Category: Space Exploration

Almost everyone is familiar with this view we get of the Orion constellation:

But what most people don't realize is the varying distances everything in that constellation is from Earth. Even I'd believed that the three belt stars were somewhat near each other…

That bright spot in the lower right is Earth.

…if we were told (not that they actually would, of course) that all those fragments were on a direct collision course with Earth, I wouldn't be the least bit surprised.

What would it look like to approach Saturn in a spacecraft? One doesn't have to just imagine—the Cassini spacecraft did just this in 2004, recording thousands of images along the way, and hundreds of thousands more since entering orbit. Some of Cassini's early images have been digitally tweaked, cropped, and compiled into the featured inspiring video which is part of a larger developing IMAX movie project named In Saturn's Rings. In the concluding sequence, Saturn looms increasingly large on approach as cloudy Titan swoops below. With Saturn whirling around in the background, Cassini is next depicted flying over Mimas, with large Herschel Crater clearly visible. Saturn's majestic rings then take over the show as Cassini crosses Saturn's thin ring plane. Dark shadows of the ring appear on Saturn itself. Finally, the enigmatic ice-geyser moon Enceladus appears in the distance and then is approached just as the video clip ends. After more than a decade of exploration and discovery, the Cassini spacecraft ran low on fuel in 2017 was directed to enter Saturn's atmosphere, where it surely melted.

And I will never see another craft visit Saturn in my lifetime. This was truly a once-in-a-lifetime occurrence.

From NASA:

Other Juno science results released today include that the massive cyclones that surround Jupiter's north and south poles are enduring atmospheric features and unlike anything else encountered in our solar system. The findings are part of a four-article collection on Juno science results being published in the March 8 edition of the journal Nature.

"These astonishing science results are yet another example of Jupiter's curve balls, and a testimony to the value of exploring the unknown from a new perspective with next-generation instruments.  Juno's unique orbit and evolutionary high-precision radio science and infrared technologies enabled these paradigm-shifting discoveries," said Scott Bolton, principal investigator of Juno from the Southwest Research Institute, San Antonio. "Juno is only about one third the way through its primary mission, and already we are seeing the beginnings of a new Jupiter."

North Vortex

South Vortex

…orgasmed a little upon seeing these photos from Cassini. Saturn's rings, up close and personal:

It pains me that after this year, there will be no new pictures of Saturn. There are no plans to return to the planet during the remainder of my foreseeable lifetime. I'm glad I was alive when I was to witness this in real time.

I know it would risk losing control of the spacecraft completely, but after seeing these photos shot from still thousands of miles away, can you imagine what we'd see if Cassini flew through the rings on its final orbit around the planet?

NASA's JUNO probe is in orbit around Jupiter and is sending back some absolutely amazing views of the gas giant. We're seeing the planet in ways we've never seen before and in unprecedented detail.

This view from NASA's Cassini spacecraft is the sharpest ever taken of belts of the features called propellers in the middle part of Saturn's A ring.

The propellers are the small, bright features that look like double dashes, visible on both sides of the wave pattern that crosses the image diagonally from top to bottom.

The original discovery of propellers in this region in Saturn's rings (see Four Propellers, Propeller Motion​, Locating the Propellers​) was made using several images taken from very close to the rings during Cassini's 2004 arrival at Saturn. Those discovery images were of low resolution and were difficult to interpret, and there were few clues as to how the small propellers seen in those images were related to the larger propellers Cassini observed later in the mission (for example 'Earhart' Propeller in Saturn's A Ring, Cassini Targets a Propeller in Saturn's A Ring​, and Bleriot Propeller Close-up​).

This image, for the first time, shows swarms of propellers of a wide range of sizes, putting the ones Cassini observed in its Saturn arrival images in context. Scientists will use this information to derive a "particle size distribution" for propeller moons, which is an important clue to their origins.

Maybe the next time we visit—assuming our species survives Donald Trump—we'll send a rover…or a flotilla of boats.

From NASA:

NASA's Cassini spacecraft has had its last close brush with Saturn's hazy moon Titan and is now beginning its final set of 22 orbits around the ringed planet.

The spacecraft made its 127th and final close approach to Titan on April 21 at 11:08 p.m. PDT (2:08 a.m. EDT on April 22), passing at an altitude of about 608 miles (979 kilometers) above the moon's surface.

Cassini transmitted its images and other data to Earth following the encounter. Scientists with Cassini's radar investigation will be looking this week at their final set of new radar images of the hydrocarbon seas and lakes that spread across Titan's north polar region. The planned imaging coverage includes a region previously seen by Cassini's imaging cameras, but not by radar. The radar team also plans to use the new data to probe the depths and compositions of some of Titan's small lakes for the first (and last) time, and look for further evidence of the evolving feature researchers have dubbed the "magic island."

"Cassini's up-close exploration of Titan is now behind us, but the rich volume of data the spacecraft has collected will fuel scientific study for decades to come," said Linda Spilker, the mission's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.

We're going to miss you, Cassini.

And considering there are no plans to send any more probes to Saturn during my lifetime I'm incredibly lucky to have lived during this mission.

Cassini Completes Final Close Enceladus Flyby

NASA's Cassini spacecraft has begun transmitting data and images from the mission's final close flyby of Saturn's active moon Enceladus. Cassini passed Enceladus at a distance of 3,106 miles (4,999 kilometers) on Saturday, Dec. 19, at 9:49 a.m. PST (12:49 p.m. EST).

After revealing Enceladus' surprising geologic activity in 2005, Cassini made a series of discoveries about the material gushing from warm fractures near its south pole. Scientists announced strong evidence for a regional subsurface sea in 2014, revising their understanding in 2015 to confirm that the moon hosts a global ocean beneath its icy crust.

"Not only is the Universe stranger than we imagine, it is stranger than we can imagine." ~ Sir Arthur Eddington, English Astronomer (1882-1944)

NASA's New Horizons spacecraft spied several features on Pluto that offer evidence of a time millions or billions of years ago when—thanks to much higher pressure in Pluto's atmosphere and warmer conditions on the surface—liquids might have flowed across and pooled on the surface of the distant world.

This feature appears to be a frozen, former lake of liquid nitrogen, located in a mountain range just north of Pluto's informally named Sputnik Planum. Captured by the New Horizons' Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Pluto on July 14, 2015, the image shows details as small as about 430 feet. At its widest point the possible lake appears to be about 20 miles across.

A lake of liquid nitrogen…now frozen. Mind blown.