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New Horizons spacecraft sweeps past Pluto

New Horizons is alive and well and beyond the Pluto system. On Wednesday, scientists began releasing close-up images of geology on this distant ice world.

View larger. | Ice mountains on Pluto. Close-up image of a region near Pluto’s equator - at the bottom of the heart region, which is now being called Tombaugh Regio. These mountains - which are

View larger. | Ice mountains on Pluto. Close-up image of a region near Pluto’s equator – at the bottom of the heart region, which is now being called Tombaugh Regio. These mountains – which are “youthful” scientists say – rise as high as 11,000 feet (3,500 meters) above the surface of Pluto. Image taken about 1.5 hours before New Horizons closest approach to Pluto, when the craft was 478,000 miles (770,000 kilometers) from the surface of the planet. The image easily resolves structures smaller than a mile across. Image Credit: NASA-JHUAPL-SwRI

NASA’s New Horizons spacecraft has reached its closest point to Pluto, and now is heading … beyond.

After a decade-long journey through our solar system, New Horizons made its closest approach to Pluto Tuesday (July 14, 2015), about 7,750 miles above the surface – roughly the same distance from New York to Mumbai, India – making it the first-ever space mission to explore a world so far from Earth.

Per the plan, the spacecraft on Tuesday was in data-gathering mode and not in contact with flight controllers on Tuesday, but by mid-day Wednesday scientists were gathered again with press, talking about first results from the Pluto mission. The mountains likely formed no more than 100 million years ago — mere youngsters relative to the 4.56-billion-year age of the solar system — and may still be in the process of building, said Jeff Moore of New Horizons’ Geology, Geophysics and Imaging Team (GGI).

That suggests the close-up region, which covers less than one percent of Pluto’s surface, may still be geologically active today.

Moore and his colleagues base the youthful age estimate on the lack of craters in the image above. Like the rest of Pluto, this region would presumably have been pummeled by space debris for billions of years and would have once been heavily cratered — unless recent activity had given the region a facelift, erasing those pockmarks. Moore said in a statement from NASA:

This is one of the youngest surfaces we’ve ever seen in the solar system.

Unlike the icy moons of giant planets, Pluto cannot be heated by gravitational interactions with a much larger planetary body. Some other process must be generating the mountainous landscape. GGI deputy team leader John Spencer of the Southwest Research Institute in Boulder said:

This may cause us to rethink what powers geological activity on many other icy worlds.

The mountains are probably composed of Pluto’s water-ice “bedrock.”

Although methane and nitrogen ice covers much of the surface of Pluto, these materials are not strong enough to build the mountains. Instead, a stiffer material, most likely water-ice, created the peaks. Deputy GGI lead Bill McKinnon of Washington University, St. Louis, said:

At Pluto’s temperatures, water-ice behaves more like rock.

Earlier, scientists had waited for New Horizons to “phone home,” showing the craft had survived its passage through the Pluto system. The “call” came from a healthy New Horizons at 8:52 p.m. EDT on Tuesday evening (00:52 UTC Wednesday).

The Pluto story began early in the 20th century when young Clyde Tombaugh was tasked to look for Planet X, theorized to exist beyond the orbit of Neptune. He discovered a faint point of light that we now see as a complex and fascinating world.

John Grunsfeld is associate administrator for NASA’s Science Mission Directorate in Washington. He said:

Pluto was discovered just 85 years ago by a farmer’s son from Kansas, inspired by a visionary from Boston, using a telescope in Flagstaff, Arizona. Today, science takes a great leap observing the Pluto system up close and flying into a new frontier that will help us better understand the origins of the solar system.

New Horizons’ flyby of the dwarf planet and its five known moons is providing an up-close introduction to the solar system’s Kuiper Belt, an outer region populated by icy objects ranging in size from boulders to dwarf planets. Kuiper Belt objects, such as Pluto, preserve evidence about the early formation of the solar system.

New Horizons’ almost 10-year, three-billion-mile journey to closest approach at Pluto took about one minute less than predicted when the craft was launched in January 2006. The spacecraft threaded the needle through a 36-by-57 mile (60 by 90 kilometers) window in space – the equivalent of a commercial airliner arriving no more off target than the width of a tennis ball.

Because New Horizons is the fastest spacecraft ever launched – hurtling through the Pluto system at more than 30,000 mph – a collision with a particle as small as a grain of rice could incapacitate the spacecraft.

Now that it has reestablished contact, it will take 16 months for New Horizons to send its cache of data – 10 years’ worth – back to Earth.

