As June begins, the moon is already in its waxing gibbous phase and disrupting dark evening skies. It reaches before the end of June’s first week and rapidly leaves evening skies to darkness from the 9th to 20th of the month.
If you have chance, early mornings provide the opportunity to see some of the tougher items on the Lunar 100 list, during the moon’s waning gibbous phase. Last quarter is reached on the 13th followed by the waning crescent gradually leaving morning skies.
The entire night is dark around the new moon on the 21st, which presents our last chance of the month for truly dark evening skies.
We end the month with a first quarter on the 28th. The days either side of first quarter always present fantastic views of the lunar surface, so now is a great time to try and find members of the Lunar 100. For the final days of June, the moon is waxing gibbous and brightening in the evening but setting a couple of hours before dawn.
There are two windows for observing librations this month. The first is in the evening from June 03 to 06. Librations move around the south east quadrant of the moon, from the 6 o’clock position on the 3rd to the 3 o’clock position on the 6th. Our second libration opportunity is a tight one – we’ll just get chance to spy it in the short window between moon rise at 3:30 am and dawn on June 17th. In this case, the top of the moon is tilted towards us, around the 11 o’clock position. See more detail at the bottom of the page.
|Dark Evenings||Dark Mornings||Dark Night||Evening Moon||Morning Moon||Librations|
|9th – 20th||19th – 24th||17th – 20th||1st – 4th, 23rd – 30th||3rd – 8th||3rd – 6th, 17th|
Whether you are planning to observe the moon, or you want to make sure to avoid it, use the table below to discover when the moon will be above the horizon in March. The ‘Illumination’ column shows how bright it is going to be – the higher the %, the brighter the moon.
The following chart shows a visualisation of when the moon is above the horizon and below. This should make it easier for you to plan which nights offer the darkest skies and which provide the best opportunity for observing the moon itself.
The two pictures below, from SkySafari 6, show the last quarter moon at 5am on June 13th, about 30° above the southeast horizon near Mars, and the first quarter moon at 10pm on 28th June, about 35° above the horizon. Click on the pictures for full screen versions.
The moon wobbles as it orbits Earth. These wobbles are known as librations and mean that we can actually see around 59% of the lunar surface over the course of a month. Keen moon watchers look for these librations so they can spy craters not normally visible to us.
The images below are favorable librations for observing at the date shown in the caption. The best librations for June happen on the 03-06 and 17 June. Between the third and sixth of June, the southeast quadrant is shown to us, travelling from south on the third to east on the 6th. On the 17th, the region just west of north is revealed.
Click images for a full size version. Images from CalSky.
The pictures below are from CalSky and show lunar librations at first and last quarters. To read them, refer to the red dots and red intersecting lines.
The red lines on the lunar surface show where the central lines of longitude and latitude cross. The red dot in the middle of the picture shows where they would be if there was no libration.
The red dot on the limb (edge) of the moon shows which part of the lunar surface is most tipped towards us – where we may see parts of the lunar surface not normally visible.
Click the image for a larger version