Pluto has another moon!

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs." --San Antonio Express-News

Pluto has another moon!

This makes six, with the most recent discovery, named Plutino 15810, an especially unusual one. From the paper’s [pdf] conclusion, published on the Cornell University Library astro-ph website:

Pluto’s system continues being a source of controversy, unanswered questions and surprises more than 80 years after its discovery. Pluto’s planethood demotion in August 2006 still stirs debate today and the recent finding of a fifth moon orbiting Pluto by the [Hubble Space Telescope] just confirms the unexpectedly complex nature of the system. In our work, we show that 15810 currently follows a quasi-satellite orbit relative to Pluto; therefore and besides having 5 regular satellites, Pluto has at least one quasi-satellite. This makes 15810 the first minor body found moving in a 1:1 mean motion resonance with Pluto and the first quasi-satellite found in the trans-Neptunian region of the solar system. It also makes Pluto the second dwarf planet, besides Ceres, to host a quasi-satellite. Our finding also confirms that the quasi-satellite resonant phase is not restricted to small bodies orbiting major planets but it is possible for dwarf planets/asteroids too. We also provide a new and somewhat unexpected mechanism to land minor bodies into the quasi-satellite dynamical state. On the other hand, Plutino 15810 is a natural candidate for a spacecraft rendezvous mission in the framework of NASA’s Pluto-Kuiper Belt Mission New Horizons that is going to complete a flyby with Pluto in 2015 and then continue to explore one or more nearby trans-Neptunian objects in the time frame 2016-2020.

The orbit is actually temporary. Plutino will no longer be a satellite of Pluto in about 350,000 years.


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