Wednesday, July 18, 2012

Pluto’s Fifth Moon Has No Name (Yet)

It's hard to believe, but the arrival of NASA's New Horizons spacecraft at Pluto is just three years away. The logistics of the high-speed flyby, already challenging, just got more complicated: Pluto turns out to have a fifth moon.

Although for now its official designation is S/2012 (134340) 1 — "134340" being the minor-planet number assigned to Pluto — the new find has been nicknamed "P5". (Easier to remember, don't you agree?) Its existence was announced last night by the IAU's Central Bureau for Astronomical Telegrams

... It's no coincidence that all these moons orbit in the same plane as Pluto's equator. Most likely they formed from debris tossed out when a renegade object struck Pluto long ago. Collisions in this distant region of the solar system are typically so slow that most of the resulting fragments couldn't have reached escape velocity, which is a bit under 1 mile per second for Pluto. So most of it would have stuck around.

But that doesn't automatically lead to satellite formation. Ballistically speaking, any stuff that lingered should just have just fallen back onto Pluto itself. However, tidal interactions among the most massive chunks could have allowed enough of them to remain in orbit to form Charon and the other moons.

All the moons of Pluto are very small.

Pluto itself is smaller than our Moon.

Pluto itself is smaller than our Moon
but Pluto has five moons and maybe more.

Here on Earth our Moon is often featured
in romantic poetry and love songs.

It must be very romantic out there
with five moons always circling overhead
and the Sun so far away and so dim
that it’s always something like twilight time.

The most romantic thing to do out there
probably would be to point toward the Sun
and then a little way off to the side
and lean up against the person you’re with
and say, “See that bright blue star? That’s the Earth.”

And the five moons of Pluto would circle
around you both as if Pluto itself
were surrounding you and keeping you safe
so that you could lean against each other
and share the romance looking far away.

It must be very romantic out there
by Pluto and the five moons of Pluto
where it’s always something like twilight time
and it’s always so very far away.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

That image comparing the Moon to Pluto
was generated by
Wolfram|Alpha by typing:

compare diameter of the moon to diameter of pluto

I’m not sure which is more amazing to me,
that we know so much about this tiny planet so far away,
or that
Wolfram|Alpha provides this kind
of wonderful resource to everyone on the web.
It’s all too romantic for words. Almost.

Moonlight Becomes You

Pluto In Magic And Alchemy

The New Horizons Spacecraft As Julia Adams

A Spaceship That Sparks

How Pluto’s First Moon Got Its Name

No comments: