Skywatch Line for Wednesday, February 10th and Thursday, February 11th, 2016

This is the Dudley Observatory Skywatch Line for Wednesday, February 10th and Thursday, February 11th written by Louis Suarato

The 8% illuminated, waxing crescent Moon sets around 8 p.m. Thursday night at the lower end of the constellation Pisces. The Moon reaches perigee, its closest distance to Earth during this lunar cycle, at 9:41 p.m. EST Wednesday. At that time, the Moon will be 226,403 miles from Earth. Since this perigee occurs only two days from the New Moon phase, expect higher, and lower, than normal tides. Jupiter, the first of the naked-eye visible planets to rise, appears over the eastern horizon thirteen minutes before the Moon sets. Thursday night, two of Jupiter’s Galilean moons and their shadows cross the planet. Europa’sshadow crosses the face of the gas giant from 9:02 to 11:51 p.m. EST, followed by Europa itself from 10:51 p.m. to 1:00 a.m. EST. Io’s shadow transit begins at 12:51 a.m. EST, Followed by Io at 1:26 a.m. EST. Io’s shadow transit ends at 3:06 a.m. and Io’s transit ends at 3:40 a.m., Friday. Io completes four orbits, and Europa completes two orbits in the same time that Ganymede completes one orbit around Jupiter. Callisto, the outermost of the Galilean moons, at about 1,168,000 miles, takes about seven Earth days to complete one orbit around the planet. 

The constellation above Jupiter is Leo, with its brightest star, Regulus. The two inner stars of the Big Dipper’s bowl,  Megrezand Phecda, point to Regulus. A precursor to Spring, the constellation Leo raises its head higher in the evening sky as the vernal equinox approaches. Mars, the next naked-eye visible planet to rise, appears about 45 minutes after midnight. Mars continues to grow in brightness and apparent diameter this month. By the end of the month, Mars will be 0.3 magnitude and increase to an apparent diameter of  8.6″. Saturn rises next at 2:49 a.m. in Scorpius. Saturn and Mars are moving toward each other, and the gap between them closes from 26 degrees to 18 degrees during the month. Next up is Venus at 5:30 a.m.,followed by Mercury 15 minutes later. Try to catch the two innermost planets before Mercury gets lost in the Sun’s glow toward month’s end. 

The 2016 Albany Area Amateur Astronomers Star Party Schedule has been posted! Mark your calendars and we look forward to seeing you there! The schedule can be found here:

Skywatch Line for Friday, February 5, through Sunday, February 7, 2016

This is Dudley Observatory’s Skywatch Line for Friday, February 5, through Sunday, February 7, 2016, written by Alan French.

Approaching new, a slender old Moon graces the morning sky early this weekend. On Saturday morning at 6:15 am the Moon, Venus, and Mercury will form a compact trio above the east southeastern horizon. The Moon will be highest and almost directly above Mercury, which will be just over four degrees above the horizon. Venus will be to their right and a height midway between the two.

This lovely grouping would make a good target for photographers.

By Sunday morning the Moon will be farther south and just above the horizon at 6:15 am. By 6:30 am it will be three degrees high. If the skies near the horizon are clear it should be a pretty sight. By Monday morning the Moon will be too close to the Sun to spot.

The weekend starts with a nice pass of the International Space Station (ISS) over our area early Friday evening. The ISS looks like a very bright star as it glides across the heavens, and is brighter than any true stars when it is high in the sky. Some times will be given in hours, minutes, and seconds. I often do not spot the ISS until a little after its “first appearance,” when it is higher above the horizon. To me, its highest point in the sky also seems higher than the numbers imply. If you miss it as it rises, it’s brighter and easies to spot at its highest point.

The ISS will first appear seconds before 6:14 pm coming up from the west southwestern horizon. It will be highest at 6:17 when 54 degrees above the north northwestern horizon. It will move into the Earth’s shadow and fade from view when 17 degrees above the northeastern horizon seconds after 6:19:18.

As the ISS glides across the sky it will move up along one side of the Great Square of Pegasus, below the “W” of Cassiopeia, and above Polaris, the North Star. As it moves down toward the northeastern horizon it will pass in front of the Big Dipper’s bowl.

