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Monthly Archives: October 2015

Credit: Lunar and Planetary Insitute

Credit: Lunar and Planetary Insitute

Planetary Science Nuggets are PowerPoint slides that have been provided to NASA Science Mission Directorate’s Planetary Science Division by members of the scientific community to highlight important science results or mission activities. A subset of these submissions are selected by the Planetary Science Division to be presented to SMD leadership and, potentially, NASA leadership, OSTP and the White House. This collection represents those selected Nuggets.

Link: Planetary Science Nuggets hosted by the Lunar and Planetary Institute.

From a press release originally published on the John Hopkins Laboratory website on October 15, 2015.

Following the first exploration of the Pluto system in history, NASA’s New Horizons team have published their first research paper detailing their findings of the distant planet.

The paper, entitled “The Pluto System: Initial Results from its Exploration by New Horizons,” describes an unusual heart-shaped region, intriguing moons, and a surprising degree of diversity and complexity in the Pluto System.

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Team members believe that some of the processes on Pluto have occurred relatively recently, including those which involve the water-ice rich crust that they have discovered. This raises fundamental questions about how small planets remain active billions of years after their formation.

NASA’s New Horizons spacecraft made it to within 7,750 miles of Pluto’s surface at its point of closest approach, gathering so much data that scientists won’t see the extent of it for another year.

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Jim Green, director of planetary science at NASA Headquarters in Washington, describes the mission as only the beginning. “The New Horizons mission completes our initial reconnaissance of the solar system, giving humanity our first look at this fascinating world and its system of moons. New Horizons is not only writing the textbook on the Pluto system, it’s serving to inspire current and future generations to keep exploring — to keep searching for what’s beyond the next hill.”

For more information on what we know so far about the dwarf planet right on the fringes of our Solar system, see Chapter 8.1 of The Cosmos.

Link: for the original press release, click here.

To commemorate October as American Archive Month, six new images have been released from the Chandra Data Archive. The archive houses the data from Chandra’s observations, making them available for ongoing and future studies.



The objects are: (top row, l-r) W44, a supernova remnant; SN 1987A, the remnant of a bright nearby supernova; Kes 79, a super nova remnant; (bottom row, l-r) MS 0735.6+7421, an erupting galaxy cluster; 3C295, a galaxy cluster within a superheated gas cloud; the Guitar Nebula, a pulsar.

Further details about these images and objects, and many more, may be found on the Chandra website.

From an article published August 28, 2015 on The New York Times website:

Credit: Alex Parker, via NASA

Credit: Alex Parker, via NASA

Fresh from its Pluto flyby in July 2015, NASA’s New Horizons spacecraft has a new mission. The next destination for the probe is to be a much smaller ice ball in the outer Solar System, almost a billion miles beyond Pluto.

If NASA approves the extension to the mission, the spacecraft will visit the icy body known as 2014 MU69 in 2019 to capture photographs and data, in a similar way as for the examination of Pluto. While the vistas of this object would not be as impressive as those of Pluto, it would provide a close-up look at another piece of debris beyond Neptune, part of what is known as the Kuiper belt (see Section 8.2, pp. 202-204 in The Cosmos).

NASA has already examined smaller icy objects like comets, some of which originate in the Kuiper belt, but the flyby of 2014 MU69 will “connect the dots”, says S. Alan Stern, New Horizons’ principal investigator. As an intermediate-size Kuiper belt object, the gap in our knowledge between smaller icy objects and the far greater Pluto will aim to be filled.

The New Horizons spacecraft is to adjust course through a series of four thruster firings in late October and early November. New Horizons would also make more distant measurements of 20 other Kuiper belt objects en route to 2014 MU69.

For more information on spacecrafts flying by comets, see Section 8.3f, pp. 210-214 in The Cosmos.

Link: Full article here

Credit: Rebekah Dawson, University of California, Berkeley

Credit: Rebekah Dawson, University of California, Berkeley

This new graph plots orbital period versus planetary radius for planetary candidates discovered by the Kepler Space Telescope (see also The Cosmos, Section 9.2d, pp. 240-243, and Figure 9-9, p. 239). The colored symbols represent how many planets orbit a given star, and the legend lists how many of this type of system are in the catalog. (For example, the catalog lists 2967 stars with only one planet orbiting them.) Planets with shorter orbital periods are overrepresented because geometric factors and frequent transits make them easier for Kepler to detect. The upward slope in the lower envelope of these points is caused by the difficulty in detecting small planets with long orbital periods, for which transits are shallow and few are observed.

Link: article in EOS; for more detailed information, see Lissauer, J. J., R. I. Dawson, and S. Tremaine (2014), Advances in exoplanet science from Kepler, Nature, 513, 336–344 (arXiv version available here).

From an article published on September 30, 2015 at


Colorful new maps of Ceres, charted by NASA’s Dawn space probe, have been unveiled at the European Planetary Science Conference in France. The maps highlight the dwarf planet’s topography and composition, as well as a pyramid-shaped mountain and the Occator crater, where many mysterious bright spots can be found.

Dawn scientists are also discussing three bursts of energetic electrons that have them puzzled. As Dawn principal investigator Chris Russell put it, “Ceres continues to amaze”.

To learn more about the outer Solar System, see Chapter 8 of The Cosmos.

Link to the full article on

From an article on the American Scientist website:

Debra Fischer is an astrophysicist at Yale University who has discovered hundreds of exoplanets, and she was the first to discover a system with several exoplanets around one star.

On September 30, American Scientist met up with Dr. Fischer for a Google Hangout to discuss the methods used to find exoplanets, how much we can currently decipher about these planets’ properties, and what new information some planned ground and space-based observatories might be able to contribute. She also tackled the all-important question of whether we might find exoplanets that support life.

This event marked the first in a series of Google Hangouts with all of Sigma Xi’s Distinguished Lecturers, one of whom is Dr. Fischer. Dr. Fischer also helps to run a citizen science project called Planet Hunters, which aims to classify readings and find exoplanets with the public’s help.

For an in-depth discussion on exoplanets and how they are discovered, see Section 9.2, p. 236-244 in The Cosmos.

Link: Original article on American Scientist


The 2015 Nobel Prize in Physics was given on October 6 to Takaaki Kajita of the Superkamiokande experiment and to Arthur McDonald of the Sudbury Neutrino Observatory.  The work at both those sites is thoroughly discussed in The Cosmos (see Section 12.7, p. 322-325) about the solar-neutrino experiment.


By showing definitively that a mix of the three types of neutrinos reaches the Earth, combining the knowledge that only electron-neutrinos leave the Sun shows that neutrinos change in type en route.  Only if neutrinos have mass can such changes take place, so the discovery is a major challenge to the Standard Model of particle physics.

This is the third Nobel Prize for neutrino research.  Half the 1995 Nobel Prize went Fred Reines for the discovery of neutrinos in an atomic-reactor beam (his co-discoverer, Clyde Cowan, having died before the prize was given, making him ineligible).  Half the 2002 Nobel Prize went to Ray Davis, who ran the chlorine version of the neutrino experiment at the Homestake Mine, and Masatoshi Koshiba, who was in charge of Kamiokande (the Neutrino Detection Experiment [NDE] in the Kamioka mine in Japan). John Bahcall from the Institute for Advanced Study, who had done the bulk of the theoretical work involved, was omitted from the prize, unfortunately (again, as the prize is not awarded posthumously).

Links: 2015 Nobel Prize in Physics at the Royal Swedish Academy of Sciences; Dennis Overbye’s analysis for the NY Times (including a discussion of the next investigations via The Deep Underground Neutrino Experiment, DUNE).