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.
kottke.org posts about space
The Secret Message Encoded in the Parachute of the Mars Perseverance Rover
Onboard Camera Views from Perseverance Rover’s Descent & Touchdown on Mars
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:
- Sometime in my lifetime, live broadcasts from Mars will likely become commonplace. There will be dozens or hundreds of Mars webcams you can pull up on whatever the 2052 internet equivalent is. It will be amazing how boring it all is. (Or perhaps it’ll be boring how amazing it all is.)
- That humans landed on the Moon in 1969 was an incredible feat, but a close second is that the first steps were broadcast live from the Moon’s surface to everywhere on the Earth. Unbelievable.
Can’t wait to see more from Perseverance once the science program gets cranking.
Watch NASA’s Perseverance Rover Land on Mars Live
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.↩
The Perseverance Rover Lands on Mars Tomorrow
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.
This New 10 Terapixel Image of the Night Sky Contains 1 Billion Galaxies
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.
Last Night’s Northern Lights
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)
Orbit the Moon in Realtime
Using images from the Kaguya orbiter, Seán Doran has constructed a 4-hour realtime orbit of the Moon. Feel free to pair with your favorite piece of relaxing music for a meditative viewing experience.
See also another video by Doran: An Incredible Video of What It’s Like to Orbit the Earth for 90 Minutes.
Wooden Satellites
Researchers at Kyoto University and a Japanese forestry company have joined forces to develop orbital satellites made out of wood, purportedly to address the growing threat of space junk. The design will need to be resistant to dramatic changes in temperature and sunlight but will easy burn up in the Earth’s atmosphere upon reentry.
I love the idea of satellites made from wood — it seems like Victorian-era scifi. The harshness of space seems like a domain exclusively for metals and ceramics, but wood is a surprisingly versatile material used in many different severe environments on Earth. There’s no reason it couldn’t work in space as well — and if their traditional expertise in joinery is any indication, I trust the Japanese to figure out a way make it happen.
But as Ars Technica’s John Timmer notes, wooden satellites won’t meaningfully help with the space junk problem.
Unfortunately, making satellite housings out of wood won’t help with this, for many, many reasons. To start with, a lot of the junk isn’t ex-satellites; it’s often the boosters and other hardware that got them to orbit in the first place. Housings are also only a fraction of the material in a satellite, leaving lots of additional junk untouched by the change, and any wood that’s robust enough to function as an effective satellite housing will be extremely dangerous if it impacts anything at orbital speeds.
The (unrelated) photo above is of toy company Papafoxtrot’s wooden scale models of NASA spacecraft.
Here’s What 10 Million Stars Look Like
Using the Dark Energy Camera at the Cerro Tololo observatory in Chile, astronomers took an image of the stars clustered around the center of our Milky Way galaxy that shows about 10 million stars. Check out the zoomable version for the full experience.
Looking at an image like this is always a bit of a brain-bender because a) 10 million is a huge number and b) the stars are so tightly packed into that image and yet c) that image shows just one tiny bit of our galactic center, d) our entire galaxy contains so many more stars than this (100-400 billion), and e) the Universe perhaps contains as many as 2 trillion galaxies. And if I’m remembering my college math correctly, 400 billion × 2 trillion = a metric crapload of stars. (via bad astronomy)
A 2.5 Gigapixel Image of the Orion Constellation
Amateur astronomer Matt Harbison has been working for the past five years on capturing a detailed image of the Orion constellation. He recently completed the project and the result is this 2.5 gigapixel photo mosaic composed of 12,816 individual photos. From PetaPixel, which has a good writeup of the project, a taste of the challenges involved with constructing this image:
Even after all the images were shot and each panel completed, the finished image did not come together smoothly. “I began in 2015 on a Mac Pro with 2 Xeon Processors and 64GB of RAM. This machine was easily one of the fastest computers of the day, and it carried me all the way up to panel 47 where I believe I hit the RAM limit of the computer.”
It would take five years from that point for technology to catch up to Harbison’s needs as he wouldn’t have a computer powerful enough to complete the task until August of 2020. “The new computer is an AMD Threadripper with 24 cores and 256GB of memory,” Harbison said. “It took a total of 23 hours to provide an astrometric solution for all 200 panels and then an additional 19 hours to merge into the gradient merge mosaic tool.”
