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Tonight

How often do we have a Blue Moon in July?

Image credit: Tim Geers

Image by Flickr user Tim Geers

How often do we have a Blue Moon in July? For the answer, you have to look to a concept from astronomy and calendar studies, at what’s called the Metonic cycle.

Blue Moon – second July full moon – on July 31

Patrick Casaert – whose community on Facebook is called La Lune The Moon – used a blue filter to capture this shot of the moon on July 27, 2015.

Patrick Casaert used a blue filter to capture this shot of the moon on July 27, 2015.

Blue Moon coming! As seen in the photo above by Patrick Casaert, the moon has been waxing to full this week. Patrick used a blue filter to create his moon photo, and if you see the moon in tonight’s sky, you’ll see it’s nearly full … but not at all blue in color. Yet, as the second full moon for the month of July, many will call it a Blue Moon.

Orion the Hunter: Ghost of summer dawn

In late July and early August, watch for the three medium-bright

In late July and early August, watch for the three medium-bright “Belt” stars of Orion the Hunter to ascend over your eastern horizon shortly before dawn.

Orion the Hunter appears each Northern Hemisphere winter as a mighty constellation arcing across the south during the evening hours. But, before dawn in late July and early August, you can spot Orion in the east. Thus Orion has been called “the ghost of the shimmering summer dawn.” The Hunter rises on his side, with his three Belt stars – Mintaka, Alnitak and Alnilam – pointing straight up.

Delta Aquarid meteors peaking in moonlight

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The Great Square of Pegasus can point you to the constellation Aquarius and to the radiant point of the Delta Aquarid meteor shower.

In a dark, moonless night sky in late July and early August, you can see up to 15 to 20 Delta Aquarid meteors per hour. In 2015, the moon is in the way. Get ready, though. The Delta Aquarids will still be flying at the peak of this year’s Perseid meteor shower, which will be mostly moon-free!

Star of the week: The Double Double star

Via daviddarling.info

Via daviddarling.info

What’s a Double Double star? Ordinary binoculars show you Epsilon Lyrae as two stars in one. But look more closely. A telescope reveals that each of the two stars in the Epsilon Lyrae system is, in itself, a double star. That’s why Epsilon Lyrae is famous for being the Double Double star, a single point of light to the eye that’s really four stars in one. One stellar pair circles around the other stellar pair in an intricate gravitational dance.

Moon near Scorpion’s stinger on July 27

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The moon is to the north of the constellation Scorpius the Scorpion tonight. You can pick out two stars near the moon – in the Tail of the Scorpion – are called Shaula and Lesath. Together, these two represent the Scorpion’s Stinger. Shaula is some 350 light-years away and Lesath is about 500 light-years away

Next Blue Moon is July 31

Beautiful image by our friend Jv Noriega. Thank you, Jv! Does a Blue Moon look blue like this? No. This photo was made using special filters to create the blue color.

The moon was full on July 2, and it’ll be full again on July 31. The second of two full moons in a calendar month is often called a Blue Moon.

Moon north of star Antares on July 26

You may have difficulty visualizing the J-shaped Scorpion in the glaring moonlight, but you should be able to see the star Antares and the planet Saturn.

You might have difficulty visualizing the J-shaped Scorpion in the glaring moonlight tonight, but you should be able to see the star Antares and the planet Saturn.

Tonight – July 26, 2015 – the southernmost constellation of the Zodiac – Scorpius the Scorpion – lurks low in the evening sky. You can locate the Scorpion because the moon is moving through this part of the sky. You’ll find star Antares, the brightest star in the constellation Scorpius the Scorpion, and the planet Saturn, near the July 26 waxing gibbous moon.

Moon nearest Saturn on July 25

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Tonight – July 25, 2015 – the moon shines closest for this month to the planet Saturn. If you’ve been watching over several nights, you know that this moon is in a more easterly location than it was on July 24. Of course it is! The moon moves continually toward the east in its orbit around Earth.

Everything you need to know: Delta Aquarid meteor shower

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Late July 2015 presents the extended peak of the Delta Aquarid meteor shower – though under the glaring night of the almost-full moon. The best viewing hours are after midnight and before dawn, centered around 2 a.m. (3 a.m. daylight-saving time) for all time zones around the world. This long and rambling shower is officially active from about July 12 to August 23 each year, so you may be better off to wait for a couple weeks – or when the moonlight is much less obtrusive. This shower overlaps with the more famous Perseid meteor shower in August. Those who observe the Perseids are likely to see some Delta Aquarid meteors in the mix. Follow the links inside to learn more.