New Moons of Pluto

Using NASA’s Hubble Space Telescope to probe the ninth planet in our solar system, astronomers have discovered that Pluto may have not one, but three moons.

Pluto was discovered in 1930. The planet resides 3 billion miles from the sun in the heart of the Kuiper Belt, a vast region of icy, rocky bodies beyond Neptune’s orbit. In 1978, astronomers discovered Charon, Pluto’s only confirmed moon.

“If, as our new Hubble images indicate, Pluto has not one, but two or three moons, it will become the first body in the Kuiper Belt known to have more than one satellite,” said Hal Weaver of the Johns Hopkins Applied Physics Laboratory, Laurel, Md. He is co-leader of the team that made the discovery.

The candidate moons, provisionally designated S/2005 P1 and S/2005 P2, are approximately 27,000 miles (44,000 kilometers) away from Pluto–in other words, two to three times as far from Pluto as Charon.

These are tiny moons. Their estimated diameters lie between 40 and 125 miles (64 and 200 kilometers). Charon, for comparison, is about 730 miles (1170 km) wide, while Pluto itself has a diameter of about 1410 miles (2270 km).

The team plans to make follow-up Hubble observations in February to confirm that the newly discovered objects are truly Pluto’s moons. Only after confirmation will the International Astronomical Union consider permanent (and catchier) names for S/2005 P1 and S/2005 P2.

The Hubble telescope’s Advanced Camera for Surveys observed the two new candidate moons on May 15, 2005. “The new satellite candidates are roughly 5,000 times fainter than Pluto, but they really stood out in these Hubble images,” said Max Mutchler of the Space Telescope Science Institute and the first team member to identify the satellites.

Three days later, Hubble looked at Pluto again. The two objects were still there and appeared to be moving in orbit around Pluto.

“A re-examination of [older] Hubble images taken on June 14, 2002 has essentially confirmed the presence of both P1 and P2 near the predicted locations based on the 2005 Hubble observations,” said Marc Buie of Lowell Observatory, Flagstaff, Ariz., another member of the research team.

The team looked long and hard for other potential moons around Pluto, but they didn’t find any.

“These Hubble images represent the most sensitive search yet for objects around Pluto,” said team member Andrew Steffl of the Southwest Research Institute, “and it is unlikely that there are any other moons larger than about 10 miles across in the Pluto system,” he concludes.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. The Space Telescope Science Institute in Baltimore conducts Hubble science operations. The Institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc., Washington, under contract with Goddard.


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1 thought on “New Moons of Pluto”

  1. As much that has been speculated about
    electro-magnetic/gravitational energies that we could
    use on earth & in space to propel ourselves around, no
    usable system has been proposed….YET…until now!
    We could have massive, slow-moving craft in our
    atmosphere and in space (rockets are deadly), if we
    learn how to trick our inner solar system’s forces
    [“impulse power”], and use them for ALL of mankind’s
    benefit—-[So what if it takes us 3+ weeks to get to
    the Moon, instead of rocketing there in 3 1/2 days; so
    what??….This isn’t a crazy-car, rocket-assisted drag
    race!! We would have to overrule the
    Industrial/Military Complex, of course, because they
    would lose control of us; and they hate change that
    they don’t dictate!]
    {One extra benefit—> Massive earth craft could scoop
    up enough lake or sea-water to put out a forest fire
    in minutes; and, earth transportation vehicles—>
    instead of polluting internal-combustion equipment
    that is poisoning our environment & strip-mining the
    earth, and raising temps everywhere that spawn
    Developing a weak E-M/G force aboard the craft (we can
    do this now)….AND then —>broadcast it like a radio
    signal (digitally), making the earth think the craft
    is just as large as it it, which is like reversing
    magnets….the earth pushes back!
    [A small radio station of 50,000 to 100,000 watts has
    an enormous “footprint”, and by broadcasting a “force”
    signal, the earth pushes us away….or pulls us….
    and like Tarzan, we “swing” from Moon to Mars/Asteroid
    Belt on “vines” of E-M/G forces!]
    All sorts of earthcraft & spacecraft are possible,
    traveling around our inner solar system, utilizing the
    Moon/Mars/Asteroid Belt’s resources for the benefit of
    ALL mankind, EQUALLY! [AND, there is plenty there for
    There is no reason NOW that there be any poor or
    homeless on this planet….many would be in the ‘space
    business’ (many going into space to live, or on
    another celestial body), and there is plenty of wealth
    for EVERYONE, if we have equality among humans….no
    greed & no oligarchs/dictators, as we have now
    planet-wide….especially in the USA!! (See—>”A
    homeless solution: IF people care”, and “The
    Declaration of RE-Independence” on or )
    It’s time for a new chapter in humanity’s history
    where we get it right this time!!!
    My best to all!
    Jim Sorrell

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