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August 2015 Urban Observing August 1, 2015

Posted by aquillam in Astronomy.
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Special Events

Meteor Showers

August is known as the month of meteor showers. The Perseids and the best known and the best shower in August, and should peak on the 13th this year. That means you should observe sometime between midnight and 5 AM on the morning of the 13th and/or 14th. There are a few other meteor showers too, but they aren’t as big, so I think I’ll leave that for another post so I can get this one finished before the 1st!

Moon

Full Aug 29 18:38 UT (2:38 EDT).
The Moon is at perigee about 20 hours latter, at 15:22 UTC (11:22 EDT), making this a supermoon.
Being late summer, it’ll be higher in the sky than the last few full moons, so it’ll be even more problematic for deep sky observers. According to the Old Farmer’s Almanac, the August moon is the Sturgeon or Green Corn Moon.

Planets

Mercury

Mercury peeks out of the evening twilight this month. on the fist it sets 35 minutes after the Sun so you’ll have to work to find it. By mid month it’ll hang out nearly an hour after the Sun sets. It reaches aphelion on August 29, and greatest eastern elongation on Sept. 3, so it really doesn’t get farther from the Sun than this! It’s still a tiny planet in twilight though, so binoculars or a small ’scope are very helpful. Look for a Jupiter-Mercury conjunction on August 6, and for Mercury with a young crescent Moon on the 16th.

The Moon and Mercury in the evening twilight

The Moon and Mercury on August 16 at dusk

Mercury and Jupiter in twilight

9 pm on August 6, 2015

Venus

Venus reaches Inferior conjunction on August 15, so it’s not visible most of the month. If you happen to be up before 6:30 though, start looking for it in the east beginning around August 21. It zips past Mars at the end of the month / early September.
Venus and Mars just before dawn on August 31

Venus and Mars just before dawn on August 31

Mars

Mars is for morning observers this month. A very old Moon will be near it on August 12, but it’ll be tough to spot without binoculars. It crosses M44 on Aug 19, but you’ll need a ‘scope to pull the cluster out of the twilight.

Mars and the Moon near Gemini

Mars and the Moon pair up in the pre-dawn sky on August 12

Jupiter

Jupiter disappears quickly into the twilight this month, reaching conjunction on August 26. Before it disappears, catch it pass half a degree from Regulus on August 8 – 11
Mercury, Regulus, and Jupiter in twilight

Jupiter and Regulus are less than a degree apart on August 8, 2015.

Saturn

Saturn continues to drift slowly from Libra to Sagittarius this month. Look for it with a first quarter Moon on August 22.
The Moon and Saturn near Scorpio

The Moon passes Saturn

Neptune

Opposition is at roughly 03:00 UT September 1, which is about 11 PM Aug. 31 here. That means Neptune is closer the Earth at the end of this month and beginning of September than at any other time this year, so it’s your best chance to see it as something more than a faint dot. There isn’t much around it to guide you though, so you’ll probably want some more detailed maps than I can post here, or (of course) a computerized ‘scope.
Neptune on August 31

Neptune on August 31

Deep Sky

Double Stars

The nice thing about stars is that they are point sources. You just look at the magnitude and you pretty much know whether or not you’ll be able to see it. However, stars don’t look too much different though the ‘scope than naked eye, so they aren’t the most exciting things to look at. Unless it’s not just 1 star…
The easiest double is Alcor & Mizar. It’s a naked eye double in the handle of the Big Dipper. A telescope reveals Mizar as a double, and a fourth star in the system.
Albireo is also fairly easy to find, at the head of Cygnus. A telescope reveals it as a yellowish star and a blueish star (though different people will see the colors differently.) Nearby, you can test the resolution of your ‘scope on Epsilon Lyrae, the double-double. A small ‘scope separates it into two stars, which each resolve as two stars in a bigger ‘scope..