What an amazing thing to be able to make from your backyard.
Watch a NASA Spacecraft Touch Down On an Asteroid to Collect a Sample
On Tuesday, NASA’s OSIRIS-REx spacecraft touched down on an asteroid called Bennu for about six seconds in order to collect a mineral sample to bring back to Earth.
The Origins Spectral Interpretation Resource Identification Security - Regolith Explorer spacecraft will travel to a near-Earth asteroid, called Bennu (formerly 1999 RQ36), and bring at least a 2.1-ounce sample back to Earth for study. The mission will help scientists investigate how planets formed and how life began, as well as improve our understanding of asteroids that could impact Earth.
The video above is a time lapse sequence of the touch down, sampling, and subsequent take off.
These images were captured over approximately a five-minute period. The imaging sequence begins at about 82 feet (25 meters) above the surface, and runs through the back-away maneuver, with the last image in the sequence taken at approximately 43 feet (13 meters) in altitude — about 35 seconds after backing away. The sequence was created using 82 SamCam images, with 1.25 seconds between frames.
Winners of the 2020 Astronomy Photographer of the Year Contest
The winning entries from the Insight Investment Astronomy Photographer of the Year 2020 competition are here and they are spectacular. As longtime readers can attest, I will never get tired of looking at photos of the sky and space.
Above from top to bottom: Nicolas Lefaudeux’s tilt-shift shot of the Andromeda Galaxy, Alain Paillou’s ultra-contrasty photo of the Moon, Kristina Makeeva’s aurora shot, Evan McKay’s self-portrait under the Milky Way, and Olga Suchanova’s 3-month exposure of the Sun’s path through the sky using a beer can pinhole camera. You can read a little bit about how Suchanova got that shot on 35mmc:
If exposure times on the order of minutes seem long, try months. Olga Suchanova (London, UK) used a pinhole camera made from a beercan — and not just any beercan, but a Peter Saville design for the Tate Modern — to record the solargraph below.
She used Ilford paper, exposed for 3 or 4 months at an art residency in Almeria, Spain. The long exposure traces the sun’s path across the sky over multiple days — sunny days make brighter lines, and as spring turns to summer, the sun rises higher in the sky. The fantastic colours — another consequence of the long exposure — are created spontaneously on black and white paper, without the need for development or any other chemical processing.
Challenger: The Final Flight
From Netflix, Challenger: The Final Flight is a four-part documentary series about the 1986 Challenger Space Shuttle disaster.
Incorporating never-before-seen interviews and rare archival material, this series offers an in-depth look at one of the most diverse crews NASA assembled, including high school teacher Christa McAuliffe, who was selected to be the first private citizen in space.
The series debuts on Netflix on Sept 16.
Interior Space: A Visual Exploration of the International Space Station
Roland Miller, a long-time photographer of space exploration projects, and Italian astronaut Paolo Nespoli has teamed up to produce a book of photographs of the interior of the International Space Station. According to a profile of the project from Colossal, Miller used interior views of the ISS on Google Earth to stage shots, which would then be executed by Nespoli in space. Nespoli, an engineer, also built a stabilizing rig for the camera.
Because the ISS was in a weightless environment with fluctuating light, many of the images astronauts typically capture utilize a flash, which Miller, who generally photographs using a very low shutter speed, wanted to avoid. “The first problem you run into is you can’t use a tripod in space because it just floats away, and the station itself is going 17,500 miles an hour. Just because of the size and the speed, there’s a harmonic vibration to it,” he notes. To combat the constant quivering, Nespoli constructed a stabilizing bipod and shot about 135 images with a high shutter speed, before sending the shots to Miller for aesthetic editing.
You can get a copy of the book (or prints) by backing the project on Kickstarter.
New Solar Telescope Finds “Campfires” on the Sun
The European Space Agency’s Solar Orbiter is not even at its closest distance to the Sun and its telescope has already captured some images that reveal new information about our star, including features called “campfires” that are too small to have been captured by previous instruments. From the description of the video embedded above:
This animation shows a series of close-up views captured by the Extreme Ultraviolet Imager (EUI) at wavelengths of 17 nanometers, showing the upper atmosphere of the Sun, or corona, with a temperature of around 1 million degrees.