Composite image of Pluto and Charon, released by NASA on Monday.

Composite image of Pluto and Charon, released by NASA on Monday.

View larger. | Best image of Pluto so far - released today (July 14) - from the New Horizons tam.

View larger. | Pluto nearly fills the frame in this image from the Long Range Reconnaissance Imager (LORRI) aboard NASA’s New Horizons spacecraft, taken on July 13, 2015 when the spacecraft was 476,000 miles (768,000 kilometers) from the surface. This is the last and most detailed image sent to Earth before the spacecraft’s closest approach to Pluto on July 14. The color image has been combined with lower-resolution color information from the Ralph instrument that was acquired earlier on July 13. This view is dominated by the large, bright feature informally named the “heart,” which measures approximately 1,000 miles (1,600 kilometers) across. The heart borders darker equatorial terrains, and the mottled terrain to its east (right) are complex. However, even at this resolution, much of the heart’s interior appears remarkably featureless—possibly a sign of ongoing geologic processes.
Credits: NASA/APL/SwRI

Best image of Pluto from Hubble Space Telescope (l) in contrast to best image of Pluto so far from New Horizons.

Best image of Pluto from Hubble Space Telescope (l) in contrast to best image of Pluto so far from New Horizons.

The NASA New Horizons Pluto Flyby team view the last image before the flyby of Pluto. Photo credit: NASA

The NASA New Horizons Pluto Flyby team view the last image before the flyby of Pluto. Photo credit: NASA

[July 13] In a late-day announcement on Monday, astronomer Alan Stern – who is New Horizons principal investigator – said measurements by New Horizons in the past few days have now confirmed that Pluto is the biggest object in the Kuiper Belt beyond planet Neptune. Pluto measures 1,473 miles (2,370 km) in diameter. Other comparably sized bodies Kuiper Belt bodies – for example, Haumea, Makemake and Eris – had at various times been contenders for the biggest Kuiper belt object title, but now … Pluto wins!

Until we get new images, here are the best images and a sampling of information from New Horizons’ past two weeks, as it made its final approach to the Pluto system.

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A portrait from the final approach. 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. Credits: NASA-JHUAPL-SWRI

Portrait of Pluto (r) and its large moon Charon from the final approach. Composite image from July 11. Image via NASA-JHUAPL-SWRI

Pluto’s bright, mysterious “heart” is rotating into view, ready for its close-up on close approach, in this image taken by New Horizons on July 12 from a distance of 1.6 million miles (2.5 million kilometers). It is the target of the highest-resolution images that will be taken during the spacecraft’s closest approach to Pluto on July 14. The intriguing “bulls-eye” feature at right is rotating out of view, and will not be seen in greater detail. Image credit: NASA/JHUAPL/SWRI

Pluto’s bright, mysterious “heart” is rotating into view, ready for its close-up on close approach, in this image taken by New Horizons on July 12 from a distance of 1.6 million miles (2.5 million kilometers). It is the target of the highest-resolution images that will be taken during the spacecraft’s closest approach to Pluto on July 14. The intriguing “bulls-eye” feature at right is rotating out of view, and will not be seen in greater detail. Image credit: NASA/JHUAPL/SWRI

On July 11, 2015, New Horizons captured a world that is growing more fascinating by the day. For the first time on Pluto, this view reveals linear features that may be cliffs, as well as a circular feature that could be an impact crater. Rotating into view is the bright heart-shaped feature that will be seen in more detail during New Horizons’ closest approach on July 14. The annotated version includes a diagram indicating Pluto’s north pole, equator, and central meridian. Image credit: NASA/JHUAPL/SWRI

On July 11, 2015, New Horizons captured a world that is growing more fascinating by the day. For the first time on Pluto, this view reveals linear features that may be cliffs, as well as a circular feature that could be an impact crater. Rotating into view is the bright heart-shaped feature that will be seen in more detail during New Horizons’ closest approach on July 14. The annotated version includes a diagram indicating Pluto’s north pole, equator, and central meridian. Image credit: NASA/JHUAPL/SWRI

Science team members react to the latest image of Pluto at the Johns Hopkins University Applied Physics Lab on July 10, 2015. Image credit: Michael Soluri

Science team members react to the latest image of Pluto at the Johns Hopkins University Applied Physics Lab on July 10, 2015. Left to right: Cathy Olkin, Jason Cook, Alan Stern, Will Grundy, Casey Lisse, and Carly Howett. Image credit: Michael Soluri

