The U.S. National Science Foundation has released the Daniel K. Inouye Solar Telescope’s first image of a sunspot, a spectacular, zoomed-in view captured on 28 January that shows a remarkably detailed view. While the 4-metre telescope is still undergoing tests and checkout, the image exhibits “a spatial resolution about 2.5 times higher than ever previously achieved, showing magnetic structures as small as 20 kilometres (12 miles) on the surface of the Sun,” said Thomas Rimmele, associate director at NSF’s National Solar Observatory, the organisation that operates the Inouye facility. The image is about 10,000 miles across, large enough for Earth to fit inside.
The Sunspot Number, the longest scientific experiment still ongoing, is a crucial tool used to study the solar dynamo, space weather and climate change. It has now been recalibrated and shows a consistent history of solar activity over the past few centuries. The new record has no significant long-term upward trend in solar activity since 1700, suggesting that rising global temperatures since the industrial revolution cannot be attributed to increased solar activity.
On Monday, 11 November 2019 just after 12:30pm GMT, suitably equipped observers in the British Isles can witness the start of a 3.7-hour spectacle that hasn’t been seen for three-and-a-half years — the silhouette of innermost planet Mercury crossing the face of the Sun. Here’s our online guide to observing this fascinating and comparatively rare event in complete safety.