This image released this week by the European Space Agency was taken over part of northeast Greenland’s coast and combines three images from the satellite Sentinel-1A’s radar over three months.
The shades of grey on the left side of the image depict the static landmass, while colours on the right show changes in sea-ice type and cover between the three radar scans.
Near the centre-left we can see the Zachariae Isstrom glacier, which is losing around five billion tonnes of ice a year to the ocean.
Zachariae’s dynamics have been changing over the past few years, calving high volumes of icebergs which will inevitably affect sea levels. It is estimated that the entire Zachariae Isstrom glacier in northeast Greenland holds enough water to raise global sea levels by more than 46 centimetres.
The polar regions are some of the first to experience and visibly demonstrate the effects of climate change, serving as barometers for change in the rest of the world.
JOHN GURZINSKI / AFP / Getty Images
Hyperloop’s first test
Sand rises from the track as a test sled slows during the first test of the propulsion system at the Hyperloop One Test and Safety site this week in North Las Vegas, Nevada.
The sled accelerated to 187 kilometres per hour in just 1.1 seconds. The demonstration represents a very early proof of concept of Tesla chief Elon Musk’s futuristic rail transit concept that could one day ferry passengers at near supersonic speeds.
NASA / Jeff Schmaltz, LANCE / EOSDIS Rapid Response.
Bloom in the Black
Sea
Light blue colours toward the middle of this natural-colour image of the Black Sea, taken by Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on NASA’s Aquasatellite, are likely the result of blooming phytoplankton.
One type of phytoplankton found here is the coccolithophores – microscopic plankton that are plated with white calcium carbonate. Early May might be too soon to see them blooming here in large numbers. Their signature milky blue swirls are more common in summer.
However, climate change is shifting the timing of phytoplankton blooms around the world. Only a surface sample can confirm the exact composition of a bloom.
Other factors could also contribute to the myriad colors. The middle of the sea is quite deep – more than 2,000 metres (7,000 feet) in parts.
In this region, surface water generally does not mix with the deeper, saltier, oxygen-free waters. But in the shallows closer to the coasts, some colour could be due to the mixing and stirring of bottom sediments. Browns and greens are also common near the shore after a heavy rain and at the mouth of large rivers such as the Danube in Germany.
NASA’s Goddard Space Flight Center / SDO / Genna Duberstein
Mercury transit
Early this week Mercury passed directly between the Sun and Earth. This event – which happens around 13 times each century – is called a transit.
NASA’s Solar Dynamics Observatory, or SDO, studies the Sun 24/7 and captured the entire seven-and-a-half-hour event.
This composite image of Mercury’s journey across the sun was created with visible-light images from the Helioseismic and Magnetic Imager on SDO.
Dan Kitwood / Getty Images
Your very own dinosaur?
Dinosaur skeletons are up for auction as the Netherlands’ internationally acclaimed Emmen Zoo’s Natural History Collection goes on sale.
An auction house employee poses between skeletons of Hyrachyus (left) and the duck-billed dinosaur Harpocrasaurus stibengi (right), during a preview of a forthcoming sale in June at Summers Place Auction House Billingshurst in England.
Harpocrasaurus is estimated to cost £50,000 – £80,000 (US$72,000 – $115,000) while Hyrachyus may bring in £4,000-£6,000 (US$5,800 – $8,700).
