Cassini Sees Earth and Moon Through Saturn’s Rings

NASA/JPL-Caltech/Space Science Institute

NASA’s Cassini mission sure has a knack for putting stuff into perspective — and this most recent view from Saturn orbit is no different. That dot in the center of the image isn’t a dud pixel in Cassini’s camera CCD. That’s us. All of us. Everyone.

To quote Carl Sagan:

“Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives…”

Sagan wrote that passage in his book “Pale Blue Dot: A Vision of the Human Future in Space” when reflecting on the famous “Pale Blue Dot” image that was beamed back to Earth by NASA’s Voyager 1 spacecraft in 1990. That’s when the mission returned a profound view of our planet from a distance of 3.7 billion miles (or 40.5AU) as it was traveling through the solar system’s hinterlands, on its way to interstellar space. Since then, there’s been many versions of pale blue dots snapped by the armada of robotic missions around the solar system and Cassini has looked back at us on several occasions from its orbital perch.

Now, just before Cassini begins the final leg of its Saturnian odyssey, it has again spied Earth through a gap between the gas giant’s A ring (top) and F ring (bottom). In a cropped and enhanced version, our moon is even visible! The image is composed of many observations captured on April 12, stitched together as a mosaic when Saturn was 870 million miles (roughly 9.4AU) from Earth.

On April 20 (Friday), Cassini will make its final flyby of Titan, Saturn’s largest moon, using its gravity to fling itself through Saturn’s ring plane (on April 26) between the innermost ring and the planet’s cloudy upper atmosphere, revealing a view that we’ve never before seen. For 22 orbits, Cassini will dive into this uncharted region, possibly revealing new things about Saturn’s evolution, what material its rings contain and incredibly intimate views of its atmosphere.

This daring maneuver will signal the beginning of the end for this historic mission, however. On Sept. 15, Cassini will be intentionally steered into Saturn’s atmosphere to burn up as a human-made meteor. It is low in fuel, so NASA wants to avoid the spacecraft from crashing into and contaminating one of Saturn’s potentially life-giving moons — Titan or Enceladus.

So, appreciate every image that is captured by Cassini over the coming weeks. The pictures will be like nothing we’ve seen before of the ringed gas giant, creating a very bittersweet phase of the spacecraft’s profound mission to Saturn.


Crop Circles Do Not Predict Solar Storm on July 7th…

Stunning art, UFOs not included (© Lucy Pringle)
Stunning art, UFOs not included (© Lucy Pringle)

Alternative title: “Jumping to Conclusions and Bullshit”

Crop circles are amazing. They are, quite literally, works of art. And like all other known forms of art, they are constructed by people with time on their hands. No UFOs have been braiding our crops, no aliens have been playing let’s-confuse-the-stoopid-humans-with-this-cryptic-message-we-travelled-hundreds-of-light-years-to-deliver. Crop circles are made by hoaxers and enthusiasts.

So yesterday, I read a terribly fascinating, yet terribly painful article that seamlessly combines three disparate facts to arrive at a terribly flawed conclusion: a coronal mass ejection (CME) will hit us on July 7th, possibly causing global damage, according to a crop circle prediction.

This may seem a little shocking, considering this equivalent of a micro-doomsday is only two days from now, but the “Exopolotics Examiner” Dr. Michael Salla discusses it with great excitement:

The Alert is for Sunspot 1024 which suddenly appeared on July 3 and 4 […] It typically takes CMEs, traveling at around a million miles per hour, three to four days to reach the Earth. So if Sunspot 1024 does generate CMEs towards the Earth, they would arrive right on the predicted date of July 7.

Apparently, we now have an infallible space weather prediction method. Sunspot 1024 could generate a CME directed toward Earth, therefore fulfilling the prediction that we are going to get hit by a CME in two days. Amazing right? Obviously Salla is referring to the work of a solar physicist, with a new hi-tech computer simulation, or with access to cutting-edge observational data. Wow, it looks like we have found the Holy Grail of sunspot characterization methods!

(Guess again)

Actually, the July 7th prediction is purely based on crop circles at Milk Hill, in Wiltshire, UK. How do we know these flattened fields of corn predict a CME? Actually, they don’t. Even the crop circle experts make no convincing connection with crop circles and the Sun, apart from pointing out that the patterns resemble an orrery — but even if it is an orrery, the corn has been flattened by a team of hoaxers, they could make it mean anything. (I’m still waiting for a massive Micky Mouse crop circle.)

Although I find all this highly entertaining, the thing that made me laugh the most was the point that the Milk Hill patterns were made in “3 Phases.” However, looking at the incredibly beautiful design of that thing, it’s little wonder the aliens had to build the design in shifts. After all, extraterrestrials need tea-breaks too… perhaps their little feet got tired stomping all that corn… or perhaps it was constructed by slacking crop circle hoaxers who couldn’t get it all done in one night?

