sunspots – Astronomy Now

Set your filtered sights on the Sun

25 June 2024 Mark Armstrong

Summer is the season for a spot of solar observing and sunspots, probably the Sun’s most fascinating phenomena, are easier to see than you might think.

Inouye Solar Telescope captures spectacular first sunspot image

7 December 2020 Astronomy Now

A spectacular image of a sunspot released by the Daniel K. Inouye Solar Telescope, the world’s largest, shows a wealth of detail with a resolution 2.5 times higher than previously achieved.

Giant star spots, not dust, likely culprit in dimming of Betelgeuse

29 June 2020 Astronomy Now

The pronounced dimming of the red giant Betelgeuse likely was caused by huge star spots, not by intervening dust, researchers say.

How to safely observe Mercury crossing the Sun on 11 November

7 November 2019 Ade Ashford

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.

ALMA starts observing the Sun

17 January 2017 Stephen Clark

New images taken with the Atacama Large Millimeter/submillimeter Array in Chile have revealed otherwise invisible details of our Sun, including a new view of the dark, contorted centre of a sunspot that is nearly twice the diameter of the Earth.

All’s quiet on the Sun

3 December 2016 Astronomy Now

This week the Sun was hitting its lowest level of solar activity since 2011 as it gradually marches toward solar minimum. See a near spotless Sun revolve in this video from the Solar Dynamic Observatory.

Proxima Centauri might be more Sun-like than we thought

11 October 2016 Astronomy Now

Astronomers recently announced that the nearby star Proxima Centauri hosts an Earth-sized planet in its habitable zone. Proxima Centauri is a small, cool, red dwarf star only one-tenth as massive and one-thousandth as luminous as the Sun. However, new research shows that it is Sun-like in one surprising way: it has a regular cycle of starspots.

‘Starspot’ images of nearby star give insights into early Sun

4 May 2016 Astronomy Now

Astronomers have used interferometry to create a time-lapse of the nearby star zeta Andromedae over one of its 18-day rotations that show starspots — sunspots outside our solar system. The pattern of spots on the star is very different from their typical arrangement on our Sun, challenging current theories of how stars’ magnetic fields influence their evolution.

Sun-like star shows magnetic field was critical for life on early Earth

16 March 2016 Astronomy Now

Nearly four billion years ago, life arose on Earth. Life appeared because our planet had a rocky surface, liquid water, a blanketing atmosphere and a protective magnetic field. A new study of the young, Sun-like star Kappa Ceti shows that a magnetic field plays a key role in making a planet conducive to life.

Corrected sunspot history suggests climate change not due to natural solar trends

8 August 2015 Astronomy Now

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.