Astronomy: The Week Ahead – Sun 30 Aug to Sat 05 Sep 2015

AstroTitlePhoto Aug 30

Sunday August 30

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The Moon will rise in perigee tonight, due east. This is the Moon’s closest point to us in its monthly orbit. But look to Libra in the southwest. Saturn in a telescope is a great sight. The ringed planet is leaving us until next season, and will soon disappear into the glare of sunset. While you can, also compare the color of Scorpius’ star Antares.

Monday August 31

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Tonight Neptune is at opposition. The Earth lies directly between Neptune and the Sun. That means Neptune rises at sunset, is in the sky all night, and sets with sunrise. This is the best time to view the distant world! Here you can see it low in Aquarius, and how to use two of the constellation’s stars to point to it. Neptune is at magnitude 7.8, and can be seen in binoculars, but it is much easier to recognize its blue tone with a telescope. It is only 2.4 arcseconds in size, and with high power will appear a small bluish disk. The planet is its closest to us tonight, at almost 29 AU (astronomical units; 1 AU is the distance from the Earth to the Sun).

Tuesday September 01

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Venus is at its longest western elongation today, at 25 degrees from the Sun. Find it in the predawn sky in Cancer, near the head of Hydra, and below Gemini the twins. That red “star” nearby is Mars. Venus is inside our orbit just over 30 million miles away, and shows a very generous 51 arcseconds in size, as a 10% illuminated crescent. If you can view it through a telescope, you’ll be in for a visual treat! Mars is outside our orbit 150,000 million miles away, showing only a 3.7 arcsecond size disk. You can imagine a point during the year when the earth would be between the two!

Wednesday September 02

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Here’s a challenge for those viewing through telescopes in somewhat dark evening skies. NGC globular clusters 7006 and 6934 lie in the constellation Delphinus, roughly between Altair in Aquila, and Enif in Pegasus. Both are small, at 3.6 and 7.1 arcminutes, respectively. They shine at magnitudes 10.6 and 8.9. Both will be unresolved, you can’t see individual stars in them. So, they will both appear as somewhat granular, fuzzy glows.

Thursday September 03

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Lying between the paws of the Great Bear, Ursa Major, and the twins of Gemini, is the dim constellation Lynx, the cat. It has only one star brighter than magnitude 4.5, Alpha Lyncis, at magnitude 3.12 and 223 light years distant. It is a supergiant star, at 118 solar radii, and has the luminosity of 1622 suns!

There are only four main stars in the constellation, and they seem to get dimmer as you progress from Alpha. Can you make out the figure? This area has many dim open clusters and one famous globular cluster, which we’ll discuss Saturday.

Friday September 04

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How far can you see with the “naked eye”? Try for M31, the Great Andromeda Galaxy. Distance estimates range from 2.3 to 2.9 million light years. It will appear as a dim fuzzy patch, a short hop above the orange star Beta Andromedae. Find the sweep of the constellation Andromeda between the famous ‘W’ of Cassiopeia, and the Great Square of Pegasus. Once you identify the two arc comprising Andromeda, jump up from the star Beta, to dimmer star just above it, the up again about the same distance. Do you see the dim elongated glow? If so, grab some binoculars and try again.

Saturday September 05

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Here’s another challenge object. NGC 2419 is a globular cluster in the constellation Lynx. It measures a bit over 2 arcminutes in size and shines dimly at magnitude 10.4. It appears unresolved in most amateur telescopes, but will break up into individual stars at high power in larger telescopes. Thought to be 200,000 light years from Earth, it is the farthest such object in our galaxy. Most globular clusters in our galaxy are less than 1/3 that distance. Speculation exists that it was captured from another passing galaxy, and has been named “Intergalactic Wanderer.”

Happy viewing!

Crash

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Astronomy: The Week Ahead – Sun 2 Aug to Sat 8 Aug 2015

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Sunday August 2

The Moon attains perigee at 03:11 today, its closest point to Earth during this lunar month. In a waning gibbous phase it is nearly 18 days old with 89% illumination. You can watch it rise just before 10 p.m. in Aquarius over the eastern horizon.

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Monday August 3

The eastern morning sky an hour before sunrise features many familiar winter constellations. And today the planet Mars wanders in among them, shining red low on the horizon. Can you find it before dawn washes it out? If you do, compare its color to the giant red stars Aldebaran in Taurus, and Betelgeuse in Orion.

