Comets
24 questions tagged Comets — spanning every one of the seven Ws.
Why do comets grow tails near the Sun?
Solar heat makes comet ices vaporize, and sunlight and the solar wind push the released gas and dust into long tails.
Why do comets grow tails when they approach the Sun?
Solar heat vaporizes ice in the comet, releasing gas and dust. Solar wind and radiation push that material away from the nucleus, forming tails.
When was the first soft landing on a comet made?
The European Space Agency’s Philae lander touched down on comet 67P on 12 November 2014. It was the first landing on a comet nucleus.
When was the first successful landing on a moving comet nucleus followed by a surface mission?
Rosetta’s Philae landing on 12 November 2014 was the first time a lander operated on a comet nucleus. It sent back data before its batteries ran out.
When was the first spacecraft to visit a comet up close?
Giotto flew by Halley’s Comet on 14 March 1986. It was the first spacecraft to return close images of a comet nucleus.
When was the first spacecraft to land on a comet?
In 2014, the Rosetta mission’s Philae lander made the first landing on a comet.
Whose mission first landed on a comet?
ESA’s Rosetta mission, led by Gerhard Schwehm and mission scientist Matt Taylor, deployed the Philae lander on comet 67P in 2014. It was the first controlled landing on a comet’s surface.
Whose calculations first suggested the Solar System was surrounded by a huge cloud of icy bodies?
Jan Oort proposed the Oort Cloud in 1950. His idea explained where long-period comets may come from.
Whose calculations helped predict the return of Halley’s Comet?
Edmond Halley predicted that the comet seen in 1531, 1607 and 1682 was the same object and would return in 1758. The comet returned after his death and now bears his name.
How do comets grow tails near the Sun?
Heat from the Sun makes ice on the comet’s surface turn directly into gas, carrying dust away. The solar wind then shapes the ion tail, which always points away from the Sun.
Why do comets develop tails near the Sun?
Solar heat turns ice into gas, and sunlight plus the solar wind push dust and gas away from the comet’s nucleus to form tails.
What is a comet nucleus?
A comet nucleus is the solid icy core of a comet, made of frozen gases, dust, and rocky material.
When was the first spacecraft to visit a comet launched?
The first spacecraft to fly by a comet was ICE in 1985, but the first dedicated comet encounter mission was Giotto in 1986.
Whose calculations helped predict the return of Halley’s Comet in 1758?
Edmond Halley’s calculations correctly predicted the periodic return of the comet that now bears his name. He identified that the 1531, 1607 and 1682 comets were the same object.
Whose spacecraft first reached the surface of a comet?
The European Space Agency’s Rosetta mission, with the Philae lander, made the first soft landing on a comet in 2014. It landed on Comet 67P/Churyumov–Gerasimenko.
Whose spacecraft first entered orbit around a comet?
The European Space Agency’s Rosetta spacecraft was the first to orbit a comet, arriving at Comet 67P in 2014. It studied the comet for more than two years.
Whose calculations helped prove that comets follow precise orbits and return after long intervals?
That was Edmond Halley. He calculated that the comet seen in 1531, 1607, and 1682 was the same object and predicted its return in 1758.
Whose calculations helped show that comets return in predictable orbits?
Edmond Halley’s. He used Newtonian gravity to predict the return of the comet now named after him.
How do comets develop tails when they get close to the Sun?
Solar heat vaporizes their ices and releases gas and dust, which the solar wind and sunlight push into long tails.
Why do comets develop tails when they get close to the Sun?
Solar heat turns comet ice into gas, releasing dust and vapour that form a tail. The solar wind and sunlight push the material away from the Sun.
When was the first direct measurement of a comet’s nucleus made?
The first close-up study of a comet nucleus came on 14 March 1986, when Giotto flew past Halley’s Comet.
When was the first comet sample return mission completed?
Stardust returned samples from comet Wild 2 to Earth on 15 January 2006.
Whose calculations predicted the return of Halley’s Comet?
Edmond Halley predicted the comet’s return in 1705. He used Newton’s new theory of gravity to show it would come back in 1758.
How do astronomers know a comet’s tail points away from the Sun?
Solar wind and sunlight push dust and ionized gas away from the Sun, regardless of the comet’s direction of travel. That is why a comet’s tail can point away from the Sun even when the comet is moving another way.