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Mercury puts on one of its best apparitions for 2024 this month.<\/em><\/p>\n Where have all of the planets gone? The late evening fall of dusk in early July also sees a sky seemingly vacant of familiar naked eye planets. Mars, Jupiter and Saturn are now denizens of dawn, and will stay that way for most of the remainder of 2024.<\/p>\n But two challenging planets are now emerging low to the west at dusk: Mercury and Venus. The two interior worlds are now mounting a slow return, as the hunt is now on the recover the two after sunset.<\/p>\n <\/p>\n Mercury\u2019s July apparition in particular is an interesting one, and one of the best of six for observers worldwide. This is mainly because the planet is headed towards aphelion 0.4667 Astronomical Units (AU) from the Sun on July 27th<\/sup>, just five days after greatest elongation. At greatest elongation on July 22nd<\/sup> , Mercury will display an 8\u201d diameter 45% illuminated disk, shining at a respectable magnitude +0.3.<\/p>\n To be sure, Mercury doesn\u2019t look like much more than a dot in a telescope, even at high power\u2026 but part of the thrill of finding the illusive world lies in knowing what your actually seeing.<\/p>\n To be sure, Mercury has been known of since antiquity and isn\u2019t at all that <\/em>hard to see, if you know exactly where and when to look for it. A low flat horizon looking west at dusk certainly helps.<\/p>\n The often told tale that Nicolas Copernicus never saw Mercury is probably apocryphal. Looking at the diminutive world through the telescope reveals a cycle of Moon-like phases\u2026 and not much else. Mercury\u2019s distinction as the innermost world in the solar system always assures that it always lingers low down in the murk of the atmosphere at dusk or dawn. This makes it too blurry to glimpse much in terms of surface detail. It wasn\u2019t until the advent of space exploration that we knew much more about Mercury. NASA\u2019s Mariner 10 made two brief flybys past the planet in 1974 and 1975, revealing an airless, cratered world 1.4 times the size of our Moon. Since then NASA\u2019s Mercury MESSENGER revealed the planet in greater detail, becoming the first spacecraft to enter orbit around the world in 2011. Meanwhile, the joint ESA\/JAXA BepiColombo mission has thus far made three flybys past Mercury, and will enter orbit in late 2025.<\/p>\nExploring Mercury<\/h2>\n