These images reveal a multitude of small flaring loops, erupting bright spots and dark, moving fibrils. A ubiquitous feature of the solar surface, uncovered for the first time by these images, have been called ‘campfires’. They are omnipresent miniature eruptions that could be contributing to the high temperatures of the solar corona and the origin of the solar wind.
The Solar Orbiter can also peek around the back side of the Sun for the first time:
“Right now, we are in the part of the 11-year solar cycle when the Sun is very quiet,” says Sami Solanki, the director of the Max Planck Institute for Solar System Research in Gottingen, Germany, and PHI Principal Investigator. “But because Solar Orbiter is at a different angle to the Sun than Earth, we could actually see one active region that wasn’t observable from Earth. That is a first. We have never been able to measure the magnetic field at the back of the Sun.”
As revealing as these first images are, at its closest approach later in the mission the Solar Orbiter’s resolving power will roughly double. Can’t wait to see what else it turns up.
Gorgeous 4K Video of Mars
To create this ultra HD footage of the surface of Mars, high-definition panoramas created from hundreds of still photos taken by the Mars rovers are panned over using the Ken Burns effect. The end product is pretty compelling — it’s not video, but it’s not not video either.
A question often asked is: ‘Why don’t we actually have live video from Mars?’
Although the cameras are high quality, the rate at which the rovers can send data back to earth is the biggest challenge. Curiosity can only send data directly back to earth at 32 kilo-bits per second.
Instead, when the rover can connect to the Mars Reconnaissance Orbiter, we get more favourable speeds of 2 Megabytes per second.
However, this link is only available for about 8 minutes each Sol, or Martian day.
As you would expect, sending HD video at these speeds would take a long long time. As nothing really moves on Mars, it makes more sense to take and send back images.
(thx, paul)
Live TV Coverage of the Apollo 11 Landing and Moon Walk
Fifty-one years ago today, on July 20, 1969, Neil Armstrong & Buzz Aldrin landed on the Moon and went for a little walk. For the 12th year in a row, you can watch the original CBS News coverage of Walter Cronkite reporting on the Moon landing and the first Moon walk on a small B&W television, synced to the present-day time. Just open this page in your browser today, July 20th, and the coverage will start playing at the proper time. Here’s the schedule (all times EDT):
4:10:30 pm: Moon landing broadcast starts
4:17:40 pm: Lunar module lands on the Moon
4:20:15 pm - 10:51:26 pm: Break in coverage
10:51:27 pm: Moon walk broadcast starts
10:56:15 pm: First step on Moon
11:51:30 pm: Nixon speaks to the Eagle crew
12:00:30 am: Broadcast end (on July 21)
Set an alarm on your phone or calendar!
This is one of my favorite things I’ve ever done online…here’s what I wrote when I launched the project in 2009:
If you’ve never seen this coverage, I urge you to watch at least the landing segment (~10 min.) and the first 10-20 minutes of the Moon walk. I hope that with the old time TV display and poor YouTube quality, you get a small sense of how someone 40 years ago might have experienced it. I’ve watched the whole thing a couple of times while putting this together and I’m struck by two things: 1) how it’s almost more amazing that hundreds of millions of people watched the first Moon walk *live* on TV than it is that they got to the Moon in the first place, and 2) that pretty much the sole purpose of the Apollo 11 Moon walk was to photograph it and broadcast it live back to Earth.
In 2018, I wrote about what to watch for during the landing sequence.
The radio voices you hear are mostly Mission Control in Houston (specifically Apollo astronaut Charlie Duke, who acted as the spacecraft communicator for this mission) and Buzz Aldrin, whose job during the landing was to keep an eye on the LM’s altitude and speed - you can hear him calling it out, “3 1/2 down, 220 feet, 13 forward.” Armstrong doesn’t say a whole lot…he’s busy flying and furiously searching for a suitable landing site. But it’s Armstrong that says after they land, “Houston, Tranquility Base here. The Eagle has landed.”. Note the change in call sign from “Eagle” to “Tranquility Base”. :)
The Best Photos of Comet Neowise
Sometimes I forget what a big space dork I am and then a comet comes along and I’m texting everyone I know to get their asses outside to see the amazing sky thing. Anyway, what I’m trying to say is that this is a Comet Neowise fan blog now. After seeing it last night in my backyard,1 I went looking for some of the best photos of it.
My favorite so far is from Thierry Legault (website) of the comet over Mont-Saint-Michel in France.
