In the context of space, the term ‘cloud’ can mean something rather different from the fluffy white collections of water in the sky or a way to store data or process information. Giant molecular clouds are vast cosmic objects, composed primarily of hydrogen molecules and helium atoms, where new stars and planets are born. These clouds can contain more mass than a million Suns, and stretch across hundreds of light-years.
Mercury is generally something of a challenge to observe, but the run-up to a particularly favourable easterly elongation occurring on 30 July provides ample opportunities for locating the innermost planet in the evening sky — particularly from the Southern Hemisphere, where a prominent celestial marker in the form of a 2-day-old Moon passes close by on 25 July.
Two days after NASA’s Juno spacecraft streaked over Jupiter’s Great Red Spot, pictures of the solar system’s largest, most powerful storm, have been transmitted to Earth, giving eager scientist close-up views of the 10,000-mile-wide anticyclone where 400-mph winds have been howling for at least 187 years and possibly much longer.
A new treasure trove of planets, ranging from worlds with small masses and short orbital periods of less than 15 days to super-Earth-sized planets that can take up to a year to orbit their star, has been discovered by astronomers using the world’s most successful ground-based planet-finding instrument.
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