Skywatch Line for Wednesday, February 3rd and Thursday, February 4th, 2016

The Dudley Observatory Skywatch Line for Wednesday, February 3rd and Thursday, February 4th written by Louis Suarato

Wednesday night, through overnight Thursday, the skies will remain moonless until the 20% illuminated, waning crescent Moon rises at 3:33 a.m. in the constellation Ophiuchus. Comet C/2013 US10 Catalina has passed Ursa Minor and Polaris, and is on its way to the constellation Camelopardalis. Camelopardalis is a faint constellation, and the 18th largest. Without any bright stars to use as a starting point to find Comet Catalina, I recommend using Polaris. The comet can be found about 10 degrees directly above Polaris at 9 p.m., and slowly moving to Polaris’ upper left throughout the night. Further to the left of the comet, is the Double Cluster. The Double Cluster, also known as Caldwell 14, is comprised of the naked-eye visible open clusters NGC 869 and NGC 884. These open clusters in the constellation Perseus, are about 7,500 light-years away and are estimated to be about 12.8 million years old. The Double Cluster is best viewed through binoculars or a small telescope. The two inside stars of the shallower “V” in the constellation Cassiopeia point to the Double Cluster.

The first of the five naked-eye visible planets to rise is Jupiter. Jupiter rises at 8:17 p.m. Wednesday. The Galilean moons Ganymede, Callisto, and Io will be to one side of Jupiter, and Europa will be alone on the other side, until 1:39 a.m., when Io is occulted by the solar system’s largest planet. Thursday night, beginning at 6:36 p.m., Callisto dims significantly, as it is eclipsed by Jupiter’s shadow. At about the same time, Europa’sshadow begins to transit the planet, followed by Europa an hour and a half later. Europa’s transit ends at 10:41 p.m. Thursday.

The second naked-eye visible planet to rise is Mars. Mars rises a few minutes before 1 a.m., Thursday. Mars’ brightness increases from +0.8 to +0.3 magnitude this month. Saturn rises next at 3:14 a.m., with its 26 degree angle of tilt providing a wonderful telescopic view of its rings. The crescent Moon rises at 3:38 a.m., and will be about 8 degrees to Saturn’s lower left. Venus is up next at 5:28 a.m., shining at a brilliant -3.9 magnitude. Last up is Mercury at 5:44 a.m., less than three degrees below Venus.

Skywatch Line for Monday and Tuesday, February 1st and 2nd, 2016

This is the Skywatch Line for Monday and Tuesday, February first and second.

The Sun sets at 5:08 PM; night falls at 6:45. Dawn breaks at 5:32 AM, and ends with the Sun rising at 7:09.

For those suffering from winter, there is hope. Last December 22, the Winter Solstice, there were only nine hours of daylight; Monday, the Sun sets ten hours after sunrise. Days lengthen until the Summer Solstice, June 20.

There are no bright planets during Twilight. Nightfall reveals three dim solar system members. Neptune, in Aquarius, lies five degrees above the southwestern horizon, making observation difficult. It sets at 7:19 PM. Uranus is higher in the southern sky, in Pisces. It shines at sixth magnitude. Difficult asteroid 4Vesta glows in Cetus at sixth magnitude; it is about five and-a-half degrees below Uranus. Uranus and Vesta set by 10:38 PM.

By 9 PM, Comet Catalina is well up in the North. The comet lies 9 degrees above Polaris, the North Star. The comet is flying away from earth and becomes dimmer, at 7th magnitude. Catalina is circumpolar and is best seen at 10:30 PM, when it is highest.

Jupiter is up by 9 PM. The giant planet is located between Leo’s hind legs and the head of Virgo. It blazes at minus 2.4 magnitude and is six degrees up in the East. While binoculars show the planet and four Galilean moons, telescopes expose The Great Red Spot, a giant storm at 5:15 AM on Tuesday, and at 1:06 AM Wednesday. Telescopic observers can witness the Jovian moon Io march its shadow across the planet at 4:29 AM Wednesday, and Io itself at 5:14 AM.

