Asteroids are small, rocky bodies that have been left over from the formation of the planets 4.5 billion…
Earth is a moving target in a shooting gallery. Almost every day, a small chunk of space rock…
Every day about 50 tonnes of rocky material from space lands on the Earth’s surface. These rocks are…
In March 1986, ESA’s Giotto spacecraft flew to within 600 km of comet Halley’s nucleus. It sent back…
Most asteroids are so small and so far away that we can only see them as tiny points…
Even with the largest telescopes it is very hard to see much detail on Mars. In the late…
The Cassini-Huygens mission, involving ESA, NASA and the Italian Space Agency, has changed many of our ideas about…
The Moon has been circling the Earth for more than four billion years. But where did it come…
Everyone on Earth is a traveller through space. First, the Earth zooms around the Sun at a speed…
Pictures sent back by spacecraft such as ESA’s Mars Express show that Mars has many large impact craters.…
Studies of fossils in ancient rocks tell us that life probably began about 4 billion years ago, when…
The Moon is too small to hold onto any air. Without any winds, the sunny side is hotter…
Millions of years ago, the Moon was much closer and bigger in the sky. It was also spinning…
In 1877, the American astronomer Asaph Hall discovered two small moons circling the planet Mars. They were named…
Earth is like no other planet that we have yet observed. It is the only world we know…
Saturn has 31 known moons – more than any other planet except Jupiter. One of them, Titan, is…
Saturn is famous as the ‘lord of the rings’, even though the other three giant gas planets –…
Saturn is the sixth planet from the Sun. It was thought to be the furthest of the planets…
Mars is often called the ‘Red Planet’ because it appears in the sky as an orange-red star. The…
Earth is the largest of the four rocky planets in our Solar System. It is very heavy for…
Titan is larger than the planet Mercury. It is also the second largest moon in the Solar System,…
In many ways, Mars is the most Earthlike of all the planets. A visitor would find that a…
Most stars take millions of years to die. When a star like the Sun has burned all of…
The Sun is a star. Like most stars, the Sun is a ball of very hot gas that…
We live in one of the arms of a large spiral galaxy called the Milky Way. The Sun…
Like people, stars are born, they grow old and they die. Their birth places are huge, cold clouds…
Most astronomers believe the Universe began in a Big Bang about 14 billion years ago. At that time,…
In space, no one can hear you scream. This is because there is no air in space –…
We cannot see anything that happened during the first 300 000 years of the Universe. Scientists try to…
Today, scientists are not so sure that life began on or near the Earth’s surface. Everywhere we look,…
