[SatNews] The sun currently appears to be in one of the most active phases of that cycle.

Japanese space probe and observatory have recorded huge sunspot activity with a sunspot cluster 10 times the size of Earth, the Asahi Shimbun reported Thursday.

How do you tell the difference between a flare and a CME in NASA images? Flares look like bright flashes of light on the sun. Coronal mass ejections look like clouds zooming out into space. Image Credit: NASA/SDO

Images of the sunspot cluster were released by the National Astronomical Observatory of Japan (NAOJ) and the Japan Aerospace Exploration Agency (JAXA) on Wednesday.

The solar observation probe Hinode and NAOJ took pictures of the sunspots on October 16-30, before the sun's rotation obstructed the view. The sunspot cluster could be seen again on November 15, but it had shrunk to one-third of its peak size on October 26.

Sunspots appear in big clusters when the sun is most active. Large solar flares, a phenomenon triggered by sunspot activity, were also observed on the surface of the sun on six occasions in October.

Solar activity intensifies and then decreases over an 11-year cycle, according to the observatory. The sun currently appears to be in one of the most active phases of that cycle, it said.

The last time such a huge sunspot appeared was in 1990. That sunspot was 74 times the size of Earth and was observed over a four-month period.

Editor: Mu Xuequan