Friday, May 24 - Be sure to look to the western horizon just after the Sun sets for a spectacular sight?Jupiter, Venus and Mercury are moving together! It's a great observation that doesn't require any optical aid to enjoy.
Full Moon is only hours away and that mean bright skies for observing tonight. It might toast nebulae and galaxies, but not this "flare star". For those who like curiosities, our target for tonight will be 1.4 degrees northwest of 59 Leonis, which is itself about a degree southwest of Xi. While this type of observation may not be for everyone, what we are looking for is a very special star: a red dwarf named Wolf 359 (RA 10 56 28.99 Dec +07 00 52.0).
Wolf 359. Palomar Observatory Courtesy of Caltech
Discovered photographically by Max Wolf in 1959, charts from that time period will no longer be accurate because of the star's large proper motion. It is one of the least luminous stars known, and we probably wouldn't even know it was there except for the fact that it is the third closest star to our solar system. Located only 7.5 light-years away, this miniature star is about 8% the size of our Sun, making it roughly the size of Jupiter. Oddly enough, it is also a flare star-capable of jumping another magnitude brighter at random intervals. It might be faint and difficult to spot in mid-sized scopes, but Wolf 359 is definitely one of the most unusual things you will ever observe!
Saturday, May 25 - Don't forget to check the western horizon just after the Sun sets for the appearance of Jupiter, Venus and Mercury. The trio is fast coming together and headed towards a planetary conjunction!
It's the official date of the May Full Moon. While it actually occurred on May 24th during the wee hours, there's no reason we can't celebrate "Full Flower Moon" tonight. Agricultural literature refers to it as the "Full Corn Planting Moon", or the "Milk Moon". No matter what it's named, Moonrise is majestic to watch. Participate in a Lunar Club Challenge and do some outreach work by demonstrating "Moon Illusion" to someone. We know it's purely psychological and not physical, but the fact remains that the Moon seems larger on the horizon. Using a small coin held at arm's length, compare it to Luna as it rises, and then again as it seems to shrink as it moves up!
Lunar Image Credit: NASA
Try using colored or Moon filters to look at the many surface features that throw amazing patterns across its surface. If you don't have moon filters, a pair of sunglasses will suffice. Look for things you might not ordinarily notice, such as the huge streak emanating from crater Menelaus, the pattern projected from Proclus, or the bright tiny dot of little-known Pytheas north of Copernicus. It's hard to miss the blinding beacon of Aristarchus! Check the southeastern limb, where the edge of Furnerius lights up the landscape, or how a nothing crater like Censorinus shines on the southeast shore of Tranquillitatis, while Dionysus echoes it on the southwest. Could you believe Manlius just north of central could be such a perfect ring, or that Anaxagoras would look like a northern polar cap? Although it might be tempting to curse the Moon for hiding the stars when it's full, there is no other world out there that we can view in such detail?even if you just look with your eyes!
Sunday, May 26 -Tonight begin your observations just as soon as the Sun sets and look to the western horizon. If you've been following the planet dance, you'll see the grand appearance of Mercury, Venus and Jupiter. They will be at their closest conjunction tomorrow night, but never waste an opportunity!
Now, let's look for an object that can be viewed unaided from a dark location and is splendid in binoculars. Just northeast of Beta Leonis you'll see a hazy patch of stars known as Melotte 111 (RA 12 22 30.29 Dec +25 50 42.0). Often called the "Queen's Hair", this five degree span of 5th to 10th magnitude stars is wonderfully rich and colorful. As legend has it, Queen Berenice of the Ptolemaic dynasty in Egypt, promised her beautiful long tresses to the gods in return for the King's safe return from battle. Touched by her love, the gods took Berenice's sacrifice and immortalized it in the stars.
One Degree Field of Melotte 111. Credit: Palomar Observatory Courtesy of Caltech
The cluster is best seen through binoculars because of its sheer size, but you'll find other things of interest there as well. Residing about 260 light-years away, this collection is one of the nearest of all star clusters, including the Pleiades and the Ursa Major moving group. Although Melotte 111 is more than 400 million years old, it contains no giant stars, but its brightest members have just begun their evolution. Unlike the Pleiades, The Queen's Hair contains no red dwarfs, and a low stellar concentration leads astronomers to believe it is slowly dispersing. Like many clusters, it contains double stars?most of which are spectroscopic. For binoculars, it is possible to split star 17, but it will require very steady hands.
Until next week... Ask for the Moon, but keep on reaching for the stars!
Attending a Star Party this weekend? Come back and tell us what you saw in the comment section below!
Tammy Plotner is a professional astronomy author, President Emeritus of Warren Rupp Observatory and retired Astronomical League Executive Secretary. She's received a vast number of astronomy achievement and observing awards, including the Great Lakes Astronomy Achievement Award, RG Wright Service Award and the first woman astronomer to achieve Comet Hunter's Gold Status.