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!”

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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!