I can’t almost believe Pluto Day has arrived. While I’m writing this New Horizons, after a trip of nine years, is at T-3, 94,670 miles / 152356.6km away from performing the most awaited flyby of this start of the century, revealing a alien new world to our eyes.
Expectations have been building up in these last months, while the tiny yet powerful probe has beamed down to Earth increasingly detailed imagery (and it’s going to do so for another year or so. For the full sequence of LORRI images so far downloaded, see this).
The travel itself is an achievement on its own, with a spacecraft that is a marvel of technology and it’s the fastest launched so far (and, apart of scaring moment a few days when New Horizons entered in safe mode for unknown reasons, everything went admirably fine). Even before the much-anticipated today flyby, our knowledge about the planet and its cohort of moons has dramatically changed. For a start, we know better about its size, a notorious matter of contention. Pluto is larger than expected. According to the latest estimates, Pluto’s diameter amounts at 2370 km, 18.5% that of Earth’s (with Charon at 1208 km, 9.5% that of Earth’s).
Scientists have also find out surprising things about Pluto’s surface. It’s red (take that, Mars), with a rocky surface, an atmosphere and puzzling forms in its hemispheres. It has polar caps, for example, and a mysterious “heart” that rotates into full view now that New Horizons is approaching. And there are linear features too, probably cliffs, as well as a circular feature that could be an impact crater. The imagery from the flyby is going to add a lot more details to the (dwarf?) planet’s map.
Not only features of Pluto have been revealed in all their weirdness, but also Charon, its tidally-locked big moon, has proved a fascinating world.
Charon is a world of chasms and craters of various size. According to the latest data, the most pronounced chasm – in the southern hemisphere – is longer and far deeper than Earth’s Grand Canyon, while there’s a mysterious dark region near Charon’s north pole which measures more than 200 miles.
In an interesting video, ABC News have uploaded in a sequence all images received so far since January.
This is how the couple appeared to New Horizons in the latest imagery dowloaded, D-3 to the flyby. From NASA’s page: “Pluto and Charon display striking color and brightness contrast in this composite image from July 11, showing high-resolution black-and-white LORRI images colorized with Ralph data collected from the last rotation of Pluto. Color data being returned by the spacecraft now will update these images, bringing color contrast into sharper focus.”
As I write, NASA TV is broadcasting the historic moment online, which can be followed in streaming at this link. This is a day you want to stay tuned!
And what from tomorrow? First of all, getting ready to analyse the data New Horizons is going to send us, that will allow for even more information. Then, with history written, the mission goes on. New Horizons will fire its thrusters again and set its course towards a Kuiper Belt object, studying an unchartered area and (again) promising additional discoveries.
(Image Credits: NASA, when not otherwise stated)