June 2025 – What’s Up!

Week of 30th June

• Astronomical twilight does not end until 21st July.
• The Earth reaches aphelion on Thursday, our most distant orbital point from the Sun. Clearly the seasons have nothing to do with our distance from the Sun, but have everything to do with the tilt of the Earth’s axis!
• Mercury (+0.6) reaches Greatest Eastern Elongation on Friday, making it well placed for observation. It is still a challenge to spot in the west just after sunset, which is at 21:25 BST, at an altitude of about 10°. Take care of the Sun if searching with binoculars or a telescope.
• This week spend some time with the dolphin, Delphinus. Start with the spectacular double star, Gamma Delphini (+4.3), with a separation of 9 arcseconds. Then on to two globular clusters discovered by William Herschel; the first is NGC 6934 (+8.8), at 50,000 light years from Earth, the second is the challenging NGC 7006 (+10.6), at 130,000 light years away!
• The Moon is First Quarter on Wednesday.
• The Sun currently has 8 active regions and the sunspot number is 103.
• There are multiple visible evening ISS passes this week (click here for full ISS pass details).

Week of 23rd June

• Astronomical twilight does not end until 21st July.
• Mercury (+0.0) reaches its highest point in our evening sky this week, sitting at an altitude of 11° in the west. Hunt down the tiny planet in the dusk after sunset, which is at around 21:27 BST. Take care of the Sun if searching before it has fully set.
• Early risers can enjoy multiple planets this week; Saturn (+1.0) and Neptune (+7.9) rise side by side at around 01:05 BST, followed by Venus (-4.2) at 02:40 BST, the Sun rises at about 04:50 BST.
• Three planetary nebulae are the deep sky challenge in the dark, Moon free skies this week; first up is the cosmic smoke ring, M57, the Ring Nebula (+8.8) in Lyra, then across to M27, the Dumbbell Nebula (+7.1) in Vulpecula, and finally to NGC 6826, the Blinking Planetary Nebula in Cygnus. They range in apparent size from 1.4 to 8 arcminutes, all small, so a telescope and relatively high magnification will be required.
• The Moon is New on Wednesday.
• The Sun currently has 6 active regions and the sunspot number is 87.
• There are no visible evening ISS passes this week (click here for full ISS pass details).

Week of 16th June

• Astronomical twilight does not end until 21st July.
• The June Solstice, or Summer Solstice here in the Northern Hemisphere, is at 03:42 BST on Saturday. This is when the Sun reaches it’s most northerly declination of +23.5°, appearing to stop at its highest altitude before sinking back towards the celestial equator. We will enjoy the longest hours of daylight and the start of astronomical summer.
• Mars (+1.4) passes by Regulus, Alpha Leonis (+1.4), the brightest star in the constellation Leo in the first part of this week, making a beautiful conjunction.
• Follow the central line of the Northern Cross in Cygnus for this week’s binocular deep sky objects. Start at the beak of the Swan with double star Albireo (+3.1), a celestial gem! Then to the body for the open cluster M29 (+6.6), sometimes described as a ‘mini Plough’. Finish near Deneb, the Swan’s tail, with NGC 7000 (+4.0), the North America Nebula, a patch of the Milky Way that resembles the USA!
• The Moon is Last Quarter on Wednesday.
• The Sun currently has 7 active regions and the sunspot number is 136.
• There are no visible evening ISS passes this week (click here for full ISS pass details).

Week of 9th June

• Astronomical twilight does not end until 21st July.
• Early risers are treated with three planets this week; Neptune (+7.9) and Saturn (+1.1), separated by just under 2°, rise at around 02:00 BST, with sunrise at around 04:50 BST this week. Venus (-4.2) dominates the morning sky, rising at around 03:00 BST.
• In the summer months, the ecliptic lies close to the southern horizon at night placing the Full Moon low in the sky, so despite moonlight and the lack of Astronomical Darkness, there are still plenty of celestial delights to enjoy. It’s all about the stars this week, starting with the Coathanger asterism (+3.6) in Vulpecula in the middle of the Summer Triangle, best observed in binoculars. Then up a little to stunning double star Albireo (+3.1) in Cygnus, before finishing with another great double star system, Epsilon Lyrae (+5.0), the Double Double in Lyra.
• The Moon is Full on Wednesday – the Strawberry Moon.
• The Sun currently has 5 active regions and the sunspot number is 103.
• There are no visible evening ISS passes this week (click here for full ISS pass details).

Week of 2nd June

• Astronomical twilight does not end until 21st July.
• Mars (+1.3) is gradually exiting this apparition; it now sets at around 01:25 BST and is only 5.5 arcseconds in apparent size. Venus (-4.3) continues to dominate the morning sky, rising at 03:17 BST. Look a few degrees towards the southeast to find Saturn (+1.1) with its ring system tilted towards the north following its equinox.
• The Summer Triangle is creeping higher now and this week’s deep sky objects can all be found on its western side in Lyra. Start with the wonderful Double Double, Epsilon Lyrae (+5.4) just to the northeast of Vega (0.0), can you split all four stars?! Then on to M57, the Ring Nebula (+8.8), a planetary nebula that looks just like a whispy smoke ring in the eyepiece. Finish a few degrees to the south with M56 (+8.3), a globular cluster 32,000 light years away from Earth.
• The Moon is First Quarter on Tuesday.
• The Sun currently has 5 active regions and the sunspot number is 96.
• There are no visible evening ISS passes this week (click here for full ISS pass details).