Mars is in Gemini, shining at a bright magnitude 1.70, around 239 million miles from us.

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Tuesday August 4

Get your binoculars out and look due south above the stinger of Scorpius tonight, to find Messier 6 (M6), The Butterfly Cluster. This open cluster is visible without optical aid from even reasonably dark locations, at a bright magnitude 4.2. It is 33 arcminutes in size, comparable to the angular size of the full Moon. At 1,600 light years distance, imagine how brilliant these young stars would be were they the distance of some of our brightest neighbors in the sky! Although their discovery is officially attributed to Giovanni Battista Hodierna in 1654, it is very reasonable to believe Ptolemy saw it, and its neighbor M7 (The Ptolemy Cluster) in the First century.

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Wednesday August 5

After Pisces has risen, look for the waning gibbous Moon, then, with binoculars, less than two degrees away you’ll find the green-toned planet Uranus at magnitude 5.8 very nearby the magnitude 5.1 star Zeta Piscium. The Moon is 384,399 km distant, Uranus 1.8 billion miles from us, and Zeta 148 light years away. Zeta is an optical double star (not a binary), with its components 23 arcseconds apart.

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Thursday August 6

Tonight is last quarter Moon, rising after midnight at 00:26. It is a good weekday night for deep-sky observing, and if not for the Moon we’d be looking for the Southern Iota Aquariid Meteor Shower. If you still want to try for some meteors, here is the radiant, where this shower will appear to emanate from. Expect 7-8 meteors an hour, averaging magnitude 3.

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Friday August 7

The constellation name Lacerta is Latin for Lizard. This is a small and faint constellation created by Polish astronomer Johannes Hevelius in 1687. You’ll find it along the Milky Way between the W of Cassiopeia and Cygnus (the northern cross). Its brightest star, Alpha Lacertae, is a dim magnitude 3.76, so this constellation is a challenge to discern. See if you make out its zigzag shape.

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Saturday August 8

Located between Cor Caroli in Canes Venatici, and Arcturus in Bootes, M3 is a bright and easy globular cluster to see in binoculars and any telescope. Arcturus is found by taking the handle of the Big Dipper and making an “arc to Arcturus”. Similarly, you can use the dipper’s handle to make a right angle to Cor Caroli. The cluster will be visible easily in binoculars or a finderscope, slightly closer to Arcturus than the halfway point to Cor Caroli. M3 is 16 arcminutes in size, large for the northern hemisphere, and shines at magnitude 6.19 at a distance of 33,000 light years. This is an impressive cluster of over 500,000 stars!

Happy viewing!

Crash

Astronomy: The Week Ahead – Mon 20 Apr to Sat 25 Apr

This Wide Field Camera 3 image, dubbed "Mystic Mountain", was released in 2010 to commemorate Hubble's 20th anniversary in space.

This Wide Field Camera 3 image, dubbed “Mystic Mountain”, was released in 2010 to commemorate Hubble’s 20th anniversary in space.

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Monday April 20

M22 is a huge globular cluster visible without optical aid in dark skies. It is a bright fuzzy patch in binoculars, and a grand sight in any telescope, although with an 8″ or larger, you will resolve hundreds of its stars. At 10,600 light years it is one of the nearest globulars. It is one of four globulars known to contain a planetary nebula.

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Tuesday April 21

The realm of the galaxies is now rising in the east after sunset. You’ll find the area between Virgo’s bright star Spica, Denebola in Leo, and Arcturus in Bootes.

The heart of the Virgo Galaxy Cluster lies predominantly in and above the arc of stars higher in Virgo, above Porrima. If you learn to recognize Virgo’s shape, you’ll have many enjoyable observing sessions viewing dozens of galaxies in this area. In fact, they are so plentiful that you will find yourself not star hopping, but “galaxy hopping.”

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Wednesday April 22

Return tonight to Virgo in the east. Use your telescope to look for the classic edge-on spiral galaxy M104. A good star-hop is to use nearby Corvus to cut diagonally across the sail shape, then beyond about half the same distance. Move the telescope up slightly at a right angle and look for a slash-type shape in the eyepiece. Add magnification to observe the dark lane and its small bright core.

M104 is part of the Virgo Cluster of galaxies, about 28 million light years away. M104 is about one third the size of our Milky Way.

