NEW HORIZONS CELEBRATES CLYDE TOMBAUGH S BIRTHDAY WITH NEW PLUTO IMAGES LAUREL KORNFELD

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1 NEW HORIZONS CELEBRATES CLYDE TOMBAUGH S BIRTHDAY WITH NEW PLUTO IMAGES LAUREL KORNFELD NASA's New Horizons spacecraft has snapped new images of the dwarf Planet Pluto and its largest moon Charon. NASA s New Horizons team celebrated what would have been dwarf planet Pluto discoverer Clyde Tombaugh s 109th birthday by releasing new photos of Pluto and Charon orbiting each other, taken by the spacecraft for optical navigation purposes on Feb. 4. These images also serve to mark the spacecraft s approach to and flyby of the tiny world and its fleet of moons. The two images were captured by the Long Range Reconnaissance Imager (LORRI ), a panchromatic highmagnification imager on Jan. 25 and 27, at the start of the mission s Approach Phase 1. LORRI consists of a telescope with an 8.2-inch (20.8-centimeter) aperture, focusing visible light onto a charge-couple device. The image of Pluto and its moon Charon, taken by NASA s New Horizons spacecraft, was magnified four times to make the objects more visible. Image Credit: NASA/JHU APL/SwRI The first image was taken at a distance of 126 million miles (203 million km) from Pluto and the second from 1.5 million miles (2.5 million km) closer. These pictures are the first of hundreds LORRI will capture against a background of star fields for navigational purposes.known as OpNavs, the long-distance images will enable NMSU News Clips (1 of 5) University Communications

2 navigators to determine whether any course-correction maneuvers are necessary to keep the spacecraft on a precise journey to and then through the Pluto system. One such maneuver has already been scheduled for Mar. 10. Pluto takes up two pixels while Charon takes up only one pixel in LORRI s field of view. To make both objects more visible, the images taken were magnified four times. With an exposure time of only one-tenth of a second, Pluto s smaller moons are not visible. Two of those moons, Nix and Hydra, will be visible in later images LORRI plans take with exposure times up to 10 seconds. The mission chose to pay tribute to Tombaugh, who was born on Feb. 4, 1906 and discovered Pluto in 1930, by publishing the new images on his birthday. This is our birthday tribute to Professor Tombaugh and the Tombaugh family, in honor of his discovery and life achievements which truly became a harbinger of 21st century planetary astronomy, noted Principal Investigator Alan Stern of the Southwest Research Institute in Boulder, Colorado. The LORRI instrument on the New Horizons spacecraft is a panchromatic high-magnification imager designed to map Pluto s farside and provides high resolution geologic data. Image Credit: NASA/JHUAPL Stern emphasized, These images of Pluto, clearly brighter and closer than those New Horizons took last July from twice as far away, represent the first steps at turning the pinpoint of light Clyde saw in the telescopes at Lowell Observatory 85 years ago, into a planet before the eyes of the world this summer. Pluto as seen by the Hubble Space Telescope. Image Credit: NASA/Hubble NMSU News Clips (2 of 5) University Communications

3 Of course, Dad would be thrilled about the New Horizons mission and about the success to date of that mission, Alden Tombaugh noted. He always wanted to know more about everything that was out there. Tombaugh, who died in Jan only weeks before his 91st birthday, also discovered 15 asteroids, Comet 274P/Tombaugh-Tenagra, hundreds of variable stars, several star clusters, several galaxy clusters, and a galaxy supercluster. When he looked at Pluto, it was just a speck of light. To actually see the planet that he had discovered and find out more about its atmosphere, find out more what it is and actually get to see the moons of Pluto he would have been astounded, daughter Annette Tombaugh-Sitze said. And I m sure to have the planet that you discovered better defined, better understood it would have meant so much to him, she stated. He would be absolutely delighted with the fact that finally, we were getting the ability to determine what the composition of Pluto was, why its orbit is what it is, what other objects act on it, and the objects that surround it in the Kuiper Belt, Alden Tombaugh said. Clyde Tombaugh discovered Pluto in 1930 and a portion of his ashes are aboard the New Horizons spacecraft. Photo Credit: NASA Only 24 when he discovered Pluto at the Lowell Observatory in Flagstaff, Arizona, Tombaugh went on to a distinguished career as a professor at New Mexico State University, where he founded an astronomy department and taught from 1955 until While he did not live to see New Horizons launch, Tombaugh was aware of efforts to send a spacecraft to Pluto. Jet Propulsion Laboratory (JPL) researcher Robert Staehle in 1992 asked Tombaugh for permission to visit Pluto. A portion of Tombaugh s ashes are onboard the spacecraft, in a container on its underside. I told him he was welcome to it though he s got to go on one long, cold trip, Tombaugh told him. For many years, Pluto was thought to be larger than it actually is because observers did not realize they were actually looking at two objects. Charon, Pluto s largest moon, was not discovered until It is half Pluto s size and separated from the planet by a mere 12,160 miles (19,570 km). NMSU News Clips (3 of 5) University Communications

4 A comparison of images of Pluto and its large moon Charon, taken in July 2014 and January Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute The two objects are tidally locked, always presenting the same face toward one another, and orbit a center of gravity outside of Pluto, leading some scientists to consider Pluto-Charon as a double planet system. Animations of New Horizons images show the two objects orbiting each other. Hal Weaver, New Horizons project scientist at the Johns Hopkins University Applied Physics Laboratory (JHUAPL) in Laurel, MD, noted Pluto is finally becoming more than just a pinprick of light. As New Horizons closes in, pictures of Pluto and its large moon Charon will grow larger and clearer, Weaver noted. New Horizons image of the Jovian moon Io. Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute In May, two months before its closest approach to the planet, the spacecraft will begin sending back images with a higher resolution than those taken by the Hubble Space Telescope. Hubble s first, blurry pictures of Pluto were taken in the 1990s. Later Hubble images led to the discovery of four additional Plutonian moons. Nix and Hydra were found in 2005, and two more satellites were discovered after New Horizons launch, Kerberos in 2011 and Styx in The quality of the latest images confirm LORRI is performing just as well as it did when New Horizons launched nine years ago, Weaver said. NMSU News Clips (4 of 5) University Communications

5 Launched in Jan. 2006, New Horizons has already traveled three billion miles over the past nine years. The fastest spacecraft ever launched, it reached Jupiter and imaged the giant planet and its moons in Feb This image depicts New Horizons planned trajectory through the solar system. Image Credit: NASA Now heading to Pluto at a speed of 31,000 miles per hour, New Horizons has seven instruments, including LORRI, which will take measurements of the solar wind, dust, and energetic particles in Pluto s region, study the planet s atmosphere, and map its surface. Pluto s composition is estimated to be 70 percent rock. Its temperature is about 43 Kelvin (-230 degrees C), and it has a thin atmosphere of nitrogen, methane, and carbon monoxide. Hubble images indicate the planet experiences seasonal changes. From spectroscopic analyses, researchers have determined its surface is composed of 98 percent nitrogen ice, along with tiny amounts of methane and carbon monoxide. The small world could harbor a subsurface ocean and possibly even geysers such as those recently discovered on Ceres and on Saturn s moon Enceladus. NMSU News Clips (5 of 5) University Communications