NEW HORIZONS

La nave espacial estadounidense New Horizons ha proporcionado las imágenes más nítidas y cercanas a Plutón cuando queda una semana de su histórica aproximación al desconocido planeta enano.

Las fotografías, captadas el 1 y el 3 de julio, son un aperitivo de lo que podrá verse cuando la sonda haga historia el 14 de julio, al situarse a 12.500 kilómetros de Plutón, lo más cerca que se ha estado nunca de él.

En enero de 2006, cuando New Horizons emprendió esta travesía de nueve años, la NASA subrayaba que Plutón era el único de los nueve planetas del Sistema Solar al que no había llegado nunca una nave espacial.

Pocos meses después, en agosto, Plutón fue relegado a la categoría de planeta enano por la Unión Astronómica Internacional

Entonces la sonda de la Agencia Espacial Estadounidense (NASA), de 480 kilos, ya estaba en camino para desvelar los misterios del desconocido planeta.

Gracias a esta misión hoy se conoce Plutón mejor que nunca, y la comunidad científica tiene grandes expectativas sobre las fotografías de los próximos días, las más precisas de la historia del planeta enano.

El pasado 4 de julio la sonda dio un pequeño susto a los responsables de la misión, cuando se perdió su señal durante algo más de una hora en el centro de control del Laboratorio de Física Aplicada de la Universidad Johns Hopkins, en Maryland (EE.UU.), un incidente que se debió a un problema menor.

Está previsto que New Horizons alcance su máxima aproximación a Plutón a las 07.50 hora del este en Estados Unidos (11.50 GMT) del 14 de julio, nueve años y medio después de dejar la Tierra.

La nave comenzó esta fabulosa travesía el 19 de enero de 2006 en un cohete Atlas V desde Cabo Cañaveral (Florida, EE.UU.). A bordo lleva las cenizas de Clyde Tomabugh, el astrofísico que en 1930 descubrió el punto de luz que hoy llamamos Plutón.

Countdown to discovery! Not since Voyager 2’s flyby of Neptune in 1989 have we flung a probe into the frozen outskirts of the Solar System. Speeding along at 30,800 miles per hour New Horizons will pierce the Pluto system like a smartly aimed arrow.

Edging within 7,800 miles of its surface at 7:49 a.m. EDT, the spacecraft’s long-range telescopic camera will resolve features as small as 230 feet (70 meters). Fourteen minutes later, it will zip within 17,930 miles of Charon as well as image Pluto’s four smaller satellites — Hydra, Styx, Nix and Kerberos.

After zooming past, the craft will turn to photograph Pluto eclipsing the Sun as it looks for the faint glow of rings or dust sheets illuminated by backlight. At the same time, sunlight reflecting off Charon will faintly illuminate Pluto’s backside. What could be more romantic than Charonshine?

Six other science instruments will build thermal maps of the Pluto-Charon pair, measure the composition of the surface and atmosphere and observe Pluto’s interaction with the solar wind. All of this will happen autopilot. It has to. There’s just no time to send a change instructions because of the nearly 9-hour lag in round-trip communications between Earth and probe.

Want to go along for the ride? Download and install NASA’s interactive app Eyes on Pluto and then click the launch button on the website. You’ll be shown several options including a live view and preview. Click preview and sit back to watch the next few days of the mission unfold before your eyes.

Like me, you’ve probably wondered how daylight on Pluto compares to that on Earth. From 3 billion miles away, the Sun’s too small to see as a disk with the naked eye but still wildly bright. With NASA’s Pluto Time, select your city on an interactive map and get the time of day when the two are equal. For my city, daylight on Pluto equals the gentle light of early evening twilight six minutes after sunset. An ideal time for walking, but step lightly. In Pluto’s gentle gravity, you only weigh 1/15 as much as on Earth.

New Horizons is the first mission to the Kuiper Belt, a gigantic zone of icy bodies and mysterious small objects orbiting beyond Neptune. This region also is known as the “third” zone of our solar system, beyond the inner rocky planets and outer gas giants. Pluto is its most famous member, though not necessarily the largest. Eris, first observed in 2003, is nearly identical in size. It’s estimated there are hundreds of thousands of icy asteroids larger than 61 miles (100 km) across along with a trillion comets in the Belt, which begins at 30 a.u. (30 times Earth’s distance from the Sun) and reaches to 55 a.u.

Below you’ll find a schedule of events in Eastern Time. (Subtract one hour for Central, 2 hours for Mountain and 3 hours for Pacific). Keep in mind the probe will be busy shooting photos and gathering data during the flyby, so we’ll have to wait until Wednesday July 15 to see the the detailed close ups of Pluto and its moons. Even then, New Horizons’ recorders will be so jammed with data and images, it’ll take months to beam it all back to Earth.

We’ll be reporting on results and sharing photos from the flyby here at Universe Today, but you’ll also want to check out NASA’s live coverage on NASA TV, its website and social media.

Monday, July 13

10:30 a.m. to noon – Media briefing on mission status and what to expect broadcast live on NASA TV

Tuesday, July 14

7:30 to 8 a.m. – Arrival at Pluto! Countdown program on NASA TV

At approximately 7:49 a.m., New Horizons is scheduled to be as close as the spacecraft will get to Pluto, approximately 7,800 miles (12,500 km) above the surface, after a journey of more than 9 years and 3 billion miles. For much of the day, New Horizons will be out of communication with mission control as it gathers data about Pluto and its moons.

The moment of closest approach will be marked during a live NASA TV broadcast that includes a countdown and discussion of what’s expected next as New Horizons makes its way past Pluto and potentially dangerous debris.

8 to 9 a.m. – Media briefing, image release on NASA TV

Wednesday, July 15

3 to 4 p.m. – Media Briefing: Seeing Pluto in a New Light; live on NASA TV and release of close-up images of Pluto’s surface and moons, along with initial science team reactions.