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Thursday April 23

The Lyrid Meteor Shower reaches its climax tonight. The best time to watch is from midnight on.

The Lyrids are a remnant of Comet Thatcher (C/1861 G1) in its 415-year orbit of our Sun. Without a Moon to brighten tonight’s sky during the meteor shower, prospects are good to see 10 to 20 meteors per hour.

Dress warm, have a thermos of hot chocolate, sit in a comfortable chair, and watch toward the radiant, shown here in the northeast, near Lyra’s bright star Vega.

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Friday April 24

Mizar is a famous multiple-star system in the equally famous Big Dipper of Ursa Major, which is currently directly over our north star Polaris an hour after sunset.

Mizar and its brightest companion, Alcor, can be seen as a naked-eye pair. Native American tribes used the pair as an eye test, to distinguish who could be a hunter, with keen eyes, and who could not.

The system is actually a quadruple star. Mizar shines at magnitude 2.23, Alcor at 3.99, lying 83 light years away from Earth. They are a lovely sight in any telescope!

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Saturday April 25

Tonight is the First Quarter Moon is in the constellation Cancer, and will be bright enough to overwhelm any of the constellations stars. It will form a very pretty pair with Jupiter, a bit higher up, also in Cancer. Lower toward the western horizon, Venus will be very bright. Mercury is just hidden behind the hills of the western horizon and will start popping up tomorrow. Watch for Mercury to pair with the Pleiades skimming the horizon on the evening of May 1.

Happy viewing!

Crash

Astronomy: The Week Ahead – Mon 23 Mar to Sat 28 Mar 2015

the week ahead

Charts and Jupiter image from Starry Night Pro; M11 cluster image courtesy NOAO. M27 and NGC 2169 images courtesy Wikipedia Commons; additional graphics created in Adobe Illustrator CS6.

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Monday March 23

The western sky is graced tonight as twilight dims, by a fine view of Venus, Mars and the Pleiades in an almost vertical line. Mars will be very low on the horizon in Pisces, as it continues to leave for the season. Venus, between Cetus and Aries is a beacon, easily outshining anything else. The Pleiades sits between the bright stars Aldebaran in Taurus and Mirfak, which joins the two star chains in Perseus.

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Tuesday March 24

Tonight’s 5-day-old waxing crescent Moon is squarely in the Hyades open star cluster of Taurus, and under three degrees from Aldebaran. It will be a great sight so close to the red star. Framing the pair will be Orion, its two first magnitude stars and bright belt, and opposite them the Pleiades cluster completes this celestial assemblage. The moon, ever changing, provides a focus for naked-eye astronomy.

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Wednesday March 25

Cepheus is up in the northeast before sunrise, and can be found between the recognizable W shape of Cassiopeia, Polaris in Ursa Minor, and Cygnus’ brightest star Deneb. Two shapes are distinct in this constellation, a square, with a triangle attached to one side.

Cepheus is one of the Greek astronomy Ptolemy’s original 48 constellations. Being along the Milky Way, it is rich in open clusters and nebulae. It is also home to quasar S5 0014+81, containing a 40 billion solar mass black hole. The most massive black hole known.

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Thursday March 26

The ecliptic is an imaginary line (shown here in green) along the plane of our solar system. It is easy to imagine early this evening as the sky darkens, with Mars, Venus and Jupiter located almost directly on it. The Moon also follows the ecliptic, but look at how far off it is compared to the planets.

The Moon varies more from the ecliptic than the visible planets. It can occult Aldebaran and other bright stars near the ecliptic.

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Friday March 27

Want to see summer approaching just a week into spring? Here is some morning magnificence, the summer constellation Scorpius and the Teapot of Sagittarius, due south just an hour prior to sunrise today. Through the two pass the brightest part of our home galaxy the Milky Way, dense with stars, clusters and dark nebulae. Grab a pair of binoculars and sweep this area, you’ll be amazed. For added fun, compare the colors of Saturn and Antares.

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Saturday March 28

M27 is a very bright and large planetary nebula known as the Dumbbell, for its visual shape. It is a snap to locate using three stars in Cygnus and imagining where a fourth one would create a rectangular shape. You can see it as a roundish glow in binoculars, and pick up the dumbbell or apple-core shape in a telescope. Using a narrowband filter will bring out more detail. It is a great target for a quick morning view.