Mars follows Jupiter by rising after Midnight. Mars appears next to the star known as Zubenelgenubi, in Libra. This month Mars crosses Libra and becomes bigger and brighter in our telescopes and binoculars. The 23 day-old Moon rises before Dawn in Libra; it blazes at minus 9th magnitude Tuesday morning, and minus 8th magnitude on Wednesday. The Moon shrinks from one-third to about one-quarter lit. Saturn rises next at 3:19 AM in Ophiuchus; observers with telescopes can enjoy its ring system. Tuesday finds Saturn eight degrees above the bright red star Antares and five degrees from the Moon. Venus rises at 5:24 AM, appearing second to the Moon in brightness. At Dawn, it is only one degree above the horizon; but, by civil dawn, it is ten degrees higher and appears about 85 percent lit. It shrinks slightly, but becomes more illuminated. Mercury, bringing up the rear, rises about 5:43 AM, and by civil dawn, is eight degrees high in the southeast. Mercury shines at zero magnitude and a bit more than half illuminated through our telescopes.

Like Earth, the sky is divided into imaginary lines. Lines of Right Ascension run from Polaris to the horizon, while lines of Declination measure altitude from the celestial equator. A third line is the Ecliptic. It illustrates the path of the Sun, Moon and planets. It is usually difficult to picture this path when gazing at the night sky. Civil dawn makes it easy. Any time during dawn, start with Jupiter, then Mars, the Moon, Saturn, Venus and Mercury. All are exactly on, or very near the ecliptic. Once you connect these points, your understanding of planetary motions will be enhanced.

Skywatch Line for Friday, January 29, through Sunday, January 31, 2016

This is Dudley Observatory’s Skywatch Line for Friday, January 29, through Sunday, January 31, 2016, written by Alan French.

Reaching last quarter shortly before midnight Sunday, a waning gibbous Moon rises late in the evening over the weekend. Moonrise is at 10:49 pm Friday, 11:46 Saturday, and 12:43 am Monday morning. (In Monday morning’s sky, it will appear a bit less than half full – a waning crescent.)

The pre-dawn gathering of planets continues. This is the first time in more than a decade it is possible to see all the naked eye planets in the morning sky. (If you are where the skies are dark and free of light pollution, it is just possible to spot Uranus by eye, but it is not generally considered one of the “naked eye” planets and was not spotted before the invention of the telescope.)

During the past week Mercury has been moving higher, into darker sky, and brightening, so it should be easier to spot this weekend than last. The Moon has also joined the lineup.

To see the planets, you’ll want to look at 6:30 am. (Much earlier and Mercury will be too close to the horizon. Much later and the morning sky will be too bright.) At 6:30 am Mercury will be six degrees above the horizon toward the east southeast. You’ll need a good view in that direction and skies there free of haze and clouds.

Brilliant and eye catching Venus will be almost ten degrees above the southeastern horizon. If you couldn’t find Mercury, look for it to the left and slightly below Venus, at about the 8 o’clock position and 8 degrees away. (A fist held at arm’s length spans 10 degrees across the knuckles.)

If you did find Mercury, think of the former planet, now dwarf planet, Pluto, because it sits, invisibly, less than a degree to Mercury’s right.

Mercury is now 133.8 million kilometers away and Pluto lies at a distance of just over 5 billion kilometers. Light from Mercury takes just over 7 minutes to reach your eyes. If you could see Pluto its light would have been traveling for 4 hours and 42 minutes.

To the upper right of Venus, look for fainter, yellowish Saturn. If you’ve found Saturn you should see the reddish star Antares to its lower right. Well to the right of and higher than Saturn, almost due south, you’ll find reddish Mars. Completing our lineup of planets, Jupiter shines brightly in the west southwestern sky.

On Saturday morning the Moon will be between Mars and Saturn, lying closer to Mars. By Sunday the Moon will be closer to Mars, and Monday morning will find it very close to Mars, only 1.5 degrees away.

