Category Archives: Pluto
They’re here and they’re from outer space! The U.S. Postal Service has two new sets of Forever® stamps based on NASA’s exploration of the Solar System: the Views of Our Planets and Pluto—Explored! series, both of which become available for purchase on May 31, 2016.
Designed by Antonio Alcalá, the Views of Our Planets stamps feature eight images of the major planets in the Solar System, as seen by various spacecraft over the past three decades. Pluto—Explored! highlights an extended-color image of the distant dwarf planet and a rendering of the New Horizons spacecraft, which gave us our first good look at Pluto in July 2015.
The last stamp to feature Pluto was a 29-cent version issued in 1991, which showed a featureless tan orb with the words “not yet explored” beneath it… we can now officially call that version obsolete!
Both sets are Forever stamps, which means they are always good as first-class postage for 1 oz. envelopes, whatever the current postage price may be. You can purchase
both in collectible sheets at your local U.S. Post Office or online here.
*Note: the Pluto stamps are only available online.
Discovered in June 2005, distant Pluto’s outermost moon Hydra it thought to have formed during the same collision four billion years ago that created the Pluto-Charon system that we see today. Yet despite its age this 31-mile (50-km) -long moon appears remarkably clean and bright, as witnessed by New Horizons during its close pass through the Pluto system in July 2015.
Hockey fans take note: future visitors to Pluto may want to bring along their sticks and skates—the distant planet may harbor some pristine ice in the form of frozen ponds and lakes! (NASA might have to work on a lightweight, collapsible Zamboni first though.)
We could be calling it Cloudgate—”leaked” information from internal emails identifying structures in Pluto’s already hazy atmosphere that could very well be clouds, based on a March 4 article in New Scientist.
The image above shows sections of a New Horizons image attached to an email sent by SwRI scientist John Spencer, in which he noted particularly bright areas in Pluto’s atmosphere. “In the first image an extremely bright low altitude limb haze above south-east Sputnik on the left, and a discrete fuzzy cloud seen against the sunlit surface above Krun Macula (I think) on the right,” he wrote.
Whether you want to call it a planet, dwarf planet, Kuiper Belt Object, or some or none of the above, there’s no denying that Pluto and its family of moons are true curiosities in the Solar System. Not only does little Pluto have one moon — Charon — that’s so massive in comparison that they both actually orbit each other around a central point outside the radius of either (if you feel like adding “binary” to whatever term you prefer to use, go right ahead) but it also has four other smaller moons in orbit that kinda sorta break the rules of how moons are “supposed to” behave.
When New Horizons made its close pass pf Pluto on July 14, 2015, it did much more than just take pretty pictures; it was also scanning the planet with a suite of science instruments designed to determine the nature of its surface, atmosphere, composition, and other key characteristics. One of these instruments was the Linear Etalon Imaging Spectral Array (LEISA), an infrared scanner that can detect the unique molecular “fingerprints” of particular elements and compounds like methane, nitrogen, carbon monoxide… and water (one of our favorites!)
At first the data returned from LEISA showed only a surprisingly small amount of water ice across Pluto’s surface. But that was water ice in its pure form; when researchers took into consideration ice containing a mixture of water and other materials they found a much more widespread distribution across the surface area visible to New Horizons.