This is the brightest planetary nebula, and the first discovered, by Charles Messier in 1764.

Happy viewing!

Crash

Astronomy: The Week Ahead – Sun 08 Mar to Sat 14 Mar 2015

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Sunday March 8

Due south at sunset is the constellation Canis Major and its brightest star Sirius. Sirius is the brightest star in the night sky at magnitude -1.5 and is a double star, a binary star system. The companion, Sirius B, is a white dwarf star, shining at magnitude 8.5. The brightness of the primary can make seeing the companion difficult, but you can do it in a telescope. Its separation from Sirius A changes around every 50 years, and it is now approaching its widest separation. Read up on Sirius, you’ll be amazed at what you learn, it’s a very interesting star!

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Monday March 9

The constellation Scorpius is one of the twelve Zodiac constellations, lying along the ecliptic. The Moon and planets all traverse this constellation in their paths across the sky. Seen as a scorpion in ancient times, the constellation Libra represented its claws in Babylonian times. Antares is the red beating heart.

Scorpius is beautifully positioned due south currently for northerners, in the predawn skies.

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Tuesday March 10

Get your telescope or binoculars out this morning for a view of two globular clusters just off Antares in Scorpius. M4 resolves into hundreds of stars in a telescope. It is about 7900 light years distant and very bright at magnitude 5.9, and visually about the size of our full Moon. Nearby, almost in the glow of Antares is NGC 6144, a 4.9′ magnitude 9 glow that will not resolve into individual stars. This smaller, dimmer globular is located 33,000 light years away. Nice contrast between this two similar objects!

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Wednesday March 11

NGC 2903 is sometimes referred to as the “forgotten Messier.” It is certainly bright and big enough to warrant inclusion in the famous catalog. And it is easy to locate off the “tip of the nose” in Leo. Easiest is to use Regulus to move up the Sickle, then extend beyond it to the nearest bright star, and drop down slightly. At magnitude 9.7 and a generous size of 12.6’x6.0′, this galaxy discovered by Sir William Herschel is a great target.

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Thursday March 12

An hour before sunrise the Moon and Saturn are paired three degrees apart high up in Scorpius. The soft creamy yellow glow of Saturn will be very apparent contrasted against the whiteness of 21 day old waxing gibbous moon, 62% illuminated.

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Friday March 13

The last quarter Moon occurs today, and will be located in Ophiuchus an hour before sunrise. The position of the moon allows us to see the “bottom line” of Ophiuchus easily, as two pair of stars, one pair wide, and the other close. Another pair extends west into Serpens Caput.

A last quarter Moon on a weekend is especially nice, as it rises late, affording us plenty of dark sky time to observe dim targets such as galaxies and nebulae. Lucky us, on this Friday the 13th!

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Saturday March 14

Revisit Canis Major this evening, for a look at two interesting open clusters. M41 is a large and classic open cluster you’ll see in binoculars. This cluster is thought to have been known by Aristotle, around 325 B.C. It is a bit larger than a full Moon, and bright enough to be seen naked-eye at magnitude 4.5. NGC 2362 will require a telescope. It is stunning, with the extremely large and luminous star Tau Canis Majoris at its center. A fun trick of the eye is to tap your telescope when viewing, and watch Tau jump around while the other stars seem almost stationary!

Happy viewing!

Crash

Astronomy: The Week Ahead – Mon 23 Feb thru Sat 28 Feb

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Monday February 23

Today Saturn is at western quadrature. The earth and Saturn are at a 90-degree angle from each other relative to the Sun. Quadrature occurs at 5:38 A.M. PST.

Saturn will culminate (reach its highest point above the horizon) at sunrise today. This means Saturn is visible in the night sky for almost half the dark hours, rising at 01:05 and fading into the sunrise which occurs at 06:47.

As the Earth catches up in our orbit, Saturn will be visible in the night sky during more dark hours.

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Tuesday February 24

Crash Test: Have you been watching the Venus and Mars show the last several days? Mars was just above Venus last week, and has now moved below. Which planet is moving faster across our sky?

The two are just under 1 and 1/2 degrees apart from our viewpoint, but separated by 0.815 AU (Astronomical Units) in actual distance. An AU is the measure of the Earth’s average distance from the sun, approximately 93 million miles.