In Focus’s Alan Taylor shared a selection of photographs from around the world, including this one from Mika Laureque.
Colossal featured this shot by Lester Tsai of Neowise directly over Mt. Hood. Dang.
More Comet Neowise photography can be see at USA Today, NASA, Sky & Telescope, and Astronomy Picture of the Day (1, 2, 3, 4, 5).
After seeing it briefly two nights ago before some haze settled in (and only then with the aid of binoculars), I stepped out on my deck last night just after 10pm and bam, it was right there, totally visible with the naked eye. I grabbed the binoculars and got a pretty good view and then got out the telescope. Whoa, papa. Totally mind-blowing.↩
How to Find Comet NEOWISE in the Night Sky This Month
If you live in the US and Canada, you might have the opportunity to check out Comet NEOWISE over the next few weeks with a good pair of binoculars or even with the naked eye. EarthSky has the skinny.
By mid-July (around July 12-15), the comet will also become visible at dusk (just after sunset), low in the northwest horizon, for observers in the mid- and northern U.S. How can it be visible in both dawn and dusk? The answer is that the comet is now very far to the north on the sky’s dome. For those at latitudes like those in the southern U.S. (say, around 30 degrees north latitude), the comet is very nearly but not quite circumpolar, that is, it’s nearly in the sky continually, but it isn’t quite … that’s why we at southerly latitudes will have a harder time spotting it in the evening.
It appears this comet is holding up better than Comet ATLAS did earlier in the year. Here’s a beautiful time lapse of NEOWISE rising over the Adriatic Sea in the early dawn:
And a time lapse of the comet from the International Space Station (it starts rising around the 3-minute mark):
Apart Together
October 31, 2000 was the last day all humans were together on Earth. That day, the rocket containing the crew of Expedition 1 lifted off from the Baikonur Cosmodrome in Kazakhstan and carried them to the International Space Station for a long-term stay. Fittingly, the mission left from the same launchpad that was used to launch Yuri Gagarin into space on April 2, 1961, which was the first time in history that all humans were not together on Earth. Ever since the Expedition 1 crew docked, there’s been an uninterrupted human presence on the ISS, which may continue until 2028 or 2030, by which time there may be humans on the Moon or Mars on a permanent basis. Will humans ever be only Earth-bound again?
BTW, I guess you could argue that the ISS isn’t really separate enough from Earth or that since regular commercial airplane flights began, humans have been separate from the Earth. You could also say that at any given time, thousands of people are in the air while jumping and therefore not on the Earth with the rest of us. I don’t find any of those arguments meaningful. Perhaps someday if space travel is more routine — “just popped up into orbit to visit my daughter” — and the human population is much more distributed, these same distinctions won’t hold, but for now the ISS is definitely apart from the Earth in a way that flying or jumping are not.
A Decade of Sun
For the past 10 years now, NASA’s Solar Dynamics Observatory (SDO) has been capturing an image of the Sun every 0.75 seconds. To celebrate, NASA created this 61-minute time lapse video of all ten years, with each second representing one day in the Sun’s life. They have helpfully highlighted some noteworthy events in the video, including solar flares and planetary transits.
12:24, June 5, 2012 — The transit of Venus across the face of the Sun. Won’t happen again until 2117.
13:50, Aug. 31, 2012 — The most iconic eruption of this solar cycle bursts from the lower left of the Sun.
43:20, July 5, 2017 — A large sunspot group spends two weeks crossing the face of the Sun.
See also Gorgeous Time Lapse of the Sun.
Teacher Tells Off Neil Armstrong for Faking the Moon Landing
In a letter recently published in a new book, A Reluctant Icon: Letters to Neil Armstrong, a teacher wrote a letter to the first human to set foot on the Moon accusing him of making the whole thing up.
To which Armstrong replied:
(via the excellent Letters of Note)
NASA & SpaceX Scheduled to Launch Astronauts Into Orbit From US Soil for First Time in 9 Years
NASA and SpaceX are scheduled to launch two astronauts into orbit this afternoon from the United States for the first time in nine years. The launch is scheduled to take place at 4:33 p.m. EDT. We’ll be watching for sure!
