As the weather warms in the northern hemisphere, there’s nothing quite like a night of stargazing. While many of us are unable to travel for astronomy meetups and star parties, we can still set up in our backyards and local parks to enjoy the May night sky.
This month, we’ll receive a series of astronomical treats: planetary close approaches, meteors, and even a few special events with the Moon.Never mind the fact that the Milky Way core is slowly rising as the month goes on and you’ll be able to see the that too. The May new moon takes place on May 30th, which is another great night for seeing the darkest skies possible this month.
Throughout this post, I’ve noted where you need binoculars or a telescope to fully appreciate the astronomical event. If you need guidance on investing in a piece of stargazing equipment, be sure to check my list of recommended telescopes and binoculars at every price point.
Without further ado, here are the May night sky events to mark on your astronomical calendar.
This post was originally published in May 2019, and is updated annually, most recently in April 2022.
Featured photo credit: Willi Winzig via Flickr
May 6 – Peak of the η–Aquariid Meteor Shower
Meteorites always wow the crowds, and in May we have two decent chances for such celestial showers. The first one is the Eta Aquariid Meteor Shower, which peaks around May 6th this year. This is a better show for earthlings near the equator, since the constellation Aquarius – which serves as the meteor shower’s radiant point – will be fairly low in the southern sky.
You can catch this show between late April through most of May every year, but the peak will be around the 6th of May. The Eta Aquariids typically produce about 40 meteors per hour; not a bad way to kick off the month! Best of all, the Moon will be a waning crescent, so unlikely to produce much interference.
May 8 – Peak of the η-Lyrid Meteor Shower
The Eta Lyrid (η-Lyrid) meteor shower runs from May 3rd to 14th each year, but in 2021, the night of peak activity is likely to occur on May 8th. On this night, you can look in the general direction of the radiant point in the constellation Lyra to try and spot Eta Lyrids streaking across the sky.
While the Eta Lyrids are not a particularly active meteor shower (you can expect an average of 3 meteors per hour during the peak), it’s possible to try and see these meteors both pre-dawn on the 8th and that evening too.
May 15 – Total Lunar Eclipse
After the Partial Solar Eclipse on April 30th, we can naturally expect a lunar eclipse about two weeks later. This eclipse will be visible overnight on May 15th to 16th, and can be seen from all of South America and the eastern half of North America. Other parts of the world, including the rest of North America, Africa, and Europe, will be able to see a partial lunar eclipse either earlier in the evening on the 15th or in the pre-dawn hours of the 16th depending on time zones.
Check out my guide to viewing this lunar eclipse, which will be updated about two weeks before the event.
May 17 – Conjunction of Mars & Neptune
After the lunar eclipse mid-month, the rest of the astronomical events of note in May are all related to conjunctions and close visual approaches between various members of our solar system family. First up is a conjunction between Mars and Neptune on the night of May 17th.
What makes this conjunction notable is the fact that allows you to use Mars to planet-hop to spot Neptune; you’ll need binoculars or a telescope to do so though. The two will appear quite close together in the sky, just 0°34′ apart, which is perfect if you are using astronomical binoculars to try and spot the pair (you may need to adjust your telescope to shift from Mars to Neptune depending on the power of your scope).
May 21 – Conjunction of the Moon & Saturn
Next, the Moon and Saturn have a close visual approach on the night of May 21st to 22nd (the actual closest approach is just after midnight on the 22nd, but for clarity, I put the date of this event as May 21st so you could stargaze before observing these two celestial bodies).
While the Moon and Saturn won’t be anywhere as visually close as Mars and Neptune a few nights ago, they’ll still be within 5° of one another (4°27′ to be exact). The Waning Gibbous Moon will be at is Third Quarter phase and nice for observing before you turn your attention to Saturn and its lovely rings.
May 24 – Conjunction of the Moon, Mars & Jupiter
Next up, the Moon gets close (from our perspective) with Mars and Jupiter in turn. The first close approach – between the Moon and Mars – will take place during the daylight hours for most viewers; they’ll be just 2°46′ apart at their closest but will still appear near each other by the time the sun goes down. Then, a few hours later, the Moon appears close to bright Jupiter, just 3°14′ apart.
This is another great night to pull out your astronomy equipment to get a better view of these three neighboring solar system objects. Additionally, the Moon will be a Waning Crescent and its terminus should be lovely for observation.
May 27 – Lunar Occultation of Venus
For something slightly different, night sky viewers in Southeast Asia will get a treat on the night of May 27th. For those in the area where it will be visible, a Lunar Occultation will occur on the morning of May 27th (from about midnight UTC until 05:30 UTC).
For the rest of us, the Moon and Venus will appear close to one another in the sky, though we won’t get the treat of watching Venus slip behind the sliver of Waning Crescent Moon.
May 28 – Conjunction of Mars & Jupiter
Finally, after having separate close visual approaches with the Moon a few nights earlier, Mars and Jupiter will have their own close approach. The pair will appear just 0°38′ apart in the night sky – even closer than Mars and Neptune appeared earlier in the month – after sunset on the night on May 28th.
While Mars and Jupiter are both visible to the un-aided eye, this is the final great night in May to grab your telescope or binoculars and get a closer look at these two planets.
Do you have questions about these astronomical events in the May night sky? Let me know in the comments!