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Wednesday February 25

Today’s first quarter Moon is 1 degree north of the giant red star Aldebaran, in Taurus. They form a striking pair set above the giant Orion, and its bright stars Betelgeuse and Rigel. Early in the evening, you can also see Jupiter to the east and the pair of Venus and Mars to the west.

Today also marks Neptune’s conjunction. It is on the opposite side of the sun from the earth.

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Thursday February 26

Everyone loves a two-for-one deal, and here’s one to start your day with.

The constellation Hercules is up in the east before sunrise. You can make out its shape above the bright star Vega (in Lyra). It contains two great globular clusters, M13 and M92. They are easy to find in binoculars using the “keystone” shape of Hercules’ body. M13 is 2/3rd along one side of the keystone. Using the other side of the keystone, hop twice that distance to a star, then go about 1/3rd the way back toward the top star in the keystone. Both giant globular clusters are about 25,000 light years distant.

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Friday February 27

The summer constellation Scorpius is up nicely in the morning skies. Saturn is in the same field of view as the multiple star Nu Scorpii. Antares burns red as the heart of the scorpion. The stinger is easy to imagine as the stars Shaula and Lesath.

Nearby are the binocular objects M6 and M7, two lovely bright open clusters in the heart of the Milky Way.

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Saturday February 28

The Moon now dominates the evening sky, growing in waxing gibbous phase and 82% illuminated tonight. Its brightness will obliterate our view of the winter Milky Way running between Orion and Gemini. Only the brightest stars and Jupiter will be visible in the nearby constellations. Look for Procyon in Canis Minor – it shines at magnitude 0.37. Can you spot it with a bright moon so nearby?

Happy viewing!

Crash

Astronomy: The Week Ahead

Celestial events from Sunday, February 15th to Saturday, February 21st

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Sunday February 15

M78 is a nice bright reflection nebula in Orion, easy to locate using the Belt Stars.

From suburban skies, you will be able to detect a glow. From dark skies though there are several nearby NGC sections visible as well forming a chain running along one side of this Messier object.

M78 is 8.7’x7.8′ in size and shines at magnitude 8.3, and belongs to the Orion Molecular Cloud Complex, about 1,600 light years from earth. It was discovered by Pierre Méchain in 1780.

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Monday February 16

Look to the west before sunrise this morning and see Jupiter about to set. Since it is close to opposition, the giant planet is in the night sky all night long.

Jupiter is nearly on the ecliptic, the green line in the image, representing the plane of our solar system. Note the bright stars Regulus in Leo and Spica in Virgo are very close to the ecliptic. Because the planets and Moon move along the ecliptic, varying a bit above and below it, we can see them occult these bright stars.

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Tuesday February 17

How about a quick Crash Test? Note the band of the winter Milky Way standing almost straight up from the southeastern horizon after sunset. Many bright stars are found along and near the Milky Way. Here are several with a question mark by them – so what are they?

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Wednesday February 18

There are 88 modern constellations in the sky, some dating back to ancient times.

Within the constellations, there are other shapes within constellations that have gained popularity. These are called asterisms. For example, most people looking at Ursa Major don’t see the constellation shape, but instead see the Big Dipper.

Here are a few other asterisms visible this morning. The Sail in Corvus, The Kite in Bootes, The Sickle in Leo, the Diamond of Virgo.

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Thursday February 19

Try hunting down Messier 77 tonight high in Cetus. This is the brightest of the Seyfert Galaxies, which containing quasars.

M77 is a barred spiral, 47 million light years from us. Discovered by Pierre Méchain in 1780, you will see the bright inner core of the galaxy in amateur telescopes. On a very good night, it is possible to detect the tightly wound spiral arms around its core. At magnitude 9.6 and 7.1’x6.0′ in size, it is visible from suburban skies.

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Friday February 20

Tonight make sure to look to the west and see this great conjunction of Venus, Mars and a very young Moon!

Venus will be easy to pick out as the sky is darkening. Shining -3.95, it will be the brightest object in the sky after sunset. Mars will appear much dinner at magnitude 1.26 and only 0’40” away from Venus. See if you can detect the color differences. Just over a degree away from Mars a very thin 2.4-day-old Moon will show its waxing gibbous crescent, with only 6% of its disk illuminated.