Skywatch Line for Wednesday, January 27th and Thursday, January 28th, 2016

This is the Dudley Observatory Skywatch Line for Wednesday, January 27th and Thursday, January 28th, written by Louis Suarato

The 85% illuminated, waning gibbous Moon rises at 8:55 p.m. providing about 4 hours for deep sky observing. The moonless sky may provide a great opportunity to view Comet C/2013 US10 Catalina. The comet is visible in the evening, and about 7 p.m., is located between the Big and Little Dippers. Wednesday night, use the same two outermost stars on the Big Dipper’s bowl, that you use to find Polaris, to find Comet Catalina. The comet will be about two-thirds of the way between the pointer stars of the Big Dipper and Polaris, the North Star. The comet is estimated to be near 6th magnitude brightness and has been seen by observers with binoculars. As always, the darker the skies, the better the seeing, so head out to your favorite dark sky site to see this comet.

When the Moon does rise, it will have company. Look a few degrees above the Moon for Jupiter. If you look at Jupiter using a telescope after 9 p.m. Wednesday, you’ll see Callisto ending its transit across the face of Jupiter. Callisto, which is about the size of Mercury, is the second largest Galilean moon after Ganymede, and the third largest moon in the solar system after Ganymede and Saturn’s moon, Titan. Callisto has been visited by NASA’s Voyager 2 spacecraft in 1979, and multiple times after the Galileo spacecraft reached Jupiter’s orbit in 1995. The spacecraft Juno, which was launched on August 5, 2011, is scheduled to arrive at Jupiter on July 4th of this year. Juno is expected to provide more information about Jupiter’s atmosphere, including composition, temperature, cloud motions and other properties.

The pre-dawn sky continues to offer the opportunity to view five naked-eye planets. At 6 a.m. Thursday, Saturn, Venus and Mercury can be seen low on the southeastern horizon. Saturn will be the highest at approximately 18 degrees. Venus and Mercury are much closer to the horizon. You may require binoculars to see Mercury. Mars will be 32 degrees over the southern horizon, and Jupiter can be found to the right of the Moon in the southwest.

Skywatch Line for Monday and Tuesday, January 25th and 26th 2016

This is the Skywatch Line for Monday and Tuesday, January 25th and 26th 2016, written by Joe Slomka.

The Sun sets at 4:48 PM; night falls at 6:37. Dawn breaks at 5:38 AM and ends with sunrise at 7:16.

The twilight sky contains no bright planets. Nightfall reveals Neptune in Aquarius; it looks like a blue-green eighth magnitude star about eleven degrees high. Similar looking Uranus lies in Pisces; it shines at magnitude 5.8. The asteroid 4Vesta is positioned in Cetus; it’s a tiny eighth magnitude speck about six arc-seconds below Uranus. All three set by 11 PM.

By 9 PM, the Moon blazes about three degrees from Leo’s bright star Regulus, the lion’s front paw. Tuesday evening finds a slimmer Moon close to his hind legs. The Moon sets during daytime.

At 9 PM, newly risen Jupiter hugs the eastern horizon and shines at magnitude minus 2.3. While binoculars show the planet with four Galilean moons, telescopes enable views of the Great Red Spot (a giant storm on Jupiter) at 4:30 AM, Tuesday and at 12:21 Wednesday morning.

Comet Catalina is about 38 degrees high at about 9 PM. It emerges as a sixth magnitude fuzzy object between the Little Dipper and the stars of Draco. Best observed at 3:46 AM on Tuesday, Catalina is so close to the North Pole that it does not rise or set, but circles the sky. – what astronomers call “circumpolar.”

By Midnight, the constellation Perseus dips into the western sky. Bright star Algol dims for two hours, centered about 12:11 AM. Algol is an eclipsing binary, which means that an orbiting body partially blocks the star’s light from view.

Dawn is where the action is. First, is the Moon residing in Leo’s legs. Next is Jupiter, midway between Virgo’s head and Leo’s tail. The Red Planet, Mars, rises at 1:06 AM and, by Dawn, is best observed to be only six degrees from Alpha Librae, the bright star Zubenelgenubi. Now shining at first magnitude, Mars gradually grows bigger and brighter in our eyepieces; under magnification, it appears about 90 percent illuminated.  Saturn is next, in Ophiuchus. Saturn glows at 0.5 magnitude; its off-white appearance readily identifies it. Venus blazes in Sagittarius at magnitude minus 4.0; under moderate powers, it appears about 83 percent illuminated. Mercury brings up the rear, thirteen degrees below Venus; it rises at about 5:53 AM and displays at zero magnitude and a third illuminated. This planetary lineup makes spotting Mercury difficult; it becomes easier in coming days.

