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by ls65536 519 days ago
There's also a lunar occultation of Mars (which is near opposition itself, making it relatively bright) happening in a few days, and then again in February, which should be visible from parts of the northern hemisphere: https://in-the-sky.org/news.php?id=20250114_16_100
2 comments

Is there anything special to learn about occultations like this or are they just curiosities like alignments?
By precisely timing them you can measure/check various facts like distance, diameter and so on. In fact, if you time them precisely from different locations on earth you can determine the shape of the occulting body (e.g. an asteroid occulting a star). And on occasion you can get a 'grazing occultation', for example a star goes behind mountains on the moon resulting in it blinking on and off; observe from multiple latitudes and it's possible to recover the profile of the range.
Occultations can tell you about the atmosphere of the object in front. Depending on the rate at which the background object fades can tell you about atmospheric density, composition etc. If it disappears suddenly it indicates there may be no atmosphere.
Saturn is also playing peekaboo with the moon as well