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Saturday February 21

M76 is called the Little Dumbbell, and as the photo shows, is obvious in its bi-lobed shape. Find it at the ends of Andromeda and Perseus.

This is a planetary nebula, a star in its death throes, expelling its outer shells of atmosphere. At the core the dying star is radiating in oxygen 3, so it is a type of emission nebula. A narrow band filter will dim out the background and allow through the specific wavelength of light this object emits, so you will be able to see it in greater detail.

Happy viewing!

Crash

Astronomy: The Week Ahead – Sun 26 Jan to Sat 31 Jan

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Sunday January 25

Here is a view of tonight at 8 p.m. via PST. The Moon is between the constellations Gemini and Cancer. Notice the two circles, one inside the other, near the center of Cancer. If you know what they are then you’ll also know they are always present, can be seen visually, and are constantly in motion.

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Monday January 26

Today the Moon reaches its First Quarter phase. Moon phases begin at New Moon, when the Moon is too close to the Sun to be viewed. The lunar month begins with waxing crescent, waxing meaning getting (visually) larger. Today it changes from crescent to gibbous; over half the Moon illuminated by the Sun. After Full Moon, it begins waning, and is less illuminated each night. The waning gibbous Moon changes to a waning crescent as it passes through Third Quarter, as it continues on toward the next New Moon.

Also, on Monday evening January 26th, it will become the largest asteroid to pass closest to Earth until 2027 when 1999 AN10 will approach within one lunar distance. (See:  Astronomy: Big Asteroid 2004 BL86 Buzzes Earth on Monday 26 January)

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Tuesday January 27

Morning observers can find the Sunflower Galaxy, M63 high in the northwest, in the constellation Canes Venatici, the Hunting Dogs. Using the constellation’s one bright star, Cor Caroli (The Heart of Charles), and the end star of The Big Dipper as reference points, it is easy to star hop to.

The galaxy is bright at magnitude 8.6, and will be visible from darker locations in binoculars and any telescope. It will appear elongated and containing a bright core. It is part of the same galaxy group at M51, The Whirlpool Galaxy, and at a distance of about 35 million light years.

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Wednesday January 28

This morning before sunrise look for the constellation Serpens Caput in the southwestern skies. It will be directly above Saturn. An easy way to find it is along the line of stars the define the lower part of Ophiuchus, as they point to Serpens Caput’s brightest star, Unukalhai, which is a double star. The name Unukalhai translates from Arabic as “The neck of the serpent”. It is also called Cor Serpentis, the heart of the serpent.

Serpens is broken into two parts, on opposite sides of Ophiuchus, the Serpent Bearer in Greek mythology. Caput is on the western side and Cauda to the east.

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Thursday January 29

An hour after sunset you can see Jupiter rising near the eastern horizon, and a bright waxing gibbous Moon in Taurus near Aldebaran. Note the green line crossing upward from near Jupiter. It is the ecliptic, the path of the sun through our skies. Constellations along the ecliptic are the signs of the Zodiac.

The Moon and planets follow the ecliptic, but wander north and south of the sun’s path. The Moon tonight is south of the ecliptics, Jupiter slightly to its north.

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Friday January 30

With a large bright Moon in the sky, near Orion and Gemini, let’s look away, to the north for a nice bright target.

M103 is a beautiful small jewel of an open star cluster, in Cassiopeia. Even binoculars will reveal its three brightst stars, magnitudes 7 and 8, in an almost straight line, with hints of nebulosity. Overall, it is bright (magnitude 7.4) and small, occupying only 6 arc-minutes, and rich. One experienced observer counted 28 stars in the cluster in a 13″ telescope, noting a nice chain of of 10th magnitude stars along its northeast side.

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Saturday January 31

Tonight Jupiter treats us to two very good shadow transits, with interesting timing! Start by finding the Great Red Spot near meridian at 22:26 PST. Two minutes later Io’s shadow begins ingress on Jupiter’s disk. The Moon itself will ingress ten minutes later. Io’s shadow will end its transit at 00:45, and Io at 00:56. In another seven minutes you’ll see Europa’s shadow transit begin.

Happy viewing!

Crash

Astronomy: Nov 5th – 8th Night Skies

Check out the night skies this week!

Monday, November 3
As autumn proceeds, the Great Square of Pegasus looms ever higher at nightfall. It now reaches its level position very high toward the south as early as 8 or 9 p.m. this week — with the Moon shining under its left side tonight (for North America).

