Starwatch: moon will obscure brightest star in Virgo

This week the first quarter moon will make a close pass of Spica, the brightest star in the constellation Virgo, the virgin. The chart shows the view looking west/south-west from London at 11pm (BST) on the evening of 13 July.

The moon will creep closer to the star as midnight passes and we move into the early hours of 14 July, but the constellation will be setting fast too. The moon will be about 7.5 days old and almost exactly 50% of its visible surface will be illuminated.

For observers in much of North and Central America, the moon will pass directly in front of Spica, obscuring it from view. Such an occultation is not unusual between this pair of celestial objects but nevertheless, it is a remarkably evocative sight to watch the bright star disappearing behind the moon.

It is best seen using a pair of binoculars – but remember never to look at the sky with binoculars or any other optical aid when the sun is above the horizon. Permanent blindness can occur.

To check if the occultation is visible where you are located, visit in-the-sky.org and enter your location using the button on the right-hand side of the page.