SpaceX is targeting Wednesday, May 27 for Falcon 9’s launch of Crew Dragon’s second demonstration (Demo-2) mission from Launch Complex 39A (LC-39A) at NASA’s Kennedy Space Center in Florida. This test flight with NASA astronauts Bob Behnken and Doug Hurley on board the Dragon spacecraft will return human spaceflight to the United States.
The mission is also the first time a private company will carry humans into orbit. You can watch the launch in the stream above with commentary (the coverage has already started — the astronauts just suited up and are on their way to launchpad 39A and now Kelly Clarkson is singing the National Anthem from her house) or with just the audio feed from Mission Control. And you can read more about the mission here.
Update: The launch got scrubbed for today — poor weather conditions. The next launch window is Saturday, May 30 at 3:22pm ET.
Full-Day Rotation of the Earth Around a Stationary Sky
Last year I posted a pair of videos showing a sky-stabilized rotation of the Earth around the starry sky. Because the Earth is our vantage point, we’re not used to seeing this view and it’s pretty trippy.
Now Bartosz Wojczyński has created a video showing full-day rotation of the Earth with footage shot in Namibia. The rotation is sped up to take only 24 seconds and is repeated 60 times to simulate about 2 months of rotation. I find this very relaxing to watch, like I’m riding in a very slow clothes dryer.
See also The Entire Plane of the Milky Way Captured in a Single Photo.
Lunar Landing Recreated from Archival NASA Photos
Using thousands of original photographs taken by astronauts during the Apollo missions, motion designer Christian Stangl and composer Wolfgang Stangl worked for 18 months to create this animated short film depicting a flight to the Moon, culminating in a landing and the exploration of the surface. (via moss & fog)
Colorful New Geological Map of the Moon
In collaboration with NASA and the Lunar and Planetary Institute, the USGS has released the first complete geological map of the Moon’s surface.
This new work represents a seamless, globally consistent, 1:5,000,000-scale geologic map derived from the six digitally renovated geologic maps (see Source Online Linkage below). The goal of this project was to create a digital resource for science research and analysis, future geologic mapping efforts, be it local-, regional-, or global-scale products, and as a resource for the educators and the public interested in lunar geology.
Strange Maps has more information on how the map came to be and what it shows.
The map was created by the U.S. Geological Service’s Astrogeology Science Center in Flagstaff, Arizona. In collaboration with NASA and the Lunar and Planetary Institute, it combined six ‘regional’ maps of the Moon made during the Apollo era (1961-1975) with input from more recent unmanned lunar missions.
This included data on the polar regions from NASA’s Lunar Orbiter Laser Altimeter (LOLA) and close-ups of the equatorial zone from the Japanese Space Agency’s recent SELENE mission.
The two images above show the entire map and a detailed view of a single area (which includes the landing sites of 3 Apollo missions) while the video shows a rotating globe version of the map.
Hubble Telescope Watches the Rare Disintegration of a Comet
Last month, I told you about Comet ATLAS, which at that time looked capable of putting on a real show in the night sky.
Except, since its discovery, the comet has been brightening at an almost unprecedented speed. As of March 17, ATLAS was already magnitude +8.5, over 600 times brighter than forecast. As a result, great expectations are buzzing for this icy lump of cosmic detritus, with hopes it could become a stupendously bright object by the end of May.
It turns out the increase in brightness was fleeting — and possibly due to the comet breaking apart. In the past week, the Hubble Space Telescope has gotten two good looks at the disintegrating comet, identifying that the main mass has broken into about 30 fragments.
“This is really exciting — both because such events are super cool to watch and because they do not happen very often. Most comets that fragment are too dim to see. Events at such scale only happen once or twice a decade,” said the leader of a second Hubble observing team, Quanzhi Ye, of the University of Maryland, College Park.
The results are evidence that comet fragmentation is actually fairly common, say researchers. It might even be the dominant mechanism by which the solid, icy nuclei of comets die. Because this happens quickly and unpredictably, astronomers remain largely uncertain about the cause of fragmentation. Hubble’s crisp images may yield new clues to the breakup. Hubble distinguishes pieces as small as the size of a house. Before the breakup, the entire nucleus may have been no more than the length of two football fields.
Apollo 11’s Post-Lunar Quarantine
I do not know if hearing about other people’s quarantine experiences makes going through one yourself any easier, but the story of how NASA sequestered the returning Apollo 11 astronauts away from the rest of the world for 21 days is interesting for other reasons as well. The worry was that some sort of “moon bug” or “lunar plague” was going to make its way from the Moon to the Earth in the spacecraft or the astronauts’ bodies.