High in the South about 9:00 PM is the object astronomers call M45, but commonly named the Pleiades.  The Pleiades form a mini dipper that is so distinctive that virtually all cultures have named and worshiped it.  Many peoples used it as a farming calendar.  When the Pleiades rise in the Autumn, it is time to harvest.  When it sets in the spring, it is planting time.  Ancient Greeks called it the “Seven Sisters”, and other societies had similar names, giving rise to the legend of the “Lost Pleiad”.  One of the stars apparently dimmed in the past, because most people can see only six stars without optical aid.  Most likely, the star Pleione was brighter in ancient times and had recently dimmed.

Skywatch Line for Friday, January 22, through Sunday, January 24, 2016

This is Dudley Observatory’s Skywatch Line for Friday, January 22, through Sunday, January 24, 2016, written by Alan French.

The Moon is full on Saturday night and will be a lovely sight rising in the east northeast at 4:54 pm. With a nice foreground, the rising full Moon can make a lovely photograph.

Some photographers carefully plan shots of the rising Moon, positioning their camera so they can photograph it rising near a prominent landmark. To do this you need to know just where the Moon will rise. One way to research this is to observe it rising a day earlier, noting the difference it its position then and on the following night. The Moon will rise at 3:54 pm on Friday afternoon, and its rise will be four degrees farther north than it will be on Saturday. If you hold your hand, fingers close together, at arm’s length, it spans five degrees across the first three fingers.

Planning a photo of the setting full Moon is simpler since you can see it as it moves down toward the horizon. The Moon will set at 7:20 am Sunday.

Often its shape will appear distorted when it is low in sky and it may also be a lovely orange color.

Although the full Moon’s brightness washes out the fainter stars and many deep sky objects, some take advantage of the moonlit landscape to hike, snowshoe, or cross country ski.

Five planets now grace the morning skies, although Mercury is close to the horizon and may be difficult to spot. You’ll need a good view and clear skies low to the east southeast and good timing to catch it. Look for it around 6:30 am when it will be three degrees above the horizon. It will be moving higher, but the skies will also be increasingly brightened by morning twilight. If it eludes you, use Venus as a landmark. (Mercury will be slightly higher and easier on Sunday and Monday.)

Brilliant Venus is a bit higher and more to the south. Its brightness makes it impossible to miss. Mercury will be to its lower left, at about the 8 o’clock position, and 14 degrees away. (If you hold your hand at arm’s length, with the outer fingers extended, they span 15 degrees at their tips.)

To the upper right of Venus, look for fainter, yellowish Saturn. If you’ve found Saturn you should see the reddish star Antares to its lower right. Well to the right of and higher than Saturn, almost due south, you’ll find reddish Mars, Completely our lineup of planets, bright Jupiter shines high in the west southwestern sky. This lineup will be closest together on Monday morning.

Skywatch Line for Wednesday, January 20th and Thursday, January 21st, 2016

This is the Dudley Observatory Skywatch Line for Wednesday, January 20th and Thursday, January 21st written by Louis Suarato

Celebrate Buzz Aldrin’s birthday by viewing the 88% illuminated, waxing gibbous Moon which rises at 2:04 Wednesday afternoon. After sunset, the Moon will be high over the eastern horizon between the constellations Taurus and Orion. The bright star to the upper right of the Moon is Aldebaran, and the bright star below the Moon is Betelgeuse. Shining at magnitude 0.45, Betelgeuse is the ninth brightest star in the night sky and the second brightest in the constellation Orion. This red supergiant is estimated to be about 640 light-years from Earth, and its diameter is 700 times that of our Sun, or 600 million miles. Betelgeuse is at the center of the winter hexagon asterism, and along with Sirius, in Canis Major, and Procyon, in Canis Minor, form the Winter Triangle.

