Pluto and Charon are coming into focus as New Horizons‘ probe nears fly-by. Here are the latest and sharpest images so far:

Pluto and Charon: New Horizons’ Dynamic Duo

They’re a fascinating pair: Two icy worlds, spinning around their common center of gravity like a pair of figure skaters clasping hands. Scientists believe they were shaped by a cosmic collision billions of years ago, and yet, in many ways, they seem more like strangers than siblings.

A high-contrast array of bright and dark features covers Pluto’s surface, while on Charon, only a dark polar region interrupts a generally more uniform light gray terrain. The reddish materials that color Pluto are absent on Charon. Pluto has a significant atmosphere; Charon does not. On Pluto, exotic ices like frozen nitrogen, methane, and carbon monoxide have been found, while Charon’s surface is made of frozen water and ammonia compounds. The interior of Pluto is mostly rock, while Charon contains equal measures of rock and water ice.

“These two objects have been together for billions of years, in the same orbit, but they are totally different,” said Principal Investigator Alan Stern of the Southwest Research Institute (SwRI), Boulder, Colorado.

Charon is about 750 miles (1200 kilometers) across, about half the diameter of Pluto—making it the solar system’s largest moon relative to its planet. Its smaller size and lower surface contrast have made it harder for New Horizons to capture its surface features from afar, but the latest, closer images of Charon’s surface show intriguing fine details.

Newly revealed are brighter areas on Charon that members of the mission’s Geology, Geophysics and Imaging team (GGI) suspect might be impact craters. If so, the scientists would put them to good use. “If we see impact craters on Charon, it will help us see what’s hidden beneath the surface,” said GGI leader Jeff Moore of NASA’s Ames Research Center. “Large craters can excavate material from several miles down and reveal the composition of the interior.”

In short, said GGI deputy team leader John Spencer of SwRI, “Charon is now emerging as its own world. Its personality is beginning to really reveal itself.”

Here’s the latest update on the New Horizons mission:

—

Here are timelines of events from now till July 14th when the New Horizons probe passes by Pluto and several days after:

• Updated Television Coverage, Media Activities for Pluto Flyby – NASA
• What to expect when you’re expecting a flyby: Planning your July around New Horizons’ Pluto Pictures (version 2) | The Planetary Society – Updated on July 8th.

—

Add Pluto to your Google Earth program:

• A Google Earth overlay of New Horizons’ Latest Map of Pluto. – New Horizons
• Explore Pluto in Google Earth! – The Planetary Society

The images of Pluto from the New Horizons probe get better day by day. Here is the latest:

A ‘Heart’ from Pluto as Flyby Begins

After a more than nine-year, three-billion-mile journey to Pluto, it’s showtime for NASA’s New Horizons spacecraft, as the flyby sequence of science observations is officially underway.

In the early morning hours of July 8, mission scientists received this new view of Pluto—the most detailed yet returned by the Long Range Reconnaissance Imager (LORRI) aboard New Horizons. The image was taken on July 7, when the spacecraft was just under 5 million miles (8 million kilometers) from Pluto, and is the first to be received since the July 4 anomaly that sent the spacecraft into safe mode.

This view is centered roughly on the area that will be seen close-up during New Horizons’ July 14 closest approach. This side of Pluto is dominated by three broad regions of varying brightness. Most prominent are an elongated dark feature at the equator, informally known as “the whale,” and a large heart-shaped bright area measuring some 1,200 miles (2,000 kilometers) across on the right. Above those features is a polar region that is intermediate in brightness.

“The next time we see this part of Pluto at closest approach, a portion of this region will be imaged at about 500 times better resolution than we see today,” said Jeff Moore, Geology, Geophysics and Imaging Team leader of NASA’s Ames Research Center. “It will be incredible!”

===

A scientist in the New Horizons mission, Matt Hill, writes about what plasma science can tell us about Pluto : Science Shorts: A space physicist’s view of Pluto – New Horizons –

Yes, but why would a space physicist study Pluto?

After all, at Pluto we don’t have much to go on. We don’t expect a significant magnetic field, since we don’t believe there is a molten metal core, but mounting evidence demonstrates that the atmosphere of Pluto is large (if tenuous by Earthly standards) and releasing a significant, steady rate of material.  These neutrally charged, Plutonian gas particles from its atmosphere are expected to interact with the impinging, highly charged solar wind and solar photons resulting in freshly charged “pickup ions” that, depending on their kinetic energy, are detectable by the Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) time-of-flight mass spectrometer on board New Horizons.

These pickup ions can help tell us about the rate at which Pluto loses its atmosphere, but also Pluto’s production of these pickup ions provides us with the opportunity to study the pickup ions themselves at the moment of their creation. The physics of how they are accelerated and transported is not well understood (although there are many theories). So when New Horizons races through Pluto’s atmosphere and PEPSSI detects the ions there, I will be looking out for pickup ions and hoping to learn how the pickup ions get their energy and how they exit the Pluto system. Only a little more patience is needed—it all happens next month!

New images of Pluto taken by the New Horizons probe have just been released:

Latest Images of Pluto from New Horizons

These are the most recent high-resolution views of Pluto sent by NASA’s New Horizons spacecraft, including one showing the four mysterious dark spots on Pluto that have captured the imagination of the world. The Long Range Reconnaissance Imager (LORRI) obtained these three images between July 1 and 3 of 2015, prior to the July 4 anomaly that sent New Horizons into safe mode.

Click for larger image.

The left image shows, on the right side of the disk, a large bright area on the hemisphere of Pluto that will be seen in close-up by New Horizons on July 14. The three images together show the full extent of a continuous swath of dark terrain that wraps around much of Pluto’s equatorial region. The western end of the swath (right image) breaks up into a series of striking dark regularly-spaced spots, each hundreds of miles in size, which were first detected in New Horizons images taken in late June. Intriguing details are beginning to emerge in the bright material north of the dark region, in particular a series of bright and dark patches that are conspicuous just below the center of the disk in the right image. In all three black-and-white views, the apparent jagged bottom edge of Pluto is the result of image processing. The inset shows Pluto’s orientation, illustrating its north pole, equator, and central meridian running from pole to pole.

The color version of the July 3 LORRI image was created by adding color data from the Ralph instrument gathered earlier in the mission.

Click for larger image.

Credit: NASA/JHUAPL/SWRI