Globular star clusters

The summer skies are full of globular clusters. Three of the nicest are M13, M92, and M3. M13 and M92 are high overhead at the start of the month, one M3 is to the west. At the end of the month, M3 is low in the west and M13 and M92 are high in the west.

Open clusters

The summer Milky Way is high overhead, and of course it is full of open clusters. Two of the nicest clusters are M6 ( the butterfly cluster) and M7 (the northern jewel box). They transit at 9 PM at the end of the month, when it’s still twilight, so look for them soon!

Nebula

Bright skies make it really hard to see nebulae. M57 (the ring) is a nicely compact object, so even though it’s faint you might be able to pull it in with a small ‘scope. M27 (dumbbell) has a brighter magnitude, but it’s also bigger, so it has a lower surface brightness, which makes it much harder to see in urban skies. If you happen to have a good night, or a nebula or oxygen filter, it’s worth trying. Also worth trying is M8, the lateen nebula. Unlike M27 & M57, which are the remnants of dying Sun-like stars, M8 is a star forming region. In dark skies, M8 is visible to the naked eye as a large fuzzy patch in Sagittarius, sometimes even referred to as the steam from the tea pot. Binoculars are enough to pull out the associated star cluster and bright inner region, even under fairly bright skies. A small ‘scope might pull in some of the wider dust lanes.

Galaxies

One of the great things about August is the return of M31. Look for it low in the northeast at 10 PM at the beginning of the month, or mid height in the east-north-east at the end of the month.
15Aug2200z_map
Full sky map on August 15, 10 PM.

Full sky map on August 15, 10 PM.

July 2015 Urban Observing July 6, 2015

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
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Special Events

Aphelion

Aphelion (ap-HE-lee-on) occurs on July 6 at 19:41 UT (3:41 EDT). That’s the point in the orbit where a Earth is farthest from the Sun.

Blue Moon

The first full moon of July occurs on July 2 at 2:20 UT (that’s 11:20 on July 1 here in Ann Arbor). The second is on July 31 at 10:43 UT (or 6:43 AM EDT). The popular definition of “blue moon” is the second full moon in a month, and that makes the July 31 moon a blue moon. Another (older) definition is the third of four full moons in a season. Since summer started on June 21, the full moons of July are actually the first and second full moons of summer, and there are only 3 full moons this season.

Meteor Showers

The Delta Aquariids bring to an end the quietest months for meteor watchers. Unfortunatly, they should peak on the 28 – 29, just before the second full moon of the month. Start looking for them in the pre dawn skies about a week before that, after the Moon has set. That means looking for them between 2 – 4 AM local time from July 21 – 26. For the peak and a few days around it, your bet bet will be around 3 -5 to avoid as much moonlight as possible and the morning twilight. After the peak, the waining moon is impossible to avoid, and the Moon passes through Aquarius on August 2. The radiant will be highest around 3 – 4 AM both weeks.

Location of the Delta Aqu. radiant on July 29 at 3:42 AM in Ann Arbor.

Location of the Delta Aqu. radiant on July 29 at 3:42 AM in Ann Arbor.

Planets

Mercury

is a morning planet at the start of the month. It will be difficult to spot, but if you’re up for a challenge and have a pair of binoculars, look for Mercury, Mars, and an old Moon half an hour before sunrise on July 14. It disappears into the glare of the Sun not long after, but look for it’s return to the evening skies in August!

Mercury, Mars and the Moon align on July 14, about 20 minutes before sunrise.

Mercury, Mars and the Moon align on July 14, about 20 minutes before sunrise.

Venus

is spectacular in the west all month. A waning crescent, it is getting ever closer to us, which means bigger and brighter too. By the end of the month, you should be able to tell it’s a crescent with just a small pair of binoculars. Here are a couple images to help you compare size (both simulate a 15″ field of view.)

The appearance of Venus on July 31 in a telescope with a 15 arcminute field of view (approx.)

The appearance of Venus on July 31 in a telescope with a 15 arcminute field of view (approx.)