My money is on the latter.

So, there is a dubious link between the crop circle and the Sun (apart from ‘it faces that way,’ directly along the tractor tracks… hmm, interesting), what could Salla be talking about? Oh that’s it! The Earth’s magnetosphere has a hole in it! Hell, dig your lead-lined bomb shelters now!

Now this is one point I’m actually a little annoyed about. Apparently Dr. Salla is also qualified in solar-terrestrial physics, as he seems to dredge up some pretty compelling science recently published by NASA. Salla says:

Importantly, scientists will be able to directly study the impacts of large amounts of solar plasma penetrating a breach in the magnetosphere first reported by NASA scientists in December 2008 […] If the interpretations of crop circle researchers are correct, then we will shortly directly observe the impact of solar energy from CMEs passing through the magnetosphere breach. –Dr Salla (emphasis not added by me, used for dramatic effect I suspect).

Now this is good stuff, perhaps this guy is on to something. In summary:

  1. The Milk Hill crop circle predicts a solar storm on July 7th (but it’s not very clear where in the corn this is printed).
  2. An active sunspot has appeared at a high latitude on the solar surface (this is true, although only B Class solar flares have been detected… not in Earth-killing leagues I’m afraid).
  3. This sunspot could generate an Earth-directed CME (this is true, again, but the odds are pretty damn low).
  4. The CME will hit us on July 7th (read #3).
  5. Now that NASA has detected a hole in our magnetosphere, deadly solar particles could penetrate our atmosphere!

In other words, Salla has strung together some dubious “signs” from a crop circle, tied it into this new sunspot, gotten all excited that it could generate some pretty feeble CMEs, somehow assumed they will be Earth-directed and then chucked in a very incorrect opinion as to what this “hole in the magnetosphere” means.

Although the magnetospheric breach is certainly an amazing discovery — made by the Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites in 2008 — I think Salla misses the point. The magnetospheric breach hasn’t just appeared, it wasn’t caused by human activity (like the hole in the ozone layer, which I think he thinks this is), it’s always been there in some way, shape or form.

NASA’s five THEMIS spacecraft have discovered a breach in Earth’s magnetic field ten times larger than anything previously thought to exist. Solar wind can flow in through the opening to “load up” the magnetosphere for powerful geomagnetic storms. But the breach itself is not the biggest surprise. Researchers are even more amazed at the strange and unexpected way it forms, overturning long-held ideas of space physics.NASA release.

Obviously overcome with the NASA terminology “giant breach,” Salla assumes this is a new hole in the magntosphere leaving us open to the ravages of the Sun. Actually it doesn’t, it’s simply an observation of a previously unknown piece of magnetospheric dynamics. Yes, the breach is linked with solar storms and the aurora, but there’s every likelihood this phenomenon has always existed, even when the Earth’s magnetic field was battered by X-class solar flares and jumbo CME’s during the last solar maximum (are we still here? Yes, I think we are). To think we are going to even notice a make-believe low-energy CME produced by a feeble region of the Sun generating B-class solar flares is laughable.

So the physics is flawed, the prediction is totally far-fetched, and apparently you need a PhD in exopolitics to understand how crop circles come into it. It’s just a fear-mongering article that is becoming all too common on the Examiner these days.

No, this is another huge FAIL for the Examiner… where are all the Skeptical, Science and Common Sense Examiners?

Thank you @mactavish for reminding me to finish this article!

Geodesy and GOCE: Astrocast.TV with Bente Lilja Bye

In the first episode of A Green Space — A Green Earth at Astrocast.TV, my friend and astrophysicist Bente Lilja Bye gives a superb overview about the Gravity field and steady-state Ocean Circulation Explorer (GOCE) that was finally launched in March. It’s a captivating show, detailing the history and science behind the study of geodesy (the gravitational field, shape and rotation of the Earth).

You may not be familiar with geodesy, but it is critical to advancing our understanding of the planet we live on. For example, GOCE observations could aid prediction techniques for earthquakes, or refine GPS data; suddenly geodesy has a very real and immediate relevance to us on the ground.

Be sure to check out the video below, it’s a very slick production. Great job Bente!

High Resolution Earth Rise Video by Kaguya (SELENE)

A little bit of beautiful - the Earth rises over the lunar horizon (JAXA)
A little bit of beautiful - the Earth rises over the lunar horizon (JAXA)

Using its High Definition Television (HDTV) camera, the Japanese lunar probe Kaguya captured an astounding video of the Earth slowly rising above the lunar horizon. The video was actually released at the start of this month, but it has only just come to my attention. The video was recorded on September 30th, as the probe orbited 100 km above the Moon. Stunning.

See the tele-view “Full-Earth Rise” »

See the wide-angle Earth-set »

Read more about “Full-Earth Rise” »