From the moment the Apollo 11 astronauts arrive back on earth from their epochal visit to the moon, they will be treated not as heroes but as bearers of the most virulent, devastating plague the world has ever known.
So NASA quarantined Armstrong, Aldrin, and Collins in a series of specially designed suits and environments until August 10, 1969. At one point, the three of them lived in a modified Airstream trailer in which the air pressure was lower on the inside than outside so if there was a leak, air would rush into the trailer, not out. Armstrong even celebrated a birthday in quarantine.
After Apollo 11, NASA did similar quarantines for 12 and 14 but abandoned them after that because they figured it was safe.
Oh, and if you were curious about the Soyuz launch yesterday that sent three astronauts to the ISS and how they were going to mitigate the chances of sending any SARS-CoV-2 up there, crews on all missions are subject to a mandatory 2 week quarantine before they leave (according to this press release).
Recently Discovered Comet Might Put On a Show
Back in late December, a new comet called Comet ATLAS (or C/2019 Y4) was discovered by a robotic astronomical survey on the lookout for objects that may strike the Earth. Don’t worry, Comet ATLAS isn’t going to hit us, but it has a chance to put on quite a show.1 It didn’t seem like much at first, but since its discovery Comet ATLAS has gotten brighter much faster than scientists have expected.
When astronomers first spotted Comet ATLAS in December, it was in Ursa Major and was an exceedingly faint object, close to 20th magnitude. That’s about 398,000 times dimmer than stars that are on the threshold of naked-eye visibility. At the time, it was 273 million miles (439 million kilometers) from the sun.
But comets typically brighten as they approach the sun, and at its closest, on May 31, Comet ATLAS will be just 23.5 million miles (37.8 million km) from the sun. Such a prodigious change in solar distance would typically cause a comet to increase in luminosity by almost 11 magnitudes, enough to make ATLAS easily visible in a small telescope or a pair of good binoculars, although quite frankly nothing really to write home about.
Except, since its discovery, the comet has been brightening at an almost unprecedented speed. As of March 17, ATLAS was already magnitude +8.5, over 600 times brighter than forecast. As a result, great expectations are buzzing for this icy lump of cosmic detritus, with hopes it could become a stupendously bright object by the end of May.
But the brightening could also be a sign that the comet is ejecting a lot of material because it’s burning itself out, so grain of salt. But if keeps brightening at a good pace, it could be visible during the day in the northern hemisphere.
If Atlas manages to remain intact, some in the field have suggested it could grow from magnitude +1 to possibly -5. At the brightest extreme, it could be visible even during the day.
The location of the comet is also notable-unlike more recent comets, it will be best viewed in the Northern Hemisphere.
Chuck Ayoub recently captured the comet arcing across the night sky with his backyard astrophotography rig:
Oh I hope Comet ATLAS can keep it together. I vividly remember going outside in rural Wisconsin darkness to see the tail of Comet Hyakutake stretch halfway across the sky. One of the most amazing things I’ve ever seen.
Update: It looks as though Comet ATLAS will not be dazzling naked-eye observers later this spring — the comet seems to have broken into 3 or 4 pieces as it nears the Sun.
Although I guess Comet ATLAS is good news if you’re looking for signs of the apocalypse too. Pandemic: check. Bright new light in the sky: check.↩
The Curiosity Rover Captures a 1.8 Gigapixel Panorama of Mars
Late last year, NASA’s Curiosity rover took over a thousand photos of the Martian landscape while exploring a mountainside. NASA stitched the photos together and recently released this 1.8 gigapixel panorama of Mars (along with a mere 650 megapixel panorama, pictured above). Here’s a version you can pan and zoom:
And a narrated video of the panorama:
Both panoramas showcase “Glen Torridon,” a region on the side of Mount Sharp that Curiosity is exploring. They were taken between Nov. 24 and Dec. 1, when the mission team was out for the Thanksgiving holiday. Sitting still with few tasks to do while awaiting the team to return and provide its next commands, the rover had a rare chance to image its surroundings from the same vantage point several days in a row.
I like how NASA is casually suggesting that the rover is just kinda taking some vacation snaps while waiting on friends.