pluto's close encounter (june 2015)

Pluto’s Close EncounterMeredith L. Rawls, PhD Candidate Department of Astronomy New Mexico State University @merrdiff

Artist’s Impression of the New Horizons Spacecraft approaching Pluto

June 25, 2015

Discovery timeline• Neptune - 1846

• Pluto - 1930

• Charon - 1978

• Nix, Hydra - 2005

• Kerberos - 2011

• Styx - 2012

!

Clyde Tombaugh’s legacy• Took photographic plates at Lowell Observatory in

1930 and “blinked” them to search for Planet X

• Moved to Las Cruces in the 1940s, helped form the NMSU Astronomy Dept in the 1970s

Can you discover Pluto?!

!

Jan 23, 1930

Can you discover Pluto?!

!

Jan 29, 1930

A chance discovery• Supposed perturbations in Uranus’ and Neptune’s

orbit predicted the existence of “Planet X”

• Models suggested a 6-Earth mass planet at 43 AU

• Found Pluto instead (0.002-Earth mass, 30–50 AU)

VenetiaBurneyPhairPercival Lowell

ElizabethLangdonWilliams

“Best Image” of Pluto

How big? How far?

How big? How far?

!How big? How far?

How big? How far?

How big? How far?

Image from 2006, when only three moons were known

Pluto facts

Family Portrait

New HorizonsLaunch: January 19, 2006

• Apollo to Moon = 3 days • New Horizons to Moon =

9 hours • Could travel from NY to

LA in 4 minutes

• Speed set by launch and Jupiter slingshot

• Propulsion is for course corrections, not speed

New Horizons is really fast!

Inst

rum

ents

Communications• It’s hard to get data from Pluto! • Can downlink data OR take photos

• Last navigation data, July 12 • “Fail Safe” downlinks, July 12-13 • “E-Health 1” near-flyby image, July 13 • —24 hours of terror— • “Phone Home” post-flyby beep, July 14 • “First Look” images sent July 15-16 • “High Priority” data sent July 17-20 • No new images until September 14

(busy with other instruments) • Full set of low-quality images, Sep-Nov • All high-quality images, Nov + 1 year

SIMULATIONS

SIMULATIONS

Latest Images

April 2015

Latest Images

May 2015

Latest Images

Latest Images

Latest Images

(this is a GIF; if it doesn’t play, go here: http://www.planetary.org/blogs/emily-lakdawalla/2015/06230439-new-horizons-update.html)

Latest Images

Latest Images

Lower-resolution MVIC color image used to

colorize a higher-resolution June 21 LORRI image of

Pluto and Charon

Today’s Latest Image!

• Celestial body that orbits the Sun

• Massive enough to be spherical

• Has cleared the neighborhood around its orbit

What’s in a name?

Planet

• Celestial body that orbits the Sun

• Massive enough to be spherical

• Has NOT cleared the neighborhood around its orbit

• Is not a satellite (moon)

What’s in a name?

Dwarf Planet

What’s in a name?

Pluto is in good company

Stay tuned!• See all the latest images:

http://pluto.jhuapl.edu/soc/Pluto-Encounter/

• This is probably the only time Pluto will be visited by a spacecraft in our lifetime

• We are just beginning to answer questions about our own Solar System, and all the while discovering new ones!