Seán Doran took 78,846 frames of data compiled by the Solar Dynamics Observatory over the course of a month and made this absolutely fantastic time lapse of the Sun slowly rotating and burning and flaring. Put this on the biggest, high-resolution screen you can and pretend you’re in the solar observation room of the Icarus II in Sunshine.
See also A Decade of Sun and Gorgeous Time Lapse of the Sun. (via colossal)
For the last nine months, NASA’s Perseverance rover has been rolling around on Mars taking photos and doing science. It’s also been recording audio of its environment with a pair of microphones and in this video, a pair of NASA scientists share some of those recordings and what we might learn about Mars from them.
This is one of my absolute favorite sounds. This is the sound of a helicopter flying on Mars. We used this sound to actually understand the propagation of sound in general through the Martian atmosphere, and it turns out that we were totally wrong with our models. The Martian atmosphere can propagate sound a lot further than we thought it could.
And surprisingly for me, that’s my friend Nina in the video! (We eclipse-chased together in 2017.) I knew she was working on the rovers but didn’t know she was going to pop up in this video I found on Twitter this morning. Fun!
Marcella Giulia Pace photographed the Moon in 48 different hues and arranged them in a lovely spiral pattern.
I have collected some of my Full Moon shots taken over the past 10 years. I selected the shades of color with which the Moon was filmed in front of my lens and my eyes.
The atmosphere gives different colors to our satellite (scattering) based on its height with respect to the horizon, based on the presence of humidity or suspended dust. The shape of the Moon also changes: at the bottom of the horizon, refraction compresses the lunar disk at the poles and makes it look like an ellipse.
The full moon was wonderful last night and Andrew McCarthy captured this colorful image of our nearest celestial companion. McCarthy explained where all those colors come from:
Back to this image, this was captured through a telescope and involved capturing thousands of frames to reveal the details. But what about the colors? The moon is gray, of course, but not *perfectly* gray. Some areas have a subtle blue tint, and others have a more orange tint. By teasing out those subtle colors, I can reveal the mineral composition of the moon! Blues denote titanium presence, while orange shows iron and feldspar present in the regolith. You can also see how impacts paint the surface with fresh color in the ejecta as they churn up material.
A print is available, but only for a very limited time (~6 more hours as of pub time).
The Royal Museum Greenwich has announced the winners of the Astronomy Photographer of the Year for 2021. Zhong Wu won the galaxies category with a 360-degree view of the Milky Way (above, top), a mosaic which took two years to create — the northern hemisphere portion of the galaxy was photographed in China and the southern part in New Zealand. Jeffrey Lovelace’s photo of the crescent moon over Death Valley sand dunes (above, bottom) took the prize in the skyscapes category.
I love this post from the NYPL comparing astronomical drawings by E.L. Trouvelot done in the 1870s to contemporary NASA images.
Trouvelot was a French immigrant to the US in the 1800s, and his job was to create sketches of astronomical observations at Harvard College’s observatory. Building off of this sketch work, Trouvelot decided to do large pastel drawings of “the celestial phenomena as they appear…through the great modern telescopes.”
He made drawings of Saturn, Jupiter, aurora borealis, the Milky Way, and more. Here’s his incredible drawing of sun spots compared to a recent image of the Sun’s surface:
And his drawing of a solar eclipse compared to a recent image:
Check out the post for more examples of Trouvelot’s work.
Black holes are the largest single objects in the universe, many times larger than even the biggest stars, and have no upper limit to their size. But practically, how big is the biggest, heaviest black hole in the universe? (A: More massive than the entire Milky Way.)
The largest things in the universe are black holes. In contrast to things like planets or stars they have no physical size limit, and can literally grow endlessly. Although in reality specific things need to happen to create different kinds of black holes, from really tiny ones to the largest single things in the universe. So how do black holes grow and how large is the largest of them all?
Videos about space are where Kurzgesagt really shines. I’ve seen all their videos about black holes and related objects, and I always pick up something I never knew whenever a new one comes out. This time around, it was quasistars and the surprisingly small mass of supermassive black holes located at galactic centers compared to the galaxies themselves.
The Royal Museums Greenwich has announced the shortlist for the 2021 Astronomy Photographer of the Year competition. I’ve included a few favorites above (by Andrew McCarthy, Larryn Rae, and Stefan Liebermann) but you can check out the rest on their site. (via curious about everything)
As I’ve written before, in the history of astronomy and astrophysics, women have made major discoveries and played a significant role in advancing our understanding of the universe but have often not gotten the recognition their male peers enjoy. In 1967, while she was working on her doctoral research with her advisor Antony Hewish, Jocelyn Bell Burnell (then Jocelyn Bell) discovered a new and unusual kind of object, the pulsar. In this short documentary, Bell Burnell shares her story — how she got interested in radio astronomy, the prejudice with which she was treated as the only woman in her university program, how she discovered the first pulsar and persisted (more than once) through Hewish’s assertions that the object was “interference”, and how she was passed over for the Nobel Prize for her discovery.
In 2018, Bell Burnell was awarded the Special Breakthrough Prize in Fundamental Physics “for fundamental contributions to the discovery of pulsars, and a lifetime of inspiring leadership in the scientific community”, joining past honorees like the LIGO team, Stephen Hawking, and the team that discovered the Higgs boson. She donated the entire $3 million prize to the Institute of Physics to help support “PhD physics students from under-represented groups” with their educations.
It’s not justice, but I will note that Bell Burnell’s Wikipedia page is longer and more substantial than Hewish’s, despite his Nobel.
After Neil Armstrong and Buzz Aldrin landed on the Moon 52 years ago today in the Lunar Module (aka Eagle), they rode the ascent stage of the LM back to rendezvous with Michael Collins in the Command Module (aka Columbia). After docking, Eagle was jettisoned and the three astronauts returned to Earth in Columbia. It was presumed that Eagle orbited the Moon until eventually crashing into the surface, but a recent analysis shows that the spacecraft may have entered a stable orbit and is still circling the Moon decades after the end of the mission, a priceless artifact of an historic achievement.
Most spacecraft in lunar orbit suffer from instability in their orbits due to the ‘lumpy’ nature of the lunar gravity which tends to cause the orbits to eventually get so elliptical that they hit the moon.
However, an amateur space fan wanted to narrow down the possible impact location and used orbit modelling software to propagate the orbit forwards in time until it hit the moon. He was surprised to find that it didn’t hit the moon, and remained in a stable orbit for decades, this suggests that the Eagle may still be orbiting the moon over 5 decades after being left there.
The paper detailing the analysis suggests that if Eagle has survived, it should be detectable by radar.
This is an animation of how quickly an object falls 1 km to the surfaces of solar system objects like the Earth, Sun, Ceres, Jupiter, the Moon, and Pluto. For instance, it takes 14.3 seconds to cover that distance on Earth and 13.8 seconds on Saturn.
It might be surprising to see large planets have a pull comparable to smaller ones at the surface, for example Uranus pulls the ball down slower than at Earth! Why? Because the low average density of Uranus puts the surface far away from the majority of the mass. Similarly, Mars is nearly twice the mass of Mercury, but you can see the surface gravity is actually the same… this indicates that Mercury is much denser than Mars.
(via @thekidshouldsee)
The US Postal Service has released a set of Sun Science stamps that use images from NASA’s Solar Dynamics Observatory to illustrate different solar phenomena like plasma blasts, sunspots, and solar flares.
Printed with a foil treatment that adds a glimmer to the stamps, the images on these stamps come from NASA’s Solar Dynamics Observatory, a spacecraft launched in February 2010 to keep a constant watch on the sun from geosynchronous orbit above Earth. The striking colors in these images do not represent the actual colors of the sun as perceived by human eyesight. Instead, each image is colorized by NASA according to different wavelengths that reveal or highlight specific features of the sun’s activity.
One of the stamps highlights sunspots, two feature images of coronal holes, two show coronal loops, two depict plasma blasts, one is a view of an active sun that emphasizes its magnetic fields, and two show different views of a solar flare.
NASA has more on the science behind the images on the stamps and the whole set of stamps are available for purchase online.
See also A Decade of the Sun.
Well, this is cool: a recently discovered minor planet estimated to be between 62 and 230 miles across is currently journeying through our solar system and sometime in 2031 will be almost as close to the Sun as Saturn.
And it turns out, astronomers are about to witness the closest pass of this incredible round trip. Currently, 2014 UN271 is about 22 Astronomical Units (AU) from the Sun (for reference, Earth is 1 AU from the Sun). That means it’s already closer than Neptune, at 29.7 AU. And it’s not stopping there — it’s already traveled 7 AU in the last seven years, and at its closest in 2031, it’s expected to pass within 10.9 AU of the Sun, almost reaching the orbit of Saturn.
