Space Loot

Since the dawn of the Space Age, humanity has taken thousands of images of the Solar System. These images are publicly accessible, but they collect dust in obscure archives. My goal is to work with these images and give them the benefit of modern image processing. I also reblog images and interesting space stuff that catches my eye.

[venusianw]

Morning fog developing in the Memnonia region of Mars. This pair of color images was acquired by Viking Orbiter 1 about half an hour apart during a search for morning fogs. Contrary to initial expectations, where fog evaporated after sunrise, Viking 1 saw that fog *increased* after sunrise.

It was found that morning frost evaporated in the morning sunlight, then immediately recrystallized as tiny ice crystals in the colder atmosphere just above the surface. Unlike Earth, where fog forms overnight and is slowly burned off during morning, fog on Mars becomes denser after sunrise. The fog remains dense until the atmosphere warms above the freezing point of water ice, at which point it rapidly burns off.

This gif captures one of the first observations of this post-sunrise fog. This pair of color images was taken on July 24, 1976, about a month after Viking 1′s arrival at Mars.

Image Credit: NASA / JPL / Viking Project / Justin Cowart

[venusianw]

Jupiter’s volcanically active moon Io as seen by Voyager 1 on March 4, 1979. This image was taken a day before the spacecraft swooped past the moon at low altitude, revealing the numerous volcanic features that dot the world. 

At the 9 o’clock position, you can see a faint ghostly fountain. This is a massive eruptive plume from the volcano Pele that reaches nearly 250 km in height. Incredibly, this feature wasn’t noticed until a few days after the flyby, when Voyager navigation engineer (Linda Moribito noticed the plume in images looking back on Io after the flyby. (PDF warning) Only after the imaging team went back to look through their images was the plume noticed in this picture.

Image Credit: NASA / JPL / Voyager-ISS / Justin Cowart

[venusianw]

Curiosity at Furnace Flats - Sol 647

360 traverse documentation panorama taken on Sol 647 as Curiosity drove between The Kimberley and Hidden Valley waypoints.

[venusianw]

Comet 67P/Churyumov-Gerasimenko from a distance of 11km as seen through the Rosetta spacecraft’s OSIRIS imager. This is a mosaic of four separate frames.

Image Credit: ESA / Rosetta / MPS / OSIRIS Team / Justin Cowart

OSIRIS Team: MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA

[venusianw]

Wiggle gif of Comet 67P/Churyumov-Gerasimenko, using two images taken by the Rosetta spacecraft’s OSIRIS camera. These images were taken about 10 minutes apart. The parallax between images helps highlight the comet’s rugged topography. The concave cliff face at left is approximately 170m tall. In the background, the comet’s other lobe is rising from the horizon.

A full-size version of this gif can be found on Imgur.

Image Credit: ESA / Rosetta / MPS / OSIRIS Team / Justin Cowart

OSIRIS Team: MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA

[scrumpyfan43]

c’mon you make three of these and you only link to one?

another one

and a third (they’re both TOO MUCH GIF for Tumblr to handle)

[venusianw]

Wiggle gif of Comet 67P/Churyumov-Gerasimenko, using two images taken by the Rosetta spacecraft’s OSIRIS camera. These images were taken about 10 minutes apart. The parallax between images helps highlight the comet’s rugged topography. The concave cliff face at left is approximately 170m tall. In the background, the comet’s other lobe is rising from the horizon.

A full-size version of this gif can be found on Imgur.

Image Credit: ESA / Rosetta / MPS / OSIRIS Team / Justin Cowart

OSIRIS Team: MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA

[venusianw]

Phobos setting behind Mt. Sharp, sol 613. 

Interestingly, Phobos always sets in the *eastern* sky - it orbits Mars in a little less than a Martian day. An observer standing on the surface would see a crescent Phobos rise out of the western sky and set as a full moon in the eastern sky a few hours later. The irregular shape of Phobos is detectable in this image, as are hints of a few craters on its surface. 

This photo uses data taken on Sols 610 and 613. The original image of Phobos and Mt. Sharp was taken during dusk on Sol 613, but captured very little of the landscape surrounding the crater. I have supplemented this image by adding in some foreground imagery taken in the same location on Sol 610, and matched the lighting and coloration to the conditions of the Sol 613 image.

