The planet Mercury has long enjoyed a certain glamorous sheen thanks to it being named after the fleet-footed messenger of the Roman gods.
Now, however, it seems in danger of gaining an altogether less appealing association – as a celestial reminder of what happens if you don’t keep up with the dusting.
American scientists believe that they have solved the mystery of why, compared with the Moon, its nearest airless neighbour, Mercury has a dark and decidedly non-silvery surface. The reason, they say, is that the planet is coated in billions of years’ worth of carbon dust, after millennia upon millennia of being “dumped on” by passing comets.
The repeated showers of dusty “stealth-darkening agent”, they suggest, have in effect turned Mercury into “a painted planet”.
Where to explore in the solar system
Where to explore in the solar system
1/10 Mars - Olympus Mons
Olympus Mons is the largest volcano in the Solar System. At 22km high Olympus Mons is nearly three times as high as Mt Everest
2/10 Mars - Mount Sharp
Mount Sharp is the current focus point of the Mars Science Laboratory’s Curiosity rover. Sitting at the forefront of Martian research this location will hopefully unlock the secrets of Mars’s past.
3/10 Ida and Dactyl
Nestled deep within the asteroid belt is the asteroid 243 Ida. During a fly by of the Galileo space probe it was discovered that Ida had a companion. Orbiting around Ida was a tiny moon that was named Dactyl.
4/10 Jupiter - The Red Spot
Getting tired of leisurely cruises through the Caribbean? Why not float a dirigible through one of the oldest known storms in the Solar System. Jupiter’s Great Red Spot is large enough to contain three Earths and has been present for over 300 years.
5/10 Moon - Sea of Tranquility
As the landing site of the first ever humans to set foot on the Moon who wouldn’t want to walk in the footsteps on Neil Armstrong on the Sea of Tranquility?
6/10 Europa - Underwater seas
Europa’s underwater seas are one of the strongest candidates for potential life outside Earth. Scientists are waiting the day we can probe their icy depths.
7/10 Titan - Methane Lakes
Saturn’s Moon Titan is home to a nice thick atmosphere. Similar to the Earth it supports a full weather cycle. Unlike the Earth, rather than using water, Titan’s cycle is based on methane, often found in gas cookers here on Earth.
8/10 Mimas, the Death Moon
What better location for a holiday snap. The large Herschel crater on Mimas gives this moon an appearance of a certain dark lords ultimate weapon. When viewed from the right angle it appears that the Death Star is in orbit around Saturn.
The thick clouds of Venus make it an extremely mysterious place. It also has some of the most extreme weather we can find. Runaway greenhouse gases have shrouded the planet in a thick layer of cloud, heating it to nearly 600°C. It is also home to sulphuric acid rain and crushing atmospheric pressure. Make sure you pack a sturdy umbrella!
10/10 Oceans of Earth
One of the most unexplored places in the Solar System is our own oceans. 70% of the Earth is covered in ocean and as of yet we have only explored around 10% of them. With so much water to explore who knows what we may find lurking in the depths.
The dim surface of the planet closest to the Sun, has long puzzled astronomers. Since it has the thinnest atmosphere of all the planets in the solar system, one possibility was that it was darkened by the effects of solar winds and the impacts of micro meteorites.
Both processes, however, would leave a thin, dark coating of tiny, dark iron particles, and analysis found that there were in fact very few such particles on Mercury’s surface.
Now research, published in Nature Geoscience and conducted by Megan Bruck Syal at Brown University in Rhode Island, has produced another possibility. “It’s long been hypothesised that there’s a mystery darkening agent that’s contributing to Mercury’s low reflectance,” she said. “One thing that hadn’t been considered was that Mercury gets dumped on by a lot of material derived from comets.”Reuse content