Back in 2007, black spots were discovered on Mars that are so dark that nothing inside can be seen. Quite possibly, the spots are entrances to deep underground caves capable of protecting Martian life, were it to exist.
The unusual hole pictured above was found on the slopes of the giant Martian volcano Arsia Mons. The above image was captured three weeks ago by the HiRISE instrument onboard the Mars Reconnaissance Orbiter currently circling Mars.
The holes were originally identified on lower resolution images from the Mars Odyssey spacecraft, The above hole is about the size of a football field and is so deep that it is completely unilluminated by the Sun. Such holes and underground caves might be prime targets for future spacecraft, robots, and even the next generation of human interplanetary explorers.
1. Tissue slurry — Ontario, Canada This man-made lake in Terrace Bay, Ontario, Canada, is more than 500 metres long. It’s an aeration pond, part of the waste-treatment system at a factory that produces pulp for Kimberly-Clark tissues. “The treated water is returned to its source — often a river,” says Fair. Each yellow cone is an “agitator” that aerates and churns the liquid, assisting its breakdown. According to Worldwatch Institute figures, if recycled paper was used instead, 64 per cent less energy would be needed.and churns the liquid, assisting its breakdown. According to Worldwatch Institute figures, if recycled paper was used instead, 64 per cent less energy would be needed.
2. Fertiliser — Louisiana, US This emerald-tinted lake near Geismar, Louisiana, includes gypsum, uranium and radium. These chemicals result from manufacturing phosphorous fertiliser and are dumped into this impoundment to solidify. The world’s supplies of phosphates are dwindling and most are located in the US, China and Morocco. Unlike oil, however, there is no known renewable alternative for making fertiliser. “You think the resource crisis is in oil?” says Fair. “Think again.”
3. Spilled oil — Gulf of Mexico, US Fair captured this shot over the BP Deepwater Horizon spill at the Macondo well in June 2010, when 750m litres of oil leaked into the Gulf. “The stuff that was coming out of that well was all different colours,” says Fair. “We think of crude oil as being black — it’s all kinds of different colours and consistencies.” The bright red is the crude on the surface, reflecting light. The less viscous oil below the surface is purple-brown.
4. Liquid sulphur — Alberta, Canada At Fort McMurray in Alberta, Canada, a blood-red vein of liquid sulphur is pumped on to a bed of solidified yellow sulphur. The element is one of the major by-products of tar-sand upgrading and there is now an abundance of stocks globally. With prices low, producer Syncrude isn’t selling — it’s storing it in giant pyramids. Liquid sulphur, at around 200°C (its melting point is 115°C), is pumped into fenced-off compounds and left to harden.
5. Aluminium sludge — Louisiana, US This slurry pit is where the solid and liquid by-products of aluminium manufacture are separated. The process involves refining bauxite ore, which produces alumina. The waste includes bauxite impurities, heavy metals and sodium hydroxide (one of the chemicals used during processing). Fair estimates that the red-brown sludge has a pH of about 13, “meaning if you touch it, it burns the skin off”.
6. Fertiliser slurry — Louisiana, US This wintry-looking scene is a mix of lead, ammonia, mercury and ethanol — by-products of phosphate fertiliser production. “It’s a giant lake of waste,” says Fair, who shot the image 80km west of New Orleans in 2005. Owned by Mosaic Fertilizers, the plant, called Uncle Sam, has violated the US Clean Water Act nine times. The slurry pit is less than 3km from the banks of the Mississippi.
The Derweze area is rich in natural gas. While drilling in 1971, Soviet geologists tapped into a cavern filled with natural gas. The ground beneath the drilling rig collapsed, leaving a large hole with a diameter of 70 metres (230 ft). To avoid poisonous gas discharge, it was decided to burn it off. Geologists had hoped the fire would use all the fuel in a matter of days, but the gas is still burning today. Locals have dubbed the cavern “The Door to Hell”.
Photographer James Appleton, 23, from Cambridge, risked his life trekking solo to the area and captured these incredible shots. The Cambridge University graduate spent five days observing the first phase of the eruption from a shack in nearby Fimmvorouhals mountain pass. He spent seven hours battling biting wind and freezing temperatures to get as close to the eruption as possible, against the advice of local guides. Despite being trapped inside a shack there for 48 hours, Mr Appleton managed to trek within 100ft of the volcano.
Thunderstorms produce a lot of weird things, which are often easy to miss amid the urgency of tornadoes, floods and lightning. But before a storm arrives, or sometimes out of the blue, rare “roll clouds” like this one command attention as they float ominously overhead.