May 2026 – What’s Up!

Week of 25th May

• Astronomical Twilight does not end until the 21st July.
• Mercury (-1.1) is low to the north-western horizon this week, though take great care of the Sun if hunting the planet before sunset. Venus (-4.0) is a little higher and closer to the west, it sets at around 23:57 BST this week. Jupiter (-1.9) is higher again and sets at around 00:40 BST. There is a GRS transit at 21:56 BST on Wednesday.
• This week, with the bright Moon and no real darkness, we travel to Ophiuchus to search out four globular clusters. Start with M107 (+7.8) at 21 kly, then up a bit to M12 (+6.1) at 16 kly, left a bit to M10 (+6.6) at 14 kly, and finally left a bit more to M14 (+7.6) at 30 kly. Good luck hunting down these ancient clusters!
• The Moon is Full on Sunday, it is the second Full Moon in the month, so is a Blue Moon – the Blue Mead Moon.
• The Sun currently has 6 active regions and the sunspot number is 86.
• There are no visible evening ISS passes this week (click here for full ISS pass details).

Week of 18th May

• Astronomical Twilight ends at 00:07 BST at the start of the week and from Sunday, Astronomical Twilight does not end until the 21st July.
• Venus (-4.0) is the brightest object in the western sky just after sunset; the ‘evening star’ sets at around 23:48 BST. Jupiter (-1.9) sets at around 01:04 BST. There is an evening GRS transit at 22:46 BST on Friday.
• Get your telescope ready for some double stars in the Bootes area this week; start with Xi Bootis (+4.7) at a separation of 4.6″, then up a little to Izar, Epsilon Bootis (+4.7) at 2.9″ separation, then across to Zeta Coronae Borealis (+5.9) with a separation of 6.5″. A tough but beautiful selection of binary stars!
• The Moon is First Quarter on Saturday.
• The Sun currently has 6 active regions and the sunspot number is 83.
• There are multiple visible evening ISS passes this week (click here for full ISS pass details).

Week of 11th May

• Astronomical Twilight ends at 23:37 BST at the start of the week and at 00:01 BST by the end of the week.
• Venus (-4.0) is increasing in apparent magnitude in the western evening sky, now setting at around 23:35 BST. Jupiter (-2.0) is creeping ever further west, now setting at 01:28 BST. There is a well timed GRS transit on Friday at 21:56 BST.
• It’s all about Globular Clusters this week, those intriguing balls of some 100,000 stars. Start with M5 (+5.7) in Serpens at 24 kly, then on to M13 (+5.8) in Hercules at 23 kly, and finishing with M92 (+6.5) also in Hercules, but a little further away at 27 kly. Globulars make spectacular targets in binoculars or a telescope.
• The Moon is New on Saturday.
• The Sun currently has 5 active regions and the sunspot number is 81.
• There are multiple visible evening ISS passes this week (click here for full ISS pass details).

Week of 4th May

• Astronomical Twilight ends at 23:10 BST at the start of the week and at 23:33 BST by the end of the week.
• The Eta-Aquarid meteor shower peaks on Wednesday. It has a ZHR of around 40, but the radiant is very low in the sky, so don’t expect to see that kind of rate. The shower is caused by debris from comet 1P/Halley.
• Venus (-3.9) and Jupiter (-2.0) are slowly approaching each other in the western sky as they come to conjunction in early June. Venus sets at 23:17 BST and Jupiter sets at 01:52 BST.
• We search from zenith to horizon for this week’s deep sky challenge, starting overhead with M51, the Whirlpool Galaxy (+8.4) at about 28 million light years away in Canes Venatici. Slew to the southern border of Canes Venatici to find the globular cluster M3 (+6.3) at about 33,000 light years, and then towards the southern horizon into Virgo to search for the Sombrero Galaxy, M104 (+8.0) at 34 million light years.
• The Moon is Last Quarter on Saturday.
• The Sun currently has 8 active regions and the sunspot number is 133.
• There are multiple visible evening ISS passes this week (click here for full ISS pass details).