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Dudley Observatory
Supporting research and education in astronomy, astrophysics, and the history of astronomy |
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Skywatch August 2005 Skywatch line for
August 3rd, 2005 The Sun sets tonight at 8:12
PM preceded by the waning crescent Moon, setting at 7:56 PM. New Moon occurs
Friday. Generally, though not exclusively, amateur astronomers think of Spring as “galaxy season.” However, several of the most prominent galaxies are visible, even in binoculars, during Summer nights. In order to locate them, we will use as our frame of reference the Big Dipper, the well known asterism which forms part of the constellation Ursa Major. Starting with the end of the bowl, and working our way round to the end of the handle of the Big Dipper, the stars are named Dubhe, Merak, Phad, also called Phecda, Megrez, Alioth, Mizar and Alkaid, which is also called Benetnasch. Drawing a line from Phad
through Dubhe and going about an equal distance beyond Dubhe, brings us close to
M 81, a spiral galaxy that is the third brightest galaxy in northern skies.
Less than a degree away, so that they are both visible in the same field in
binoculars and many telescopes, is M 82, a cigar shaped irregular galaxy.
Binoculars will reveal the shape of both galaxies and the sight is stunning in a
low power telescopic field. Appearing larger, though
dimmer, than M 81 is M 101. Whereas M 81 and M 82 are approximately eleven
million light years away, M 101 is 20 million light years distant. M 101 can be
found at the apex of a triangle whose base is the line from Mizar to Alkaid. Finally, in the constellation Canes Venatici, a little over three and a half degrees from Alkaid, “under” the handle of the dipper at 11:00 PM tonight, can be found M 51, popularly known as the Whirlpool Galaxy. Probably the first galaxy to be seen as having a spiral structure, M 51 has a satellite galaxy at the end of one of its spiral arms which, like the Whirlpool’s spiral arms, is readily visible in a moderate size telescope. M 51, at twenty-five million light years away, appears as a small, hazy patch in binoculars. Of course, the most easily viewed galaxy is our own Milky Way, which includes almost everything visible to the naked eye at night. From our vantage point in the northern hemisphere, only M 31 in Andromeda and, perhaps, M 33 in Triangulum, are objects beyond our home galaxy, visible without optical aid.
Skywatch Line for Monday, August 8 by Joe Slomka
The Sun sets at 8:07, with night falling at 10 PM. Dawn breaks at 4:03 AM, with sunrise taking place at 5:55. As the Sun sets three objects become visible. However, Venus is now so low, that trees or buildings may hide it. The three-day-old Moon lies roughly between Venus and Jupiter, and helps locating these setting planets. The Moon and Venus display phases, due to their positions relative to the Sun. So, in a telescope, Venus looks about eighty percent illuminated, while the Moon is only thirteen percent illuminated. Jupiter, because it is so far, does not display phases, but has a very extensive moon system. Anyone with ordinary binoculars can see the four moons that Galileo discovered.
Tonight the distant planet Neptune reaches opposition, which means that the Sun, Earth, and Neptune form a straight line. Neptune rises when the Sun sets, and sets at sunrise. Opposition also means that the planet is usually at its best to be observed. While Neptune is a gas giant, it is so far that it is easily mistaken for a star. In fact, Neptune can be seen with ordinary binoculars, but you must have a detailed chart, which helps identify it from similar looking stars.
Neptune was the last planet in the solar system for many years until Clyde Tombaugh discovered Pluto in the 1930s. Recently, observers have discovered other larger bodies beyond Pluto. The largest was just announced a week ago. Astronomers now realize that there is a “cloud” of asteroids and mini-planets that surround the Solar System. It is called the Kuiper Belt, after the Belgian astronomer who theorized its existence. Pluto and its companions are only larger members of this “belt.”
Mars rises shortly before Midnight and is best seen during the hours before dawn. Mars is the brightest object in that part of the sky. The southern pole now faces us. In a week, the Martian southern hemisphere will have its summer solstice. Since Mars takes about two years to orbit the Sun, each season lasts about six earth months.
Skywatch Line for
Tuesday, August 9th, 2005 Sunrise today was at 5:57
AM, and it will set tonight at 8:10 PM. It will rise tomorrow at 5:58 AM, and
will set tomorrow at 8:09 PM. The Moon is currently in a waxing crescent phase, with the First Quarter on the 12th. It rose at 10:26 this morning, and will set at 10:09 tonight. It will rise at 11:28 tomorrow morning and will set at 10:30 tomorrow night. Venus is very low in the
west after Sunset, and the Planet Jupiter is low in the west after Sunset.
