Read our guide on how to calculate and observe lunar occultations<\/a><\/em><\/strong><\/p> While lunar occultations of planets are fairly rare events, the Moon occults bright stars quite regularly.<\/p> In fact, we can work out how many naked eye stars will be hidden by the Moon in a year by looking at the path the Moon takes through the sky.<\/p> This is centred on the apparent path of the Sun against the background stars, called the ecliptic<\/a>, but tilted at a little over 5\u00b0.<\/p> The Moon covers around 0.5% of the night sky in its yearly journey, equating to about 850 naked eye stars including bright ones like Aldebaran<\/a>, Regulus<\/a>, Spica and Antares<\/a>.<\/p> In any one month, you can be pretty sure that the Moon will occult a few decent stars.<\/p> When the Moon occults a star, it\u2019s like the star has been switched off: one moment it\u2019s there, the next it\u2019s gone.<\/p> This is more noticeable before full Moon, when the Moon is \u2018waxing\u2019. Then, the part that first covers the star \u2013 the \u2018left-hand\u2019 edge \u2013 is dark and unlit.<\/p> It\u2019s more impressive than seeing the star being hidden by the Moon\u2019s bright edge.An occulted star will disappear almost immediately, and this shows that the Moon has no atmosphere.<\/p> If there were gases enveloping the Moon, an occulted star would shimmer and fade as it approached the lunar disc before finally fading out.<\/p> A lunar occultation of Venus is quite a sight, since through a telescope you\u2019ll be able to see a phase on both the planet and the Moon. Sometimes Venus is bright enough to make the event visible through a scope in daylight.<\/p> It’s quite something to see Jupiter skim across the lunar limb. The gas giant peeping through lunar valleys can be a beautiful sight in 4- to 6-inch telescopes.<\/p> There\u2019s a happy coincidence the next time the Moon moves in front of the Red Planet at night. It will be the subject of a lunar occultation the very day that the planet is at opposition<\/a>, when it appears at its brightest and largest, on 8 December 2022.<\/p> It\u2019s an awe-inspiring sight to watch Saturn and its rings slip behind the Moon\u2019s dark limb through even a small telescope. In the UK, the next such event is occurring on 21 August 2024.<\/p> A star or planet can appear to come into contact with the Moon anywhere along the leading, eastern edge of its round disc.<\/p> However, sometimes the Moon only just brushes objects with its edge. These truly rewarding events are known as \u2018grazing occultations\u2019.<\/p> They enable us to see that the Moon\u2019s surface is marked with mountains and craters.<\/p> During a lunar graze, the star or planet being occulted will blink in and out of view as it passes behind the mountains and valleys along the Moon\u2019s limb.<\/p> However, these events are only visible from a narrow path on the Earth, so you have to be in exactly the right place to see one; too far one way and there will be no occultation, too far the other and the object will be completely hidden.<\/p> Observations of an occultation in astronomy can also be used for scientific purposes, to refine the profile of the Moon and its orbit and to reveal hidden multiple stars.<\/p> For scientifically useful records, find the latitude and longitude of your observing position.<\/p> Watch the occultation through a small telescope, timing it with a stopwatch that can record split\/lap times. As soon as the star disappears, start the stopwatch.<\/p> When it emerges, hit the split\/lap button and write down the elapsed time, but keep the stopwatch running. <\/p> Stop the stopwatch a short time later while keeping an eye on an accurate clock. Note down the time you stopped the stopwatch (eg 22:32:06).<\/p> To find the time of day (or night) when the star disappeared, subtract the final time shown on the stopwatch from the time you noted down from the clock.<\/p> To get the time when the star emerged, add the split\/lap time. For this purpose it might be worth keeping an astronomy logbook<\/a>. You can submit your recordings to the Society for Popular Astronomy\u2019s Occultation Section<\/a>.<\/p>Lunar occultations of stars<\/strong><\/h2>
![\"Lunar](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/48\/2020\/05\/UK-summer-ecliptic-91416c3.jpg\" "\\"\\"\/")
![\"Waxing](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/48\/2019\/10\/hs09_DavidBryant_Occultation-26ffc1f.jpg\")
Lunar occultations of planets<\/strong><\/h2>
Venus<\/b><\/a><\/h3>
![\"A](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/48\/2020\/05\/Photograph-lunar-occultation-venus-06-3e538aa-e1611661459139.jpg\" "\\"\\"\/")
Jupiter<\/b><\/a><\/h3>
![\"A](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/48\/2019\/02\/Copy-of-P1010012_0-d77b6c4.jpg\" "\\"\\"\/")
Mars<\/b><\/a><\/h3>
![\"A](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/48\/2020\/10\/01.RicardoTolentino_MarsMoon-156891b-e1611581734696.jpg\" "\\"\\"\/")
Saturn<\/b><\/h3>
![\"Lunar](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/48\/2021\/01\/GettyImages-102724659-f8f05a4-e1611670326402.jpg\" "\\"\\"\/")
Grazing occultations<\/strong><\/h2>
![\"A](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/48\/2020\/12\/07.ArisBottas_DaytimeOccultationVenusMoon-4955a35.jpg\" "\\"\\"\/")
How to record an occultation in astronomy<\/h2>