New Horizons LORRI image comparison of Pluto April 12th (left) and May 8th, 2015 (right) at the stated distances.
As it draws closer to dwarf planet Pluto* and its retinue of five known moons (Charon, Hydra, Nix, Styx, and Kerberos), NASA's and humanity's awesome, intrepid, wonderful little space probe New Horizons already is doing us proud .
New Horizons is doing this by showing us at long-range the fact that Pluto has marked surface features of varying brightness including, quite possibly, a northern polar ice cap of whatever composition (as if anything as cold as Pluto needed an ice cap!).
New Horizons LORRI image comparison of Pluto April 15th (left) and May 10th, 2015 (right) at the stated distances.
*As an important aside, Pluto may now be a dwarf planet and "just" the closest, largest Kuiper Belt object and Trans-Neptunian Object, but forever in the hearts of those of us who came of age in the latter half of the 20th Century, Pluto forever will be part of the "Canonical 9" planetary bodies of our Solar System. The New Horizons fly-by exploration this summer marks the closing chapter of the first epoch of unmanned planetary probe exploration of our Solar System.
NASA has released a series of comparison images taken in mid-April and then in mid-May showing these as-yet-blurry features on Pluto. These images are included in this entry as the first three -- two above and the one directly below.
New Horizons LORRI image comparison of Pluto April 16th (left) and May 12th, 2015 (right) at the stated distances.
There is actually an animation of the three images above that make show the features of Pluto more compelling. I found at this site (link embedded): New Horizons' Latest Pluto Pics Reveal a Complex and Varied Surface.
(The headline possessive is misspelled; I've corrected it here to make the possessive New Horizons' although I suppose one could make it "New Horizons's. NASA seems to prefer the former (see below).)
New Horizons with instruments labeled.
Yes, Ralph and Alice. I love that fact.
"You're going to the Moon, Alice! Ehhh! Bang! Zoom!"
The full NASA caption (adapted slightly) to the three comparison images reads:
These images show Pluto in the latest series of New Horizons Long Range Reconnaissance Imager (LORRI) photos, taken May 8-12, 2015, compared to LORRI images taken one month earlier. In the month between these image sets, New Horizons' distance to Pluto decreased from 68 million miles (110 million km) to 47 million miles (75 million km), as the spacecraft speeds toward a close encounter with the Pluto system in mid-July.
The April images are shown on the left, with the May images on the right. All have been rotated to align Pluto's rotational axis with the vertical direction (up-down), as depicted schematically in the center panel. Between April and May, Pluto appears to get larger as the spacecraft gets closer, with Pluto's apparent size increasing by approximately 50 percent. Pluto rotates around its axis every 6.4 Earth days, and these images show the variations in Pluto's surface features during its rotation.
These images are displayed at four times the native LORRI image size, and have been processed using a method called deconvolution, which sharpens the original images to enhance features on Pluto. Deconvolution can occasionally add "false" details, so the finest details in these pictures will need to be confirmed by images taken from closer range in the next few weeks. All of the images are displayed using the same linear brightness scale.
Pluto and Charon in color as seen by the Ralph imager, New Horizons, April 9, 2015.
As of now, we are just 45 days and 54.1 million kilometers to the closest approach of Pluto and Charon on July 14, 2015.
As a final thought to New Horizons ...
Dear New Horizons, Intrepid Pioneer So Far From Home,
You may be by yourself hurtling across the farthest edges of the known Solar System where the Sun is but a dazzling point of light in the endless black night of starry space; Jupiter and Saturn are bright, steady stars; and Planet Earth is but a very dim bluish dot (probably lost in the glare of the Sun), but please know little one that you are not alone.
We're with you, seeing what you see, connected to you across that yawning void of 3 billion miles not just through technology but in mind and spirit. Where you go, we go.
GO, NEW HORIZONS, GO!!