALMA-combined with choosing a wavelength in which supermassive black holes are very bright-ensured sufficient photons.

The images of the two black holes look similar, which was somewhat unexpected:

While this idea may initially sound somewhat mundane, it is anything but. The result is surprising because Sgr A*’s mass is about 4.3 million times that of the Sun, while M87*’s is about 6.5 billion times that of the Sun. Despite the significant difference in mass between the two supermassive black holes, the fact that their magnetic fields behave similarly and are both well-organized is an incredible discovery.

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Milky Way Embroidery

an embroidery piece of the Milky Way above a flowery meadow

an embroidery piece of the Milky Way above a flowery meadow

an embroidery piece of the Milky Way above a flowery meadow

I love Yuliya Krishchik’s space-themed embroidery pieces, especially the ones featuring Milky Way-like star fields — she calls them “surreal space landscapes”. If you watch one of Krishchik’s videos, you can see that her pieces are just a bit 3D…a cool effect.

You can find more of her work on Instagram and her blog or buy original pieces in her store (they go quickly though).

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The Vela Supernova Remnant

an image of the Vela supernova remnant

This stunning 1.3 gigapixel image of the Vela supernova remnant comes to us courtesy of the Dark Energy Camera at the Cerro Tololo Inter-American Observatory in Chile. From PetaPixel:

The Vela Supernova remnant, located about 800 light-years away from Earth, is the cosmic corpse of a massive star that exploded 11,000 years ago. It is one of the closest supernova remnants to Earth and the perfect subject for the remarkable Dark Energy Camera.

The supernova is a vast cosmic structure about 100 light-years across. For context, one would have to travel around the Earth 200 million times to have traveled a single light-year.

an image of the Vela supernova remnant that shows some of its structure

The full image of the supernova remnant is worth exploring. You can also watch this zoom-in of the image to observe the high level of detail available.

(via colossal)

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I Put 4 Million Suns in a Black Hole Over New York

Using a scale model of the solar system the size of New York City and some dazzling visual effects, Epic Spaceman explains that black holes are generally smaller than you might think (because they’re so dense) — even the supermassive black hole at the center of our galaxy. But when you consider some of the biggest black holes we’ve discovered…wow.

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All of U.S. History Has Taken Place in One Plutonian Year

Back in 2015, as the New Horizons probe was approaching Pluto, NASA posted an illustration of the dwarf planet’s orbital timeline:

an orbital timeline of Pluto's orbit around the Sun

A short piece on Vox then noted:

The entire history of the United States has unfolded in the time it’s taken Pluto to orbit the Sun once.

And that’s still true! But just barely. Pluto takes 247.94 Earth years to orbit the Sun. According to my calculations, the Plutonian year that started on July 4, 1776 will end this year on June 12, 2024 (give or take a few hours).

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Meet Venus’s Newly Named Quasi-Moon: Zoozve

a portion of a solar system map showing an object called Zoozve orbiting Venus

A couple of weeks ago, Radiolab aired an episode about a puzzling object on a children’s poster of the solar system: a Venusian moon called Zoozve. Venus doesn’t have any moons and “Zoozve” didn’t show up on Google at all, so co-host Latif Nasser went on a bit of a mission to find out what the heck this object was. He talked to someone at NASA, the poster’s designer, and various astronomers and physicists, including the person who had discovered Zoozve (aka 2002 VE68).

So begins a tiny mystery that leads to a newly discovered kind of object in our solar system, one that is simultaneously a moon, but also not a moon, and one that waltzes its way into asking one of the most profound questions about our universe: How predictable is it, really? And what does that mean for our place in it?

It’s an entertaining listen and you’ll want to catch the follow-up as well, which I won’t spoil for you. And if you’re a reader rather than a listener, this piece at space.com recaps the whole thing.

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