Category Astronomy

The spacecraft Rosetta and its lander Philae travelled for ten years across the Solar System to reach the comet 67P/Churtyumov-Gerasimenko. To get enough speed, the spacecraft had to loop around the Earth three times and Mars once, using the gravity of the planets to slingshot through space. On the way they passed lots of other fascinating objects. Finally, in 2014, Philae made the first ever successful touchdown on a comet.

Rosetta was set to be launched on 12 January 2003 to rendezvous with the comet 46P/Wirtanen in 2011. This plan was abandoned after the failure of an Ariane 5 ECA carrier rocket during Hot Bird 7’s launch on 11 December 2002, grounding it until the cause of the failure could be determined. In May 2003, a new plan was formed to target the comet 67P/Churyumov–Gerasimenko, with a revised launch date of 26 February 2004 and comet rendezvous in 2014. The larger mass and the resulting increased impact velocity made modification of the landing gear necessary.

After two scrubbed launch attempts, Rosetta was launched on 2 March 2004 at 07:17 UTC from the Guiana Space Centre in French Guiana, using Ariane 5 G+ carrier rocket. Aside from the changes made to launch time and target, the mission profile remained almost identical. Both co-discoverers of the comet, Klim Churyumov and Svetlana Gerasimenko, were present at the spaceport during the launch

Giant comet

The comet that Rosetta and Philae visited is 4.1 km (2.5 miles) long. That’s roughly the same height as 10 Empire State Buildings stacked up!

 

Picture Credit : Google

Our Solar System isn’t just made up of planets, dwarf planets, and moons. There are lots of other objects that make up the Solar System family. Comets and asteroids have existed since the Solar System formed, and both have hit Earth in the past. There are also smaller bits of rock and dust, called meteoroids, meteors and meteorites.

Asteroid

An asteroid is a rocky object that orbits the Sun. they are much smaller than planets. Some are less than 1 km (0.6 miles) wide.

Meteoroid

A small piece of rock or space dust that has broken off an asteroid or comet is called a meteoroid.

Meteor

A meteoroid that burns up as it passes through the Earth’s atmosphere is called a meteor. They are also known as “shooting stars”.

Meteorite

If the meteor makes it to the ground it is called a meteorite.

Comets

Made from rock, ice and dust, comets are the size of mountains. There are thousands of billions of comets in our Solar System.

Orbiting the Sun

Comets travel around the Sun in an oval-shaped orbit. Some comets are so far away they take tens of millions of years to orbit the Sun. comets get tails when they pass near the Sun and are heated up. The tails always point away from the Sun.

Death of the dinosaurs

 Every day around 90 tonnes (100 tons) of rock and dust from space smashes into the Earth. Most of it burns up in the atmosphere, but larger objects can reach the ground. Scientists think a meteorite about 10 km (6 miles) wide hit into the Earth about 65 million years ago, wiping out the dinosaurs.

 

Picture Credit : Google

Pluto was once thought to be a barren, boring lump of rock at the edge of the Solar System. However, a recent mission has shed new light on this mysterious world. It is filled with ice mountains and volcanoes, and it has particles in its atmosphere that scatter sunlight, giving it a blue sky just like on Earth.

Strange surface

In 2015, photos revealed Pluto’s surface for the first time. NASA scientists spotted smooth plains riddled with craters and mountains of ice.

Dwarf planets

In 2006, it was decided Pluto wasn’t a planet, but a dwarf planet. Dwarf planets are similar to planets in many ways, but share their orbits around the Sun with other objects, such as asteroids and comets. There are currently five recognized dwarf planets in the Solar System, but it thought there are many more.

New Horizons

In 2015 the New Horizons probe made a close flyby of Pluto. It was the first time the dwarf planet had been seen in such clear detail, revealing a world far more active than was previously thought.

Charon

When it wasn’t busy snapping shots of Pluto, New Horizons had the chance to photograph Pluto’s biggest moon, Charon.

The Kuiper Belt

The Kuiper Belt is made up of millions of icy and rocky objects that orbit the Sun at the edge of the Solar System. It is also home to dwarf planets. New Horizons will do its first flyby of a Kuiper Belt object in 2019.

 

Picture Credit : Google

Cold and dark, Uranus and Neptune are known as ice giants because they are made of a mix of gas and icy materials. Both worlds have small rings and many moons. They have only been visited by one spacecraft, Voyager 2, and are still waiting to be explored.

Spinning on its side

Uranus is the odd-ball of the Solar Systems, as it orbits the Sun tilted on its side! Scientists think this is because Uranus was struck by an Earth-sized object early in its life, knocking it over.

Stormy planet

Neptune is the wildest planet in the Solar System. Winds tear through Neptune’s clouds at speeds of up to 2,000 kph (1,200 mph). These ferocious winds once blew a huge storm across the planet. It was called the Great Dark Spot and it was the size of the Earth!

Great Dark Spot

This storm was spotted by Voyager 2 when it visited Neptune in 1989. It had disappeared by the next time Neptune was viewed.

 

Picture Credit : Google

Saturn is the second largest planet, after Jupiter, and is known as the “Jewel of the Solar System” because of its spectacular rings. It is a gas giant that spins so fast it bulges out in the middle.

Bathtime

Despite its mammoth size, Saturn isn’t very dense. This means that if you could build a gigantic bath, Saturn would float in it!

Lord of rings

Saturn is surrounded by rings that are made up of billions of chunks of rock and ice. The rings can be seen from Earth through a telescope.

Saturn has 53 known moons with an additional 29 moons awaiting confirmation of their discovery—that is a total of 82 moons. Saturn cannot support life as we know it, but some of Saturn’s moons have conditions that might support life. About two tons of Saturn’s mass came from Earth—the Cassini spacecraft was intentionally vaporized in Saturn’s atmosphere in 2017.

 

Picture Credit : Google

Jupiter’s four largest moons were the first moons to be discovered orbiting another planet. They are incredible worlds of volcanoes, craters and hidden oceans that have barely been explored. Some could be home to alien life!

Io

Io is similar in size to the Earth’s moon. Chemicals from volcanic eruptions have turned its surface yellow-orange. Io is the most volcanically active world in our Solar System. Hundreds of volcanoes spew lava thousands of metres into the air.

Europa

Europa is the smallest of Jupiter’s four largest moons. On the surface there is water ice and underneath scientists believe there is an ocean! Gigantic jets of water are thought to spout from geysers on Europa’s icy surface. These fountains may be up to 20 times higher than Mount Everest!

Ganymede

The largest moon in our Solar System, Ganymede is even bigger than the planet Mercury! It is made of rock and ice.

Callisto

This battered moon has more craters than any other object in the whole Solar System!

In the night sky

If you look at Jupiter through a telescope you might see bright lights hovering next to the planet. These are actually its four largest moons!

Jupiter’s four largest moons are known as the Galilean moons, after the Italian scientist Galileo Galilei, who discovered them in 1610.

In orbit

With at least 67 moons, Jupiter is almost like its own mini Solar System. Io is the closest of the four largest moons and takes 42 hours to orbit around the planet. Callisto, the furthest away, takes around seventeen days to complete its orbit.

 

Picture Credit : Google