Venus is the brighter of the two, and tonight, the Moon will be near Jupiter. The Summer Triangle of Vega, Deneb, and Altair is getting higher up in the sky each night in the north east. Running through the center of the triangle, is the Summer portion of our Milky Way Galaxy. Appearing as a dim smudgy band of light under dark skies, a pair of binoculars will reveal countless numbers of stars. And don’t forget about
the planet Mars, looking like an orange-reddish star rising about an hour or so
after midnight in the east. And beware of stories on the internet about Mars
making it’s closest approach to Earth in our lifetime. This information is
actually from the close approach in 2003. And don’t forget about
the Perseid Meteor Shower, which peaks on the morning of the 12th. Public Programs at the Suits-Bueche Planetarium at the Schenectady Museum, are on Saturdays and Sundays at 1, 2, and 3 P. M. The 1:00 program is “The Sky Above Mister Rogers’ Neighborhood”, a program for young people. At 2 P. M. is “Light Years from Andromeda”, and at 3 P. M. is a live narration of the Summer Sky. “Light Years From Andromeda” also plays Tuesday through Fridays at 2 PM. The two largest photos ever taken by the Hubble Space Telescope, will be on display in the planetarium lobby for the next several months.
Skywatch line for
August 10th Tonight the Sun sets at
8:03 PM followed by the waxing crescent moon, in the constellation Virgo at
10:27 PM. First quarter moon occurs Saturday. Around sunset, Venus is
readily visible at almost minus four magnitude, before it too sets at 9:28 PM.
Jupiter follows Venus, setting at 10:18 PM. By now, Jupiter is too low in the
sky to show much detail on the planet. However, the ever changing positions of
the Galilean moons can still be followed. Mars, which reaches
opposition this Fall, rises at 11:15 PM. At brighter than zero magnitude and
more than twelve arc minutes in diameter, Mars is starting to become an
interesting object in amateur telescopes. Easily visible is the south polar
cap. Moderate to large instruments will show some detail on the ball of the
planet. Once the sky darkens
sufficiently after sunset, many amateur astronomers are first attracted to the
southern horizon and the constellations of Scorpius and Sagittarius. Being well
below the celestial equator, the time to view the deep sky objects in this part
of the sky is fleeting. The area is full of such objects, including the
brightest globular cluster visible to northern observers, M 22 in Sagittarius,
and one of the most magnificent nebulae, the Lagoon Nebula. M22 can readily be
found with binoculars to the upper left of the top star in the teapot asterism,
Lambda Sagittarii. The Lagoon Nebula, also known as M 8, can be found by
scanning the sky north of the teapot’s spout. Once found, place M 8 toward the
bottom of the field. Less than one and one half degrees above M 8 can be found
M 20, the Trifid Nebula. Smaller and half a magnitude dimmer than the Lagoon,
typical binoculars will not show the gas and dust lanes which divide the nebula
into three parts, giving it its name. Additional globular clusters
abound in this part of the sky. Perhaps one of the easiest to locate is M 4 in
Scorpius. The brightest star in Scorpius is Antares, an unmistakable star of
the first magnitude whose name means “rival of Mars”. The name obviously
derives from its color, which is quite similar to the color of the planet. M 4
is visible in binoculars as a small, hazy patch to the right of Antares, below
the line formed by connecting Antares and the third magnitude star to its west. The center of our galaxy is located in the area where the constellations Scorpius and Sagittarius meet. It seems fitting, then, that the Milky Way appears to rise like steam from the teapot’s spout in Sagittarius.
Skywatch Line for Friday, August 12, through Sunday, August 14, 2005 by Alan French
This weekend is the peak of the annual Perseid meteor shower, one of the best-known and most reliable meteor showers. The Perseid meteor shower has been underway for a while, and local amateur astronomers saw a few last weekend. The shower's peak, however, extends from Friday, August 11, through Sunday, August 13. The best show was likely during the pre-dawn hours on Friday, but late Friday night and the hours before dawn on Saturday morning should provide a good show too.
