a presentation by ann-kathrin rink. introduction facts about pluto a dwarf among giants the...

DISCOVERY OF PLUTO

A presentation by Ann-Kathrin Rink

Plan

introduction facts about pluto a dwarf among giants the discovery sources

Introduction

The solar system 8 planets(pluto is not a planet

anymore)

Kuiper belt objects (KBO‘s)

Region of the solar system beyond neptune‘s orbit → is a bit like the asteroid belt (but much larger) → 30 AU to 55 AU away from the sun

The Kuiper Belt

KBO‘s

→ first KBO was discovered in 1992→ home of at least 2 dwarf planets

Eris & Pluto

Facts about Pluto

3 moons Diameter 2320 km Mass: 0,0021 Earthmass Average distance from sun: ≈ 6

billion km → Maximum: ≈ 7,4 billion km → Minimum: ≈ 4,4 billion km Eccentricity of its orbit 0,25 → Compared with other planets, the

eccentricity is extremely high e.g. Earth : 0,017 ; Neptune: 0,009 Orbital period: 248,6 earth

years Rotation period: 6,4 earth days

A dwarf among giants

Pluto – a dwarf planet

Was stripped of his fully planet status → August 2006 reclassified as a “dwarf planet” Why? → discovery of a number of KBO’s of similar if not greater size

→ if the IAU did not action like that, other KBO’s would have become planets

→ some astronomers question pluto’s status because of its size ↔ more similarities with the KBO’s

The Discovery

The First Try…

1905 Percival Lowell hypothesized the possibility of a planet X

Based on perturbations of Neptune and Uranus → influence of other body’s gravity

Calculated the approximate position → was not able to find it before he died in

1916

1919 W. H. Pickering recalculated the position of the planet X → failed to find Pluto, too

After searching for an long time…

… C. W. Tombaugh finally discovered Pluto on the 18th February in 1930

Used calculation of is predecessors

Fotographes certain sections twice → interval of 6 days

Searching for a “wandering” star

Analysed these pictures with a blink comparator → shows both pictures in series → a ‘wandering’ star will blink

Today we know that Pluto ‘s mass is not big enough to perturb Uranus’ and Neptune’s orbit...

→ In the end Pluto’s discovery must have been a lucky break

Thank you for your attention

Sources:

www.solarspace.co.ukwww.abenteuer-universum.dewww.nasa.comwww.space.comwww.news.bbc.co.ukHarenbergs Schlüsseldaten Astronomie