Comet C/2013 US10 Catalina reached its closest approach to Earth last weekend and is estimated to be as bright as 6th magnitude. Wednesday night, look for the comet by using the innermost stars making up the Big Dipper’s bowl. At around 9 p.m., Comet Catalina will be about 20 degrees above the north-northeastern horizon. The two stars of the Big Dipper’s bowl closest to the handle point northward towards the comet. Look about 15 degrees from the northern most star, Megrez, to find Comet Catalina.

The Albany Area Amateur Astronomers hold their January meeting this Thursday night beginning at 7:30 p.m. at miSci in Schenectady. The topics for this month’s meeting include a discussion by Alan French for making a light shield for a laser pointer. Chunyu Wang will give a presentation on observing and photographing Comet C/2013 US10 Catalina. Alissa and Scott Johnson will share their experience refurbishing an 8-inch Meade Starfinder Dobsonian telescope and Dr. Willie Lee of the Mid-Hudson Astronomical Association, will lead a discussion on “Why Does Anything Exist?”, about the first milliseconds of the Universe. Members and non-members are welcome. Directions to miSci can be found at

Skywatch Line for Monday and Tuesday, January 18th and 19th, 2016

This is the Skywatch Line for Monday and Tuesday, January 18th and 19th.

The Sun sets at 4:50 PM; night falls at 6:40. Dawn breaks at 5:42 AM and ends with the Sun rising at 7:21.

The nine-day-old Moon rose this afternoon and, by twilight, is halfway up in Taurus. It blazes at magnitude minus ll on both nights.  The Moon is Tuesday night’s central feature. During its travels, the Moon occults, or eclipses, many relatively dim stars and occasionally blocks our view of a bright star. Tuesday night is one of those nights. At about 9:30 PM, the Moon begins to eclipse the bright red star Aldebaran in Taurus. Aldebaran reappears from behind the Moon at approximately 10:44 PM. This event can be seen with the naked eye, but is best observed through stabilized binoculars or telescope. The Moon sets during pre-dawn hours.

The darkening sky reveals planets Neptune and Uranus as well as asteroid 4Vesta. Eighth magnitude Neptune still resides in Aquarius, while sixth magnitude Uranus shines in Pisces. Vesta is about 34 arc minutes from the star 20 Ceti and eight degrees below Uranus. Finder charts for all three can be found in astronomy media.

By 9 PM the Big Dipper asterism rises in the North, and appears to stand upright on its handle. Comet Catalina is visible at sixth magnitude. Monday night, it appears about five degrees above double stars Alcor and Mizar, and also about four degrees below the bright star Thuban in the constellation Draco. Tuesday night finds Catalina about seven degrees above Alcor and Mizar. Catalina is now circumpolar, which means that it does not rise or set.

Neptune, Uranus and 4Vesta all set before Midnight, when the night shift takes over. Jupiter rose at 9:18 PM, and by Midnight stands about 26 degrees above the horizon between Leo’s hind legs and Virgo’s head. While Jupiter is visible to the naked eye and its four Galilean moons through binoculars, telescopes display more detailed events. The Great Red Spot (a giant storm) is visible Tuesday morning at 3:44 AM and at 11:36 PM on Wednesday. On Wednesday, the moon Io casts its shadow on Jupiter at 12:43 AM, followed by the moon itself at 1:42 AM; Io’s shadow leaves Jupiter’s face at 2:58 AM, followed by the moon itself at 3:56 AM.

Jupiter begins a morning planetary parade, first magnitude Mars emerges about 1:15 AM between Virgo and Libra. Saturn appears next at 4:08 AM in the dim constellation Ophiuchus. Its creamy color makes its presence obvious; telescopic views of its rings are not to be missed. Venus rises at 5:03 AM, blazing at minus fourth magnitude. At Dawn, it is about five degrees above the eastern horizon and appears about 82 percent illuminated in our telescopes.

The Albany Area Amateur Astronomers hold their monthly meeting at miSci on Thursday, January 21st, at 7:30 PM. This month’s theme is a potpourri of short talks given by several club members. As usual, all club events are free and open to the public. The meeting is cancelled if weather forces miSci to close.