A Galactic Debut

Calm has been restored to the outer-solar system following a row over what to call a dwarf planet and exactly how it should be characterised.

The red-speckled bright object that hovers near Pluto was initially nicknamed Easterbunny because it was discovered shortly after Easter in 2005.

Galactic unrest erupted in the ranks of the International Astronomical Union over what the official name should be.

And after much debate, the name Makemake has been decided on as a tribute to the Polynesian god of fertility and creator of humanity.

As for its status, the newly-named planet which is coated in red methane is now officially a plutoid.

Pluto, which made headlines last year as it was demoted from its planet status, and Eris are the other two plutoids. A fourth dwarf planet named Ceres has been excluded from the plutoid club because it orbits in the asteroid belt between Mars and Jupiter.

Makemake has a diameter of roughly 1,000 miles and is quite bright given its distance from the Sun.

Despite this, it was not discovered until recently, well after many much fainter objects in its region of the solar system.

Mike Brown of the California Institute of Technology, who discovered the dwarf planet and suggested its name, discussed the trouble he had naming the planet in his blog.

"Three years is a long time to have only a license plate number instead of a name, so for most of the time, we simply referred to this object as 'Easterbunny' in honor of the fact that it was discovered just a few days past Easter in 2005," he writes.

He discusses the trouble the team had finding a name, until they considered the island Rapa Nui, better known as Easter Island, and its mythology.

"I wasn't familiar with the mythology of the island so I had to look it up, and I found Make-make, the chief god, the creator of humanity, and the god of fertility.

"I am partial to fertility gods for things I discovered around that time. Eris, Makemake, and 2003 EL61 were all discovered as my wife was three to six months pregnant with our daughter."

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Incredible pictures of Mars - and they look surprisingly like some parts of Earth

Ever since Victorian astronomers pointed their telescopes towards Mars and wrongly believed they had discovered canals, mankind has been obsessed by the red planet.

Now these astonishing new images - captured by a European spacecraft in orbit around Mars - are helping to fuel that fascination.

They show in astonishing detail a network of giant valleys, vast plains and towering waterfalls carved into the surface of our neighbouring planet, millions of miles away.

And while Mars today appears lifeless and parched, they are a reminder of how its surface was shaped by fast flowing streams, rivers and oceans.

The pictures were captured by the European Space Agency's Mars Express Probe - a spacecraft the size of a large fridge-freezer that has been circling Mars since Christmas 2003.

Mars Express infamously gave Britain's ill-fated Beagle 2 probe a lift to Mars. While that mission ended in disaster, the Mars Express has been a fantastic success.

Over the last five years its stereo, high resolution camera has taken thousands of images of the surface, revealing the planet's awe inspiring beauty in unprecedented detail.

The latest images show the Echus Chasma, a vast valley just north of Mars equator around 62 miles long and six miles wide. The feature is cut into a high plateau and its steep-sided cliffs - some 12,000 feet high - bear a striking resemblance to the canyons of North America.

Thunderous waterfalls may have once plunged over these cliffs, from the high Lunea Planum plateau that surrounds the Echus Chasma, on to the valley floor below.

Some of the images show a five mile wide impact crater formed when asteroids - lumps of floating rock in space - smashed into Mars. Others show a 15 mile long dyke formed when molten rock, evidence of Mars's volcanic past.

At the edges of the main valley lie smaller light-coloured tributary valleys or "sapping canyons" - around six miles long and 1800 feet deep.

The Echus Chasma - described by Nasa as one of the largest water sources on the planet - is connected to a much bigger valley system called the Kasei Valles which extends thousands of miles to the north.

Both valleys are impressive - but are dwarfed by an even larger canyon which lies to the south. The Valles Marineris is four miles deep in places, around 120 miles wide and 2,500 miles long.

The images were created by combining pictures taken from different orbits. The images can be viewed from different angles in three dimensions

Mars Express launched in June 2003. The craft is a cube around 5ft by 6ft by 5ft with two 60ft long radar antennae. It is photographing the entire surface of Mars in high resolution, producing a detailed colour map of the minerals on the surface, mapping the atmosphere and probing beneath the surface using radar.

Interest in Mars is at an all time high. Nasa and ESA have announced plans to bring back rocks and soil samples from Mars, while Nasa has three probes on the planet - two rovers and its Phoenix polar lander, which arrived in May.

The Phoenix has scraped ice from beneath the surface of Mars and is analysing samples in its laboratory to see if the planet has the right chemicals needed for life.

In 2013, ESA is planning to launch ExoMars - a robotic rover than will explore the planet's surface. If successful, it will be Europe's first mission to the Martian surface.

Scientists unveiled plans on Monday to bring back rocks from the Red Planet as a preliminary step to putting a man on Mars.

Professor Monica Grady, at the Open University, co-chaired the expert panel that wrote the mission proposal.

She said it was a vital next step before considering a crewed mission.

'If you can't bring a rock back you are not going to be able to bring people back,' she said.

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Trio of 'super-Earths' discovered.

Astronomers have identified a trio of so-called "super-Earths" - rocky planets between two and 10 times the mass of Earth.

The three new planets were detected using the Harps instrument at the La Silla Observatory in central Chile.

The star they circle is slightly smaller than our Sun, and is located 42 light-years away near the southern Doradus and Pictor constellations.

The discoveries were announced at an astronomy conference in Nantes, France.

When a planet orbits its star, it exerts a gravitational pull which causes the parent star to "wobble" around its centre of mass.

The High Accuracy Radial velocity Planet Searcher (Harps) spectrograph was able to measure this wobble to a very high precision over a period of five years.

This was vital because the perturbations caused by the planets were tiny.

"The mass of the smallest planet is one hundred thousand times smaller than that of the star," said co-author Francois Bouchy, from the Astrophysics Institute of Paris, France.

Chances are

The new worlds, which circle the star HD 40307, are 4.2, 6.7 and 9.4 times the size of Earth. They are named super-Earths because they are more massive than the Earth but less massive than Uranus and Neptune (which are about 15 Earth masses).

Using Harps data, the astronomers also counted a total of 45 candidate planets with a mass below 30 Earth masses.

This implies that one solar-like star out of three harbours such planets.

Astronomer Michel Mayor from the Geneva Observatory in Switzerland commented: "Does every single star harbour planets and, if yes, how many?

"We may not yet know the answer but we are making huge progress towards it."

Since the discovery in 1995 of a planet around the star 51 Pegasi by Michel Mayor and his colleague Didier Queloz, more than 270 exoplanets have been found - mostly around Sun-like stars.

The majority of these planets are gas giants, a bit like Jupiter or Saturn in our own Solar System. Current data shows that about one in 14 stars harbours this kind of planet.

The Harps instrument is attached to the La Silla 3.6m telescope in Chile. The facility is run by the European Southern Observatory (Eso) organisation.

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