For your best view of the Perseids, find a location away from city lights with a good view of the sky. A reclining lawn chair or sleeping bag provides a comfortable view. More meteors are seen after 1 AM, but a patient viewer during the earlier hours is sure to see some. The meteors can appear anywhere in the sky, so just be sure to look fairly high in the sky and pick a location where most of the sky can be seen.
Weather permitting, the Albany Area Amateur Astronomers will host a Perseid Meteor Watch beginning at 9:30 PM on Friday night, August 12, at the George Landis Arboretum in Esperance. If you enter Esperance traveling west on Route 20, watch for the arboretum sign on your right, immediately after crossing the bridge over the Schoharie River. After taking the right, follow the signs to the arboretum. Continue up the hill past the main parking area and farmhouse, and turn right into the Meeting House drive as you reach the top of the hill.
Beginning at 4:00 PM on Saturday afternoon, August 13, the Albany Area Amateur Astronomers will host a Sun/Moon party at George Landis Arboretum. Special telescopes will provide safe views of sunspots and prominences. Guests are invited to bring a picnic dinner to enjoy at sunset, and after dark, the program will continue with lunar observing.
Both the Perseid Watch and the Sun/Moon party are open to all, and there is no charge. They are canceled if the skies are mostly cloudy. Please call 374-8460 if the weather is questionable.
We continue to get questions about the upcoming historic close approach of Mars on August 27. Unfortunately, the e-mail promoting this is two years out of date, and this event happened back in 2003. Although the red planet will not be as close this year, Mars will be a fine sight at the end of October. For those of us in the northern United States, telescopic views should be better than they were in 2003 since the planet will be considerably higher in the sky and we will be looking through less of our turbulent atmosphere.
Skywatch Line for Tuesday, August 23rd, 2005 by Steven Russo, Planetarium Manager of the Suits-Bueche Planetarium at the Schenectady Museum.
Sunrise today was at 6:13 AM, and it will set tonight at 7:49 PM. It will rise tomorrow at 6:14 AM, and will set tomorrow at 7:47 PM.
The Moon is currently in a waning gibbous phase, with the Last Quarter on Friday. It rises at 9:47 PM, and will set a little after noon tomorrow.
Venus is very low in the west after Sunset, and the Planet Jupiter is low in the west after Sunset. Venus is the brighter of the two. During the next few nights, the two planets will move closer together, from our view on Earth.
The Summer Triangle of Vega, Deneb, and Altair is getting higher up in the sky each night in the north east. Running through the center of the triangle, is the Summer portion of our Milky Way Galaxy. Appearing as a dim smudgy band of light under dark skies, a pair of binoculars will reveal countless numbers of stars.
And don’t forget about the planet Mars, looking like an orange-reddish star rising about an hour or so after midnight in the east. And beware of stories on the internet about Mars making it’s closest approach to Earth in our lifetime. This information is actually from the close approach in 2003. And Mars will NEVER look as large as the Full Moon in the sky.
Public Programs at the Suits-Bueche Planetarium at the Schenectady Museum, are on Saturdays and Sundays at 1, 2, and 3 P. M. The 1:00 program is “The Sky Above Mister Rogers’ Neighborhood”, a program for young people. At 2 P. M. is “Light Years from Andromeda”, and at 3 P. M. is a live narration of the Summer Sky. “Light Years From Andromeda” also plays Tuesday through Fridays at 2 PM. The two largest photos ever taken by the Hubble Space Telescope, will be on display in the planetarium lobby for the next several months.
Skywatch Line for Wednesday, August 24th by Bernard Forman Tonight, the Sun sets at
7:42 PM. The waning gibbous Moon rises at 10:12 PM in the constellation Aries,
a little more than four and a half degrees to the upper left of Mars. Last
quarter occurs on Saturday. For different people,
Astronomy can be appreciated in many different ways. For many amateur
astronomers, there is great fun in hunting for dim, obscure objects millions
upon millions of light years away, which appear as nothing more than faint fuzzy
objects in the eyepiece. Once found, it is enough to contemplate that the light
of a distant galaxy started on its journey millions of years ago and that the
object is viewed, such as it can be, as it existed before mankind existed.