The appearance of Venus on July 1 in a telescope with a 15 arcminute field of view (approx)

The appearance of Venus on July 1 in a telescope with a 15 arcminute field of view (approx)

Mars

emerges from the glare of the Sun this month. It is less than half a degree from Mercury on the 16th! Unfortunately for most of us, you’ll have to be up before the Sun to see it.

Conjunction of Mercury and Mars on July 16 about 20 minutes before sunrise.

Conjunction of Mercury and Mars on July 16 about 20 minutes before sunrise.

Jupiter

After the conjunction with Venus on June 30, Jupiter works his way slowly to the east, winding up in a conjunction with Mercury and Regulus around August 6. Look for Venus, Jupiter and a young moon together on July 18.

Venus, Jupiter, the Moon, and the star Regulus on July 18 at 9:30 PM (about half an hour after sunset)

Venus, Jupiter, the Moon, and the star Regulus on July 18 at 9:30 PM (about half an hour after sunset)

Saturn

It’s a great month for observing Saturn. It is high in the south at 10 PM, but getting farther from us all the time. The quarter moon passes by it on July 25 – 26.

Saturn and the Moon on July 25 at 10 PM.

Saturn and the Moon on July 25 at 10 PM.

Deep sky

July snuck up on me, so I don’t have any deep sky stuff prepared. Maybe I’ll get a few things posted as the month progresses. In the meantime, I’ll just throw a couple things out there.  ‘Tis the season for Albireo, a maize & blue binary in Cygnus. Not far from M13, a globular cluster in Hercules, which is a naked eye object in dark skies. Compact planetary nebula M57 sits between the two stars at the bottom of the harp in Lyra. It’s smaller size helps it stand out against a pretty bright sky in a small ‘scope.

Evening Gathering April 21, 2015 April 20, 2015

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
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There’s a gathering of goodies for urban observers this week in the west.

The best night is April 21, about half an hour after sunset. Venus, the Moon and Aldebaran gather about 30º above the west horizon that night. to the right and a little lower, you’ll find the Pleiades. Grab a pair of binoculars or a small ‘scope to find Mars and Mercury, just above the WNW horizon. As long as you have those binoculars out, look over to the WSW for the Orion nebula, M42.

If you miss the evening of the 21, don’t worry. You’ll get a few more nights for everything but the Moon. And if it’s Mercury you’re after, next week will be better.

Looking west at 8:45 PM on April 21 from Ann Arbor.

Looking west at 8:45 PM on April 21 from Ann Arbor.

Urban Observing January 2015 January 1, 2015

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
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Special events

What better way to start a year then with a comet. Already a naked-eye object at the end of December, comet Lovejoy should brighten more during January, making it a good binocular target for urban skies. It starts the month in the constellation Lepus, just below Orion’s feet. It then travels up past Orion, through Taurus, Aries and Triangulum. On Feb 2, you’ll find it next to Almach, the foot of Andromeda. Look for it especially January 13-20, when you’ll have less interference from the waning moon, and the comet should be at its brightest. Also, it’s not too far from the Pleiades on those days. There’s a great map, not to mention an article with some spectacular pictures, on the Sky and Telescope website.

Comet Lovejoy near the Pleiades at 9 PM on January 17.

Comet Lovejoy near the Pleiades at 9 PM on January 17.

Some of you will enjoy knowing that perihelion, Earth’s closest position to the Sun, occurs on January 4 this year. Some of you will, of course, be confused because January is the coldest part of winter here in the northern hemisphere. Just remember, it’s the tilt and whoever gets more sunlight, not the distance that counts. After all, it’s summer down south right now!

Meteor showers

The year kicks off with what could be one of the best meteor showers of the year. Unfortunately, the Quadrantids have a very short peak, and the weather in the northern hemisphere at this time of year tends to be terrible for observing. Also, a gibbous Moon interferes this year. Still, with a typical rate of 25 meteors per hour bright enough to see in the glare of the full moon, and a high number of fireballs, this shower is worth a look even for urban observers. The peak should occur at 2:00 UT on January 4, which is 10 PM on January 3 in the eastern standard time zone. The radiant doesn’t rise until 11 PM, but early observers might get the chance to see a few meteors shooting up from the northern horizon.