Image Credit: NASA / JPL / MSSS / Justin Cowart

[venusianw]

ChemCam RMI focus racking of target “Corkwood”, Curiosity sol 554.

Image Credit: NASA / JPL / LANL / Justin Cowart

[venusianw]

Gale Crater from Naukluft Plateau - Sol 1302

MastCam traverse documentation of the Naukluft Plateau area of Mars acquired by the Curiosity rover on Sol 1302 (April 6, 2016).

[venusianw]

Curiosity ChemCam Remote Micro-Imager (RMI) mosaic of stratigraphy at the base of Mt. Sharp on Sol 507. The ChemCam RMI is a grayscale imager designed to provide context information for ChemCam’s laser spectrometry system. This particular mosaic has been colorized using a lower resolution MastCam color image taken two sols earlier. 

RMI is normally targeted at nearby rocks, allowing the science team to study small microscopic features. However, on occasion, the RMI is pointed at long-distance targets. These targets allow geologists to build up a better understanding of Gale Crater from areas not on Curiosity’s traverse path, or in some cases, aid traverse planning months to years in advance.

Image Credit: NASA / JPL / LANL / Justin Cowart

[venusianw]

Curiosity’s ChemCam RMI imager focusing on the target “Clarabelle”, sol 371.

Image Credit: NASA / JPL / LANL / Justin Cowart

[venusianw]

Saturn’s tenuous D-ring early on March 11, 2016, as seen by the Cassini spacecraft. The D-ring is the innermost group of rings to Saturn, and are so faint that they weren’t discovered until the Voyager 1 in 1980. 

In late 2017, Cassini will plunge into Saturn’s atmosphere to prevent its radioactive power system from contaminating the moons Titan and Enceladus. The maneuvering done by the spacecraft will take it through the D-ring, allowing it to wring some difficult measurements of the D-ring’s chemical and dynamic characteristics.

This particular mosaic was acquired to better understand the density of material in different parts of the D-ring. This is necessary to determine the safest areas for Cassini’s swoops through the ring. Cassini will continue to study the D-ring through 2016, and provide spectacular ring views starting in 2017. The best is yet to come!

[venusianw]

Panorama of Chang’e 3′s landing site in Mare Imbrium. This probe, which landed on the Moon in December 2013, was China’s first soft landing on the Moon, and the first spacecraft of any sort to make a soft landing on the Moon since 1976. Soon after arrival, the lander deposited a small rover named Yutu. In this panorama, acquired about 3 days after landing, Yutu has driven partway around the lander. Before a mechanical malfunction stopped Yutu’s exploration of the lunar surface, it would travel to Loong Yan (Dragon Rock, the large pointy rock at bottom center) and back to the lander. The last transmission from Yutu was in March 2015, but the Chang’e 3 lander continues to function, mostly performing astronomical observations with its ultraviolet telescope.

Image Credit: Chinese Academy of Sciences / China National Space Administration / The Science and Application Center for Moon and Deepspace Exploration / Justin Cowart

[venusianw]

Departing Enceladus

On December 19, 2015, the Cassini mission made its final close flyby of Saturn’s moon Enceladus. At closest approach, the spacecraft was only 5,000 km (3,100 mi) from the tectonically active moon. Shortly after closest approach, Cassini turned around and captured this image of a crescent Enceladus, with the cloud tops of Saturn in the background.

Six relatively distant flybys remain scheduled in the last two years of the Cassini mission. The closest will occur in November 2016 at a range of 22,000 km (14,000 mi), while all others will be further than 72,000 km (48,000 mi). As a result, this is the final image of Enceladus taken at such high resolution until the next mission to Saturn arrives, whenever that may be.

Image Credit: NASA / JPL / Cassini-SSI / Justin Cowart

[biopocalypse]

I am frankly troubled by the number of people on tumblr who think the fact that science is subject to human bias is a Profound Activist Discovery.  A human endeavor is subject to human folly…incredible, right?

And FYI, it doesn’t make promoting pseudoscience acceptable.

[venusianw]

I think a point to be made is that science education isn’t great at teaching how and why bias creeps into science. We’re wired to approve of an argument we like, but less well-equipped to actually dig into the data backing it up. Not many science classes really explore that or even mention it.