Others view the universe strictly as scientists, assured that everything is
subject to the laws of physics and the processes of chemistry, some of which
mankind still does not understand. And some find the
handiwork of God. The universe, scientists
tell us, started out around fifteen billion years ago, give or take a few
billion years. Scientists still struggle to describe the universe at its
inception, the so called Big Bang, but soon thereafter, at least on a cosmic
scale, the universe was made up primarily of hydrogen and some helium. Atoms
thereafter condensed from clouds of gas to form stars, the untold number of such
nuclear furnaces creating heavier elements later dispersed throughout the
universe by cataclysmic explosions. That process goes on still. On a dark
summer night, many an amateur, when viewing the Lagoon Nebula, sees new stars
recently formed from the gas and dust. Turning northward, in the constellation
Cygnus, we view the Veil Nebula, the remnant of an exploding star of long ago.
Hydrogen, helium and
heavier elements created inside stars long ago also condensed to form our solar
system, including Earth. And us. As the late astronomer Carl Sagan used to
say, we are made of star stuff. And billions of years from now, our atoms will
again be dispersed through the universe. There is a story about an
amateur astronomer who sets up his telescope in a national park. A ranger
objects, stating that the sky is not part of the park. But the amateur wins the
argument by pointing out that the park is part of the universe. So are we. And
we always will be. This skywatch is dedicated to the memory of my friend and colleague Gina.
THURSDAY AUGUST 25, 2005 by Barlow Bob Observe the Last Quarter
Moon on August 26th. Mars is getting very bright as it draws nearer Earth. It is rising earlier each night, around 10:30 p.m. at the beginning September. Late in the month it’s brighter than even the star Sirius. Stay up late enough for Mars to rise high in the sky, and you will find that it’s displaying a globe large enough to offer a chance for very fine telescopic views. Saturn emerges from morning
twilight low in the east-northeast during August. Mercury reached greatest
maximum separation from the Sun on August 23rd, when it glowed below
or lower left of Saturn at dawn. In the last week of August use binoculars to
look for M44, the Beehive Cluster of stars to the lower left of Saturn. Observe the star at the
foot of the Northern Cross, or nose of Cygnus the Swan. This is the beautiful
blue and gold colored double star Albireo. Notice the difference in colors in
binoculars and a telescope. You will also notice a field of view filled with a
large number of stars. You are observing our Milky Way Galaxy that runs right
through Cygnus. Sweep across the night sky, using binoculars or a telescope at
low power. Start at the teapot-shaped constellation Sagittarius. Then move north
through Aquila the Eagle, past Altair the bright Summer Triangle star. Continue
into Cygnus and follow it all the way to the northern horizon in Cassiopeia. Notice the variety of the colors of stars and clumps of star clusters, sprinkled along the path of the Milky Way. You will notice that stars look like diamonds, sapphires and rubies on black velvet.
Skywatch Line for Monday, August 29 by Joe Slomka This is the Skywatch Line for Monday, August 29. The Sun sets at 7:43, ending with nightfall at 9:16. Dawn breaks at 4:37 and ends with sunrise at 6:18. As the sky darkens, two bright objects hover close to the southwestern horizon. Venus is brighter and lower. Jupiter is dimmer and above. For the past week, the two have been closing. Tonight, they are only three degrees apart; by September 1 they are closest. After that, Venus climbs higher while Jupiter sinks into the twilight. If the skies are clear, try to track this cosmic switch. These planets are so low that trees or hills may hide them. By midnight, Mars is well up. It is easily identified by its bright red color. Mars continues to grow brighter and larger, in preparation for this Fall's close approach. The beautiful Pleiades star cluster lie to Mars' left. This group is marvelous in binoculars. Mars is best observed in pre-dawn skies in a moderately sized telescope. Also at midnight, the variable star Algol dims. Algol varies because a darker body orbits Algol and blocks some of its light. This event happens on a regular basis. It takes about two hours for Algol to dim and then another two to recover. Since the stars were thought to be pure and unchanging, a star that varied must be called a "Demon Star." Predawn skies offer not only Mars, but also a very thin crescent Moon, between the twins of Gemini. Saturn also is worth observing. The Cassini-Huygens space probe continues to send back intriguing photos and data of the Ringed Planet. Saturn appears as a bright cream-colored object next to the dim constellation Cancer, the Crab. If you have binoculars, move them two degrees to the left. There is the beautiful star cluster named the "Beehive." It truly looks like a swarm of bees. The pairing presents a truly magnificent view. Finally, Mercury struggles to be seen in the sunrise. It is brighter than Saturn, but significantly to Saturn's lower left. Again, trees and hills may hide this elusive planet. Clear Skies Joe Slomka Skywatch Line for Tuesday, August 30th, 2005 by Steven Russo This is the Dudley Observatory Skywatch Line for Tuesday, August 30th,
2005, written by Steven Russo, Planetarium Manager of the Suits-Bueche
Planetarium at the Schenectady Museum.