A full sky map showing comet Lovejoy and the location of the radiant of the Quadrantids meteor shower

The sky on January 3 at 11 PM. The meteor shower radiant is just rising in the NNE, and comet Lovejoy is in the south.

There are a large number of radiants located along the ecliptic from Cancer to Virgo. While none of these is sufficiently active to generate a shower, the overall meteor activity at this time of year is increased. If you have insomnia, or work third shift, this is a good time of year to go out on any clear night between midnight and dawn and look up. For details on a week by week basis, be sure to check out the American meteor Society website: http://www.amsmeteors.org/category/meteor-showers/

Moon

Full: Jan. 5
New: Jan 20

Planets

Mercury and Venus peek out of the sunset twilight together at the start of the month. Mercury reaches greatest eastern elongation on January 14. Being mid-month, you might think that means it’ll be visible in the evening all month, but as it heads back toward conjunction and away from Venus, its apparent motion speeds up, and it vanishes into the glare of the Sun around the 25th. The two planets are less than a degree apart on January 11. A day old young Moon joins the pair on January 21, but it will be difficult to spot even with a telescope. Venus meanwhile heads toward an early February conjunction with Neptune.

Venus and Mercury with the rays of the setting Sun

Venus and Mercury, less than half a degree apart, at 5:45 PM on January 11.

Mars continues its slow progress toward conjunction in late spring. It passes slowly through Capricorn and Aquarius this month. Look for it within 2 hours of sunset. It passes less than a degree from Neptune on the 19th, and there’s a good binocular conjunction of Mars, Neptune and a young Moon on the 22.

The starfield with Mars, Neptune, and Sigma Aquarii  marked.

Mars and Neptune, only 0.5º apart, at 8 PM on January 19. This image is about 1 1/2° across, so It shows what you might see through binoculars or a small telescope.

Mars, Neptune, and a young Moon above Venus on January 22nd at 7 PM.

Mars, Neptune, and a young Moon above Venus on January 22nd at 7 PM.

Jupiter is well up by 10 PM this month. It is in retrograde right now, so look for it between Leo and Cancer, headed slowly closer to Cancer. There is a nice conjunction with the gibbous moon on the 7th.

Jupiter and the Moon in the east at 10 PM on January 7.

Jupiter and the Moon in the east at 10 PM on January 7.

Saturn is the gem of the dawn skies this month. Between Libra and Scorpio, it is best viewed around 7 AM at the beginning of the month, and around 6 AM at the end. There should be a stunning grouping of Saturn, Scorpio’s claws, and a waning crescent moon on the morning of January 16.

Saturn , the lone planet of the eastern predawn skies. Shown here at 7 AM on January 16.

Saturn , the lone planet of the eastern predawn skies. Shown here at 7 AM on January 16.

Deep sky Objects

Early sunsets and clear, dry air make January one of the best months for deep sky observing with a small telescope. Of course, you should definitely bundle up!

The Orion nebula, or M42, is one of the nicest objects. Binoculars are enough to show a hint of fuzz and the cluster of the stars. A small telescope resolves the 4 young type O stars at the core even in very bad skies.

January is a good time to catch the Beehive cluster, or M44, in Cancer. A naked eye object in dark skies, it shows up nicely in binoculars or a small telescope even in badly light polluted skies. Find it by about half way between Castor and Regulus.

The early sunset also means you can still catch the Andromeda galaxy, M31 around 9 pm.

While you’re in that area,be sure to look for the Blue Snowball planetary nebula, NGC 7662. A nebula, sky, or O2 filter help a lot with this in light polluted skies.

Full sky map for 9 PM on January 15.

Full sky map for 9 PM on January 15.