Tuesday, November 4
As the stars come out, look high above the waxing gibbous Moon for the Great Square of Pegasus. It’s standing on one corner.

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Wednesday, November 5
Algol is at minimum light for a couple hours centered on 6:56 p.m. EST.

Thursday, November 6
Full Moon (exactly full at 5:23 p.m. Eastern Standard Time). The Moon shines far below the two or three brightest stars of Aries during the evening. Can you see the Pleiades through the moonlight? The delicate little cluster is well to the Moon’s left.

Friday, November 7
The Moon, just past full, rises in the east at dusk. Once it climbs high, look for orange Aldebaran to its lower left and the Pleiades to its upper left.

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Saturday, November 8
The waning gibbous Moon rises around the end of twilight. Look for Aldebaran not very far to its upper left. Higher above Aldebaran are the Pleiades.

Happy viewing!

Crash

Astronomy: Harvest Moon Rises Monday in Summer ‘Supermoon’ Finale

Deer graze in the foreground of this 2013 image of the full Harvest Moon

Deer graze in the foreground of this 2013 image of the full Harvest Moon

The full Harvest Moon will light up the night sky on Monday (Sept. 8), and this year it comes with an extra bounty. September’s full moon will cap a trio of back-to-back “supermoons” for the Northern Hemisphere summer, according to NASA. 

The moon will reach its full phase when it reaches the spot in the sky opposite from the sun. That moment will occur Monday at 9:38 p.m. EDT (0138 GMT). Monday’s full moon is the one nearest to the September equinox this year, giving it the moniker of Harvest Moon by the usual definition.

Although we associate the Harvest Moon with autumn, this year’s version is actually the last full moon of the summer season. The 2014 Harvest Moon comes about as early in the calendar as possible. However, Harvest Moons can occur as late as Oct. 7th.

Times of moonrise for 10 North American cities on three nights in Sept. 2014.

Times of moonrise for 10 North American cities on three nights in Sept. 2014.

Although on average, an October Harvest Moon happens once about every four years, this figure can be deceptive. The last October Harvest Moon, for example, was in 2009, but the next won’t occur until 2017. Conversely, after 2017, we need wait only three years until 2020 for the next October Harvest Moon.

This full moon also marks the third in a trilogy of “supermoons” this summer. July and August’s full moons both fell during the moon’s perigee — when it was at the closest point in its orbit to Earth. While the August supermoon was the closest, this month’s full moon also falls during perigee.

Many think that the Harvest Moon remains in the night sky longer than any of the other full moons we see during the year, but that is a myth. The Harvest Moon’s claim to fame is that instead of rising its normal average of 50 minutes later each day, it rises only a little later each night, providing farmers with extra moonlit evenings to reap their crops.

This unusually small daily lag in the time of moonrise occurs because the moon is traveling along the part of the ecliptic — the apparent path of the sun with respect to Earth’s sky — that makes the smallest angle with the eastern horizon as seen from northern latitudes.

Through the course of three nights — Sept. 7 to Sept. 9 — the rising of the moon comes just under 38 minutes later each night, based on an average taken from a small sample of North American cities. The night-to-night difference in moonrise times is greatest for the more southerly locations. (Miami, for instance, sees moonrise come an average of 46 minutes later in the three-night sample).

Great Harvest Moon of the North

The Harvest Moon effect is greater the farther north an observer is located.

In contrast, for those living in the Southern Hemisphere, the ecliptic at this time of year appears almost perpendicular (at nearly a right angle) to the eastern horizon. As such, the difference for the time of moonrise exceeds the average of 50 minutes per night. In Sydney, Australia, for instance, the night-to-night difference amounts to 70 minutes.

For those who live near the Arctic Circle, however, the moon does indeed appear to rise about the same time each night around the time of the Harvest Moon. And for those who live even farther to the north, a paradox: The moon appears to rise earlier, not later.

In Thule, Greenland (latitude 76.5 degrees north), for example, the times of moonrise on Sept. 7, 8 and 9 will be, respectively, 7:19 p.m., 7:06 p.m. and 6:54 p.m. local time. So from Thule, the moon will seem to rise an average of 13 minutes earlier each night.

I’ll be out with my camera and hope you will be too. I’m looking forward to seeing your pictures!

Happy viewing!

Crash