Before then, it’s expected to develop the characteristic coma and tail of a comet, as icy material on its surface vaporizes from the heat of the Sun. This close pass would give astronomers an unprecedented close look at Oort cloud objects.
C’mon NASA, let’s a get a probe fired up and visit this very unusual object!
To inspire folks to seek out their own galactic vistas, Capture the Atlas has chosen the best photos of the Milky Way for 2021. The top photo was taken by Daniel Thomas Gum in Australia and the bottom one by Larryn Rae in New Zealand. Check out the rest of the selections here.
In the history of science, there are women who have made significant contributions to their field but haven’t gotten the recognition that their male peers have. The field of astronomy & astrophysics in particular has had many female pioneers — Vera Rubin, Cecilia Payne-Gaposchkin, Annie Jump Cannon, Nancy Grace Roman, Maria Mitchell, Jocelyn Bell Burnell, Henrietta Swan Leavitt, Caroline Herschel, Williamina Fleming, and many others. Add to that list Hisako Koyama, a Japanese astronomer whose detailed sketches of the Sun over a 40-year period laid the foundation for a 400-year timeline of sunspot activity, which has aided researchers in studying solar cycles and magnetic fields.
Ms. Koyama was a most unusual woman of her time. As a scientist, she bridged the amateur and professional world. She preferred “doing” activities: observing, data recording, interacting with the public, and writing. No doubt many Japanese citizens benefited from personal interaction with her. The space and geophysics community continues to benefit from her regular and precise observations of the Sun. Although we know very little of her young personal life other than she was relatively well educated and had a father who supported her desire to view the skies by providing a telescope, we can see from snippets in Japanese amateur astronomy articles that she had a passion for observing, as revealed in her 1981 article: “I simply can’t stop observing when thinking that one can never know when the nature will show us something unusual.”
Here are a few of her sunspot sketches, the top two done using her home telescope and the bottom one using the much larger telescope at the National Museum of Nature and Science (that shows the largest sunspot of the 20th century):
(via the kid should see this)
This is a photo of a tiny tiny snippet of the universe, taken by the Hubble Space Telescope. Every object you see in the photo is a staggeringly massive galaxy that contains hundreds of billions of stars along with all sort of other things.
Our own galaxy, the Milky Way, is well over one hundred thousand light years across. We only see a pitiful portion of it. Although it contains several hundred billion stars in its expanse, we can only see a fraction of a fraction of them.
And even that doesn’t fully capture the essence of a galaxy, which also has planets, gas, dust, dark matter, and more. Galaxies are colossal objects, their true nature only becoming apparent to us a century ago.
I know I’ve posted photos like this before, but every time I see something like this, my mind boggles anew at the sheer scale and magnitude of it all and I just have to share it.
P.S. And Earth contains the only sentient life in the entire universe? Lol.
Jon Larsen collects and photographs micrometeorites from all over the world, finding them even in urban areas mixed in among terrestrial dust and dirt.
The cosmos is a swirling soup of stardust. Every day, approximately 60 tons of dust from asteroids, comets, and other celestial bodies fall to the Earth. These tiny metallic, alien stones of various shapes, textures, and colors-known as micrometeorites-are some of the oldest pieces of matter in the solar system.
Even though micrometeorites blanket the Earth, scientists have generally only been able to discover them in remote places devoid of human presence, such as Antarctic ice, desolate deserts, and deep-sea sediments. Scientists began searching for micrometeorites in the 1960s, and they predominantly thought the extraterrestrial dust would be impossible to find in urban environments. The conventional wisdom held that densely populated areas had too much man-made sediment that camouflaged the tiny space particles.
But Jon Larsen, a Norwegian jazz musician and creator of Project Stardust, was able to show that it is possible to find micrometeorites in more populated areas. In a study published in January 2017 in the journal Geology, he and his colleagues catalogued more than 500 lustrous micrometeorites (and counting), all recovered from rooftops in urban areas.
Check out Larsen’s Project Stardust for more photos and information on how to hunt for your own. (via the kid should see this)
This video focuses on one of my favorite astrophysics facts: 94% of the observable universe is permanently unreachable by humans. (Unless we discover faster-than-light travel, but that’s fantasy at this point.)
This expansion means that there is a cosmological horizon around us. Everything beyond it, is traveling faster, relative to us, than the speed of light. So everything that passes the horizon, is irretrievably out of reach forever and we will never be able to interact with it again. In a sense it’s like a black hole’s event horizon, but all around us. 94% of the galaxies we can see today have already passed it and are lost to us forever.