Sunrise today was at 6:21 AM, and it will set tonight at 7:37 PM. It will
rise tomorrow at 6:22 AM, and will set tomorrow at 7:35 PM.
The Moon is currently in a waning crescent phase. It rises at 1:46 AM,
and setting this evening at 6:07.
Venus is very low in the west after Sunset, and the Planet Jupiter is
low in the west after Sunset. Venus is the brighter of the two. Tonight,
these two planets are less than 3 degrees apart..
The Summer Triangle of Vega, Deneb, and Altair is getting higher up in
the sky each night in the north east. Running through the center of the
triangle, is the Summer portion of our Milky Way Galaxy. Appearing as a dim
smudgy band of light under dark skies, a pair of binoculars will reveal
countless numbers of stars.
And don’t forget about the planet Mars, looking like an orange-reddish
star rising at around 11:00 PM in the east. And beware of stories on the
internet about Mars making it’s closest approach to Earth in our lifetime.
This information is actually from the close approach in 2003. And Mars will
NEVER look as large as the Full Moon in the sky.
Public Programs at the Suits-Bueche Planetarium at the Schenectady
Museum, are on Saturdays and Sundays at 1, 2, and 3 P. M. The 1:00 program
is “The Sky Above Mister Rogers’ Neighborhood”, a program for young people.
At 2 P. M. is “Light Years from Andromeda”, and at 3 P. M. is a live
narration of the Summer Sky. “Light Years From Andromeda” also plays
Tuesday through Fridays at 2 PM.
The two largest photos ever taken by the Hubble Space Telescope, will be
on display in the planetarium lobby for the next several months.
Skywatch Line August 31, 2005 By Bernard Forman
The Sun sets tonight at 7:31 PM preceded by the waning crescent Moon at 6:30 PM. New Moon occurs on Saturday, September 3rd.
At sunset, low in the west southwest in the constellation Virgo, Venus shines at minus four magnitude with Jupiter, not quite minus two magnitude, one and a half degrees to its upper left. Venus sets at 8:55 PM followed by Jupiter at 9:03 PM. It you can’t readily find them, try scanning the horizon after sunset with binoculars.
Working from west to east, Neptune, at eighth magnitude, is in the constellation Capricornus, followed by Uranus, in the constellation Aquarius, slightly brighter than sixth magnitude. While both may be glimpsed with binoculars, a telescope will be necessary to discern their true nature, although both are small and neither will show any detail.
Clearly, the most interesting planet, now and for the next several months, is Mars, which rises at 10:17 PM in the constellation Aries. At minus one magnitude and with an apparent angular diameter of just over fourteen arc seconds, Mars will continue to brighten and grow in apparent size until it reaches opposition in early November. Even now, moderate size telescopes will reveal markings on the ball of the planet, as well as the south polar cap. While Mars will not be as close as it was for the 2003 opposition, it will be considerably higher in the sky, thus affording observers much improved conditions for observing the red planet.
By 11:00 PM Scorpius has already set and Sagittarius is near the horizon in the southwest. Still prominent west of the meridian are the summer constellations of Cygnus and Lyra, with Hercules heading for the horizon in the west. Meanwhile, the Fall constellations of Pegasus and Andromeda are becoming prominent.
Looking slightly east of the meridian and high up, the Great Square of Pegasus is unmistakable. All four star of the square are between second and third magnitude. Few if any stars are visible within the square, except under optimum conditions, namely a dark, transparent sky. The second magnitude star in the northeast corner, the brightest of the four, is Alpheratz, and is actually in the constellation Andromeda. The two lines of stars trailing Alpheratz to the east are part of Andromeda. With these Fall constellation already prominent, cool Autumn weather can’t be far behind. And rising in the east, you may be able to glimpse the Pleiades, a large open cluster also known as the Seven Sisters, which always reminds us of the winter to follow. |
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