The comet is just a bit fainter than magnitude 2 and youll likely need binoculars or a small telescope to see it. But with optical aid, you should also spot the comets tail, which stands out best in photographs. NEOWISE recently passed Earth on July 23, when it was just 64.1 million miles (103.2 million kilometers) from our planet. As it continues to pull away from the Sun and Earths orbit, it will continue to dim, although observers can expect to enjoy this binocular object for at least the rest of the month.

Saturday, July 25The Moon reaches perigee, the closest point in its orbit around Earth, at 1:02 A.M. EDT. At that time, it will stand 228,889 miles (368,361 kilometers) from our planet. Tonight, our satellite is a 34-percent-lit waxing crescent in Virgo. Youll find it about one-third of the way on a line drawn from magnitude 1 Spica northwest toward magnitude 2.1 Denebola, the tail of Leo the Lion.

Look about 28.5 above the Moon to see another bright star: magnitude 0.1 Arcturus, Botes alpha star. Scan farther northwest to find the familiar Big Dipper asterism, which is part of a much larger constellation: Ursa Major the Great Bear.

Sunday, July 26Observers willing to brave the wee hours of the morning will be rewarded with a dark, moonless sky today. If its particularly clear, consider searching out the Dumbbell Nebula (M27), located in Vulpecula the Fox. This planetary nebula the result of an aging Sun-like star puffing away its outer layers late in life was discovered by Charles Messier in 1764. Youll find it amidst the dusty plane of the Milky Way, which is standing straight up from the southwestern horizon around 2 A.M. EDT. At that time, M27 is roughly 70 high and, although its a bit challenging with binoculars, a small scope will easily show it. A larger scope will bring out more detail. Most telescopes should reveal the nebulas bi-lobed structure, from which it gains its name.

Nearby is open star cluster NGC 6885 (Caldwell 37). This magnitude 6 cluster is roughly 7' across and can sometimes be seen barely with the naked eye. Its an excellent binocular or telescope target. Youll find it less than 5 north-northeast of M27.

Monday, July 27First Quarter Moon occurs at 8:33 A.M. EDT, making this evening is an excellent time to consider some lunar observing. With moonrise occurring in the afternoon, the Moon will still be high in the south at sunset and wont set until after midnight. Even a small telescope or pair of binoculars will bring out immense detail on our satellites face, which appears to observers on Earth as half in daylight and half in darkness during this phase. The line dividing the two is called the terminator, and its an excellent starting point for your observing campaign. Along this line, features will appear with the sharpest contrast, as taller mountaintops and crater rims catch the sunlight, while lower-lying areas remain in shadow. Along the terminator at First Quarter are several craters, including Archimedes, Ptolemaeus, Alphonsus, Arzachel, and Maginus.

Also visible are several darker seas, or maria, which are actually the smooth remnants of ancient lava flows. Among those that are easy to spot at First Quarter are the isolated Mare Crisium in the Moons upper right quadrant (for Northern Hemisphere observers), as well as Mare Serenitatis, Mare Tranquillitatis, and Mare Fecunditatis, which form much of the large, dark region to Crisiums lower left.

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The Sky This Week: Evening comets and morning meteors - Astronomy Magazine