One of the best classes I’ve ever taken gave us a paper published in Science about detecting geochemical evidence of eukaryotic life 3.5 billion years ago, and asked us to write a couple paragraphs with our thoughts about it. Nearly 90% of the class accepted it after a thorough read and a quick skim of the included data (myself included). But a couple students dug deeper and found a few things that seemed out of place. There were minor inconsistencies in the data, and one student who was more familiar with the kinds of labwork used in the experiment noted places where contamination could have crept in. And all of those students, after noting the inconsistencies, dug deeper and discovered that the paper had been retracted a year later.

That was the first time that my own lazy thinking had been highlighted. For most of my college career, I had been handed papers by professors to read and absorb. The whole time, we’d never been taught to pick over what we’ve been handed. It makes me wonder how many scientists have been trained to implicitly trust peer review in name brand journals as a filter for good information, and not double check the argument for themselves.

But anyway, yeah. We forget that science isn’t fact, it’s a process of learning and interpreting facts. It’s inherently prone to cognitive bias, both conscious and subconscious. We just don’t do a good job of making sure that budding scientists learn that and constantly guard themselves against it.

[venusianw]

Earth and Moon from Mariner 10 on November 6 and November 5, respectively.

Mariner 10 was the last of the Mariner spacecraft, but it accomplished a huge number of space firsts. Launched on November 3, 1973, it was destined to end up at Mercury. But getting there requires a lot of energy, and a direct launch to Mercury transfer was impossible with available rocketry. Success meant trying out new techniques for making every last bit of energy count.

One of these new techniques took advantage of the Olberth Effect. When a rocket travels faster, its fuel use is more efficient due to its kinetic energy. (After all, kinetic energy is proportional to the square of an object’s velocity.) To make use of this effect, it was launched into a highly elliptical orbit around the Earth, so that when it returned to the vicinity of low Earth orbit, it would be traveling *really* fast. A second rocket burn at the lowest altitude would give the rocket an additional kick.

The image of the Earth and Moon were acquired while Mariner 10 was still in orbit around Earth. Engineers decided to use time in Earth orbit to test out the spacecraft’s cameras, acquiring a huge number of photographs of the Earth and Moon.

The image of Earth is a three frame mosaic capturing the western Pacific Ocean. The coast of Australia can be seen poking out from the clouds near the bottom of the image.

The image of the Moon captures most of the lunar farside’s eastern hemisphere. The spectacular ringed impact crater at center is Mare Moscoviense, while the slightly smaller crater just to its upper right is Mendeleev. The partially flooded crater Tsiolkovsky is near the 1 o’clock position. Some of the Mare features more familiar to us Earthlings are at the three o’clock position. The largest is Mare Crisium, and above it are Mare Marginis and Mare Smythii, both of which are very nearly unobservable from Earth.

[venusianw]

Comet Catalina (C/2013 US10) on the morning of December 3, 2015. I took this photo with a Nikon D5100 and 70-300 mm zoom telephoto lens at 200 mm.

Comet Catalina is a first-time visitor to the inner Solar System. It hails from the Oort Cloud, a vast reserve of icy lumps, some of which occasionally get nudged inwards by a passing star. The path that Comet Catalina is taking suggests that it will be millions of years before the comet returns, if at all.

Catalina sports two tails shooting away from the icy green coma (a cloud of poisonous cyanogen and diatomic carbon gases), a bright yellow dust tail (pointing down) and a faint blue ion tail (pointing up). It’s often said that a comet’s tails point directly away from the Sun, but this is really only true in the case of the ion tail. While dust is being pushed away from the comet in the opposite direction of the Sun, it is actually spreading out along the comet’s orbital path. In this case, the viewing geometry from the Earth is such that the dust tail looks more like it’s pointing towards the Sun!

Over the next month, the Earth will be moving closer to the comet, making it larger and brighter in our skies. On December 7th, it passes close to Venus from our point of view, sharing the same binocular field with it and the waning crescent moon. On New Years Day, it will pass only half a degree (one moon width) from the bright star Arcturus. Although it probably won’t turn into a spectacular visual sight, it will continue providing gorgeous photographic views for a while to come.