“Since you started watching this video, around 22 million stars have moved out of our reach forever.” And future generations, billions of years from now, won’t even be able to see any other galaxies or detect cosmic background radiation, making knowledge about the Big Bang impossible.
Astrophotography enthusiast Andrew McCarthy took a 140-megapixel photo of the Sun yesterday and, gosh, the Sun is just so cool to look at. I don’t know if you can see it above, but there’s a little something hidden in the photo, a transiting ISS:
The full-size image is available to McCarthy’s supporters on Patreon.
For his Earth Restored project, Toby Ord digitally remastered 50 photographs of the whole Earth taken by Apollo astronauts during their missions in the 60s and 70s.
The Apollo photographs are historic works of art. So in restoring them, I sought to bring out their own beauty. I refrained from recomposing the images by cropping, or trying to leave my own mark or interpretation. Perhaps in some cases this would make a more pleasing image, but it was not my aim.
And the Apollo photographs are also a scientific record of what our Earth looks like. In particular, what it would have looked like from the perspective of the astronaut taking the shot. So rather than pumping the saturation or adjusting the colours to what we think the Earth looks like, I wanted to allow us to learn from these photographs something about how it actually appears.
Many of these shots are new to me — the Apollo program and its scientific and cultural output continue to be revelatory 50 years later.
Update: Full resolution images are available when you click through on each photo. You may have to make your browser window wider to see the link. (thx, colin)
Deployed from NASA’s Perseverance rover, the Ingenuity helicopter took off and hovered for about 30 seconds in its first flight early this morning.
The solar-powered helicopter first became airborne at 3:34 a.m. EDT (12:34 a.m. PDT) — 12:33 Local Mean Solar Time (Mars time) — a time the Ingenuity team determined would have optimal energy and flight conditions. Altimeter data indicate Ingenuity climbed to its prescribed maximum altitude of 10 feet (3 meters) and maintained a stable hover for 30 seconds. It then descended, touching back down on the surface of Mars after logging a total of 39.1 seconds of flight. Additional details on the test are expected in upcoming downlinks.
Ingenuity’s initial flight demonstration was autonomous — piloted by onboard guidance, navigation, and control systems running algorithms developed by the team at JPL. Because data must be sent to and returned from the Red Planet over hundreds of millions of miles using orbiting satellites and NASA’s Deep Space Network, Ingenuity cannot be flown with a joystick, and its flight was not observable from Earth in real time.
NASA livestreamed the team in Mission Control as the test results were transmitted back to Earth. The photo above is of Ingenuity’s shadow taken while in flight by its onboard camera.
Update: Here’s video footage of the first flight:
And there’s always room for a little Great Span on this site. Alex Knapp:
The world’s oldest living person was alive when the Wright Brothers flew at Kitty Hawk and when the first helicopter flew on Mars.
Last month I shared a video of the Earth rising over the surface of the Moon captured by Japan’s Kaguya orbiter. It’s a good clip but quite short and over-narrated. Seán Doran took several Earthrise & Earthset sequences filmed by Kaguya, remastered & upsampled them to 4K resolution, and stitched them together into this wonderful video, set to music by Jesse Gallagher. One of the sequences, which begins around the 5-minute mark, captures a solar eclipse of the Sun by the rising Earth. I hadn’t seen this footage before and had to pick my jaw up off the floor — absolutely spectacular.
What if a giant banana was orbiting the Earth at the same distance as the ISS? What would that look like? Well, it would look something like this.
See also If the Planets Were As Close As the Moon.
Captured by the Kaguya lunar orbiter on April 5, 2008, this is an HD video of the Earth rising over the surface of the Moon. Watching stuff like this always puts me in a different frame of mind. (Turn off the sound if you don’t want to hear the super-cheesy narration.)
NASA engineers encoded a secret message in the parachute the Perseverance rover used to slow its descent to the surface of Mars. Tanya Fish provided a handy guide to decoding it on Twitter and as a PDF available on GitHub.
Just a few days after the Perseverance rover successfully touched down on Mars, NASA has released onboard video from the descent and landing from multiple perspectives. I watched this with my kids last night and all three of us had our mouths hanging open.
