--- title: Pluto, the Kuiper belt, the Oort cloud and comets — a lesson of Mova's school · trees and pragmatics description: «Pluto, the Kuiper belt, the Oort cloud and comets», a lesson of the space course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: Beyond Neptune lies the Kuiper belt, a huge ring of icy bodies, and Pluto is one of the biggest of them, which is why it w --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Space](https://md.mova.elamur.ai/free/en/corpora/school/space/) / Pluto, the Kuiper belt, the Oort cloud… # Pluto, the Kuiper belt, the Oort cloud and comets Lesson 15 of the space course of Mova's primary school: 16 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/0/) — Beyond Neptune lies the Kuiper belt, a huge ring of icy bodies, and Pluto is one of the biggest of them, which is why it was called a dwarf planet in 2006: it shares its path with many similar objects. - [1](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/1/) — When New Horizons flew past in 2015, Pluto turned out to be a lively world with a heart-shaped plain of nitrogen ice, mountains of water ice and a thin blue haze. - [2](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/2/) — Much further out, scientists think a vast shell of icy bodies, the Oort cloud, surrounds the whole Solar System, perhaps a quarter of the way to the nearest star. - [3](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/3/) — Now and then one of these icy bodies falls in towards the Sun and becomes a comet: a dirty snowball a few kilometres across that warms up and grows a glowing head and tails, like breath steaming on a cold morning. - [4](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/4/) — Comets leave dust along their path, and when the Earth runs through that dust every year we see a meteor shower, such as the Perseids in August. - [5](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/5/) — Pluto was discovered in 1930 by Clyde Tombaugh, a young American astronomer, by comparing photographs of the sky taken days apart. - [6](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/6/) — In 2006 astronomers reclassified Pluto as a dwarf planet because it has not cleared its orbit of other similar objects. - [8](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/8/) — Pluto's biggest moon Charon is about half Pluto's width, so the two orbit a point between them, almost like a double planet. - [9](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/9/) — The Kuiper belt is a huge ring of icy bodies beyond Neptune, from about 30 to 50 times the Earth's distance from the Sun. - [10](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/10/) — In 2019 New Horizons flew past Arrokoth, a Kuiper belt object shaped like a snowman, the most distant object ever explored up close. - [11](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/11/) — The Oort cloud is a vast shell of icy bodies thought to surround the Solar System, reaching perhaps a quarter of the way to the nearest star; it has never been seen directly, but scientists think it is there because some comets keep falling in from that far away. - [12](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/12/) — Comets are dirty snowballs of ice, dust and rock a few kilometres across, which grow a glowing head and tails, often millions of kilometres long, when they come near the Sun and its heat turns their ice into gas and frees dust. - [13](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/13/) — A comet can have two tails, a curved dust tail and a straight blue gas tail, and both point away from the Sun. - [14](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/14/) — Halley's Comet returns about every 76 years; it last came in 1986 and will next be bright in 2061. - [15](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/15/) — Europe's Rosetta spacecraft orbited Comet 67P from 2014 to 2016 and dropped the lander Philae onto it, the first landing on a comet. - [16](https://md.mova.elamur.ai/free/en/corpora/school/space/15-pluto-the-kuiper-belt-the-oort-cloud-and-comets/16/) — Meteor showers happen when the Earth passes through trails of dust left by comets, such as the Perseids every August. - ← previous: [Uranus and Neptune](https://md.mova.elamur.ai/free/en/corpora/school/space/14-uranus-and-neptune/) - next →: [Meteors, meteorites and shooting stars](https://md.mova.elamur.ai/free/en/corpora/school/space/16-meteors-meteorites-and-shooting-stars/) - ↑ back to [Space](https://md.mova.elamur.ai/free/en/corpora/school/space/)