What Makes the New Horizons' Encounter With Pluto So Extraordinary?

The New Horizons mission to Pluto provides the most detailed view of the dwarf planet that humans have ever seen. How have scientists reached the outer limits of our Solar System, and what do we expect to learn? Find out how to get news from the spacecraft and follow its upcoming close encounter with Pluto.

Sabrina Stierwalt, PhD
6-minute read
Episode #154

Knowledge of Pluto can help our search for extraterrestrial life.

Although Pluto and Charon orbit each other, locked in their shared place in the universe for billions of years, they are actually very different. For starters, Pluto has an atmosphere while Charon does not. Pluto’s interior is believed to be mostly rock while Charon is made up of a combination of rock and water ice.

 nasa.govAlready images from New Horizons, which offer the most detailed view of Pluto to date, have revealed four unusual dark spots on the side of Pluto that faces Charon. These 300-mile-long spots appear connected to a dark band at the equator of the dwarf planet and are surprisingly evenly spaced. They could be plateaus, plains, or other brightness variations on the surface.

Scientists are also looking for evidence of impact craters to see how hard it is for dwarf planets to survive in the outer solar system. Subtle color variations already seen on the surface of Charon by New Horizons appear to be potential craters. Such impacts can also help scientists learn what composes astronomical bodies by dredging up material from below the surface.

The gained understanding of Pluto, Charon, and other bodies in the outskirts of our solar system will help to answer questions about how our solar system formed, how ice dwarf planets like Pluto evolve, and whether or not we expect other solar systems to be the same.

We will be receiving breaking Pluto news for months to come.

Only 1% of the data collected during the flyby will be sent immediately to the Earthlings anxiously awaiting its arrival. The spacecraft can’t take new data while sending existing data back home, and scientists don’t want to waste precious time during the close encounter with Pluto and Charon.

There will be a nail-biting 24 hours from Monday to Tuesday night when NASA scientists and engineers will have no contact with New Horizons while the spacecraft concentrates on collecting data. After communications (hopefully) resume on Tuesday night, the first, highest priority images will be returned—the closest look of Pluto and its moons that anyone has ever seen. Two additional downlinks with other first look photos will occur on July 15-16th and again on July 17th-20th.

The spacecraft will then wait two months before sending the remainder of the data taken during the flyby and afterward. The entire dataset will take 10 weeks to fully download. NASA’s methods for managing the large datasets produced by New Horizons are a great example of how astronomers often lead the way in advancing technology and in finding solutions to technological challenges that are later translated into more everyday applications.

If you want more information on what New Horizons data will be downloaded when, the Planetary Society has a detailed downlink schedule on their website.

You can follow New Horizons as it passes by Pluto on Tuesday, July 14, 2015.

You can follow the spacecraft’s progress via the official NASA Twitter feed @NASANewHorizons and via the Twitter account run by the Principle Investigator for the mission Alan Stern @NewHorizons2015. Although it may be hard for some of us to imagine a world without Twitter, the social media site did not even exist when New Horizons began its journey to the outer reaches of our solar system.

You can also check out NASA TV for interviews and videos, and stay updated through the New Horizons facebook page.

Until next time, this is Sabrina Stierwalt with Everyday Einstein’s Quick and Dirty Tips for helping you make sense of science. You can become a fan of Everyday Einstein on Facebook or follow me on Twitter, where I’m @QDTeinstein. If you have a question that you’d like to see on a future episode, send me an email at everydayeinstein@quickanddirtytips.com.

Images courtesy of nasa.gov.


About the Author

Sabrina Stierwalt, PhD

Dr Sabrina Stierwalt earned a Ph.D. in Astronomy & Astrophysics from Cornell University and is now a Professor of Physics at Occidental College.