The real footage in this video was captured by several cameras that are part of the rover’s entry, descent, and landing suite. The views include a camera looking down from the spacecraft’s descent stage (a kind of rocket-powered jet pack that helps fly the rover to its landing site), a camera on the rover looking up at the descent stage, a camera on the top of the aeroshell (a capsule protecting the rover) looking up at that parachute, and a camera on the bottom of the rover looking down at the Martian surface.
After watching it again just now, I am struck by two things:
Can’t wait to see more from Perseverance once the science program gets cranking.
Today is the day! NASA’s latest Mars rover is scheduled to touch down on the surface of Mars at around 3:55pm EST today1 and you can follow along online. You probably know the drill by now: what you’ll be watching isn’t actually live (it’s delayed by 11 minutes & 22 seconds, the time it takes for data to reach the Earth from Mars) and there’s no video to watch…there’s just telemetry from the rover that indicates where it is and what it’s doing. But I can say having watched the Curiosity landing in 2012, it’s still super exciting and nerve-wracking.
NASA has a number of ways to watch online, including their main stream on YouTube (embedded above), en Español, the “clean feed” from mission control without commentary, and a 360-degree stream, as well as options on Twitter, Facebook, Twitch, etc. You can also watch on NASA TV or through NASA apps on your phone, tablet, or TV. The coverage starts at 2:15pm EST (find your local time) and if all goes well, things start to get exciting at about 3:38pm EST and the landing will happen around 3:55pm EST. To get ready, you can check this page for a schedule of what happens when, watch a video about what’s gonna happen, and look at this live simulated view of where the Perseverance spacecraft is now (here too). Good luck, little rover!
All times in this post (and stated by NASA in their schedules) are when we here on Earth will learn of events after the 11 minute & 22 second informational travel time from Mars is factored in. So while the Mars landing will actually occur around 3:44pm EST, we won’t know about it until 3:55pm EST.↩
Curiosity is about to get some company. NASA’s newest rover, Perseverance, is set to land on Mars beginning tomorrow at around 3pm EST. The video above walks us through the 7-minute landing routine in which the rover ditches its spacecraft, heat shields its way through the Martian atmosphere, deploys its parachute, uses an onboard guidance system to navigate to a good landing spot, and finally is lowered down to the surface via a sky crane. The rover’s destination is Jezero Crater, site of an ancient river delta and lakebed.
Jezero Crater tells a story of the on-again, off-again nature of the wet past of Mars. More than 3.5 billion years ago, river channels spilled over the crater wall and created a lake. Scientists see evidence that water carried clay minerals from the surrounding area into the crater lake. Conceivably, microbial life could have lived in Jezero during one or more of these wet times. If so, signs of their remains might be found in lakebed or shoreline sediments. Scientists will study how the region formed and evolved, seek signs of past life, and collect samples of Mars rock and soil that might preserve these signs.
Here’s how you can watch the landing “live” tomorrow (i.e. delayed by the 11 minutes & 22 seconds it takes for signals to travel from Mars). I’ll do a separate post tomorrow w/ the proper YouTube embeds so we can all follow along together.
After 1405 nights of observation over 6 years, astronomers at three observatories have produced an image of the night sky that contains 10 trillion pixels of data and depicts over a billion galaxies. Bad Astronomy’s Phil Plait has the details.
It’s the result of the DESI Legacy Imagining Surveys, maps of the sky made by the three observatories (the Dark Energy Camera Legacy Survey, the Beijing-Arizona Sky Survey, and the Mayall z-band Legacy Survey, in combination with the orbiting WISE infrared observatory). They mapped the northern sky in seven colors, covering a third of the entire sky — 14,000 square degrees, or the equivalent area of 70,000 full Moons on the sky.
The ultimate goal is to better understand dark energy, the mysterious substance that’s accelerating the expansion of the Universe, by looking at the distribution of galaxies throughout the Universe. They’ll do that by picking tens of millions of the billion galaxies in the data and getting follow-up observations with the Dark Energy Spectroscopic Instrument (DESI), which will take spectra of those galaxies and find their distances.
Since we’ll know their positions on the sky, and their distances, this will make a 3D map of the Universe larger than any ever before.
The photo included at the top of the post is just a tiny tiny bit of the full image — you can pan and zoom the whole thing in this viewer. Be sure to zoom out in increments from the default view so as to fully appreciate just how absurdly large this image (and the universe) is.
The aurora borealis was amazing last night in Norway. The top photo is from Markus Varik and the bottom two are from Marianne Bergli, who runs a company that offers tours of the aurora. (via @AvatarDomy)