View larger. | On July 11, 2015, New Horizons captured a world that is growing more fascinating by the day. For the first time on Pluto, this view reveals linear features that may be cliffs, as well as a circular feature that could be an impact crater. Rotating into view is the bright heart-shaped feature that will be seen in more detail during New Horizons’ closest approach on July 14. The annotated version includes a diagram indicating Pluto’s north pole, equator, and central meridian.  Image via NASA/JHUAPL/SWRI

View larger. | New Horizons image from July 11. For the first time on Pluto, this view reveals linear features that may be cliffs, as well as a circular feature that could be an impact crater. Rotating into view is the bright heart-shaped feature that will be seen in more detail during New Horizons’ closest approach on July 14. The annotated version includes a diagram indicating Pluto’s north pole, equator, and central meridian. Image via NASA/JHUAPL/SWRI

View larger. | The last best look at Pluto's farside, captured by the New Horizons spacecraft on July 11, 2015, from a distance of 2.5 million miles (4 million kilometers). Photo via NASA/JHUAPL/SWRI

View larger. | The last best look at Pluto’s farside, captured by the New Horizons spacecraft on July 11, 2015, from a distance of 2.5 million miles (4 million kilometers).

A Google Earth overlay of New Horizons’ latest map of Pluto.

Image credit: NASA

New Horizon’s 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. Image credit: NASA/JHUAPL/SWRI

Image credit: NASA/JHUAPL/SWRI

This color version of the July 3 LORRI image was created by adding color data from the Ralph instrument gathered earlier in the mission.Image credit: NASA/JHUAPL/SWRI

Image credit: NASA

Image credit: NASA

New Horizons normal operations resumed July 7 after July 4 anomaly

[July 6] The New Horizons spacecraft experienced an anomaly the afternoon of July 4 that led to a loss of communication with Earth. Communication has since been reestablished and the spacecraft is healthy. Preparations are ongoing to resume the originally planned science operations on July 7 and to conduct the entire close flyby sequence as planned on July 14.

The mission operations center at the Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, lost contact with the unmanned spacecraft at 1:54 p.m. EDT, and regained communications with New Horizons at 3:15 p.m. EDT, through NASA’s Deep Space Network.

During that time the autonomous autopilot on board the spacecraft recognized a problem and – as it’s programmed to do in such a situation – switched from the main to the backup computer. The autopilot placed the spacecraft in “safe mode,” and commanded the backup computer to reinitiate communication with Earth. New Horizons then began to transmit telemetry to help engineers diagnose the problem.

An investigation into the anomaly has concluded that no hardware or software fault occurred on the spacecraft. The underlying cause of the incident was a hard-to-detect timing flaw in the spacecraft command sequence that occurred during an operation to prepare for the close flyby. No similar operations are planned for the remainder of the Pluto encounter.

The mission science team and principal investigator have concluded that the science observations lost during the anomaly recovery do not affect any primary objectives of the mission, with a minimal effect on lesser objectives.

New Horizons Principal Investigator Alan Stern said:

In terms of science, it won’t change an A-plus even into an A.

Adding to the challenge of recovery is the spacecraft’s extreme distance from Earth. New Horizons is almost 3 billion miles away, where radio signals, even traveling at light speed, need 4.5 hours to reach home. Two-way communication between the spacecraft and its operators requires a nine-hour round trip.

Time-lapse movie of Pluto and Charon

Image credit: NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute

Image credit: NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute

These images show the difference between two sets of 48 combined 10-second exposures with New Horizons' Long Range Reconnaissance Imager (LORRI) camera, taken at 8:40 UTC and 10:25 UTC on June 26, 2015, from a range of 21.5 million kilometers (approximately 13 million miles) to Pluto. The known small moons, Nix, Hydra, Kerberos and Styx, are visible as adjacent bright and dark pairs of dots, due to their motion in the 105 minutes between the two image sets. Image credit: NASA/JHU-APL/SwRI

These images show the difference between two sets of 48 combined 10-second exposures with New Horizons’ Long Range Reconnaissance Imager (LORRI) camera, taken at 8:40 UTC and 10:25 UTC on June 26, 2015, from a range of 21.5 million kilometers (approximately 13 million miles) to Pluto. The known small moons, Nix, Hydra, Kerberos and Styx, are visible as adjacent bright and dark pairs of dots, due to their motion in the 105 minutes between the two image sets. Image credit: NASA/JHU-APL/SwRI

Bottom line: The New Horizons spacecraft’s flyby of the Pluto system is on July 14, 2015. Newest images and updates.

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