September Skylights
Jupiter and Saturn continue to be the dominant evening planets until later in the month when Mars steals their crown. Venus reigns in the dawn sky.
As twilight falls you will locate conspicuous Jupiter to the south, with Saturn following a little distance in its wake. Although they both came to opposition a few months ago, they will be more favourably placed now for observation at a convenient hour. Both are very rewarding to view with smaller instruments, even binoculars are sufficient to reveal the Galilean moons of Jupiter, but not quite the rings of Saturn, for which you will require a small telescope at least to view them. You should note the banding on Jupiter’s disk, perhaps even the great red spot when orientated towards us. At Saturn (apart from the rings) you may also note Titan, Saturn’s largest moon, which resembles a bright, but obvious speck near to Saturn.
Have a little patience at the eyepiece when viewing Jupiter and Saturn as neither are particularly high above the horizon. The Moon passes below Jupiter and Saturn on the 24th and 25th respectively.
Already conspicuous to the eye in the early morning sky, Mars is now rapidly gaining in brightness, as it heads towards opposition in October and by the end of September will become the dominant presence in the late evening sky with its distinct orange hue. Look for Mars rising in the east when Jupiter and Saturn lie to the south. Telescopically Mars is improving through the eyepiece; just don’t expect it to be the size of Jupiter’s disk. Even when Mars reaches opposition, it will only appear half the size of Jupiter’s disk. If there are no obscuring Martian dust storms, you will be gazing at the surface itself. Apart from our moon, Mars is the only other body in the solar system where the surface is visible to typical amateur instruments. The waning moon passes below Mars on the 5th.
If you are an early riser look for brilliant Venus quite high in the eastern dawn sky, it can hardly be missed! On the morning of the 14th Venus resides below the open star cluster known as the ‘Beehive’ or M44, in Cancer, with a very slim moon visible above the cluster. The vista should make for a fine sight in binoculars.
The Autumnal Equinox
By astronomical convention autumn officially commences in the northern hemisphere on the date of the Autumnal Equinox, when from our perspective the Sun re-crosses the celestial equator and tracks southwards again, arcing ever lower in the sky. The date of the equinox this year falls on September 22nd and, like the spring equinox, this is when neither of Earth’s poles are inclined towards our nearest star so that all locations experience roughly equal hours of daylight and darkness. The northern hemisphere will then continue to tilt away from the Sun with evenings drawing in once again as we head through autumn and into winter.
The September Night Sky
With the resumption of astronomical twilight (true darkness) last month, the vast majority of stars are now visible before 10pm, making it somewhat easier for a casual observer to identify constellations in the night sky.
As twilight falls look for Arcturus, the brightest star in the summer sky over in the west. Overhead, lovely Vega in Lyra catches the eye, whilst low to the north, Capella in Auriga scintillates above the horizon. These are the three brightest stars north of the celestial equator visible from Britain. Each has a distinct hue: Arcturus appears orange, Capella, white, and Vega a lovely steely blue colour. High in the NW, look for the familiar saucepan outline of the ‘Plough’ – part of Ursa Major the Great Bear. The three stars marking the curved handle point down in the direction of Arcturus, located at the foot of Bootes, the herdsman. Note the delicate starry circlet of Corona Borealis, the Northern Crown situated to the upper left of Arcturus. Returning to the Plough, use the ‘pointer’ stars in the ‘bowl’ to locate the pole star, Polaris, in Ursa Minor by extending an imaginary line through them and continuing on a couple of hand spans to a relatively conspicuous, but solitary star.
Two large and sprawling groups occupy much of the SW aspect of the sky. The figure of Hercules, best identified by the ‘keystone’ asterism, stands upper left of Corona, whilst the vast and rather faint outline of Ophuichus, the Serpent Bearer, extends down from Hercules towards the SW horizon. As soon as twilight deepens in this direction look for the bright orange hue of Antares in Scorpius just above the horizon.
Should sky conditions be transparent, the asterism known as the ‘Teapot’, the most distinctive part of Sagittarius the Archer, may be traced above the S horizon. There are rich pickings in this part of the sky including numerous star fields, deep sky objects and the galactic centre. Jupiter and Saturn reside left of the ‘teapot’ asterism.
Following Sagittarius above the S horizon, Capricornus, the Sea Goat, heads an aquatically themed constellation parade which continues with Aquarius, the Water Bearer, low in the ESE and Pisces, the Fish, extending up from the east. If sky conditions are not ideal these groups can be hard to trace, in particular Pisces. However, for the time being, Mars glows fiercely at the foot of Pisces.
High overhead to the south and east, reside three bright stars. Vega, in the small geometric pattern of Lyra, is the most conspicuous, whilst to the east, Deneb sits at the tail end of Cygnus, the swan. Pearly white Altair resides midway up in the south in Aquila, the Eagle. These three stars form the asterism referred to as the ‘summer triangle’. Within the confines of the ‘summer triangle’ note the small stellar arrow shape of Sagitta, together with the close-knit group of Delphinus situated to its left. Both these small constellations do, with a little imagination, resemble the things they represent. Bizarrely Delphinus is sometimes known as ‘Job’s coffin’.
Over in the NE the great hero Perseus begins to climb away from the horizon, whilst above, the familiar ‘W’ pattern of Queen Cassiopeia holds court. Her daughter, Princess Andromeda, located to the lower right, is marked by a chain of stars extending towards the winged horse Pegasus, which occupies the mid regions of the E sky. Pegasus is best identified by ‘the great square’ an asterism comprising four stars that enclose a seemingly barren area of sky. The asterism serves as a useful signpost in locating numerous other stars, deep sky objects and constellations in the autumn sky, including the Andromeda galaxy, which is visible as a misty patch to the naked eye on dark moonless nights, upper left of the square. This is for next month however. Clear skies!
Mark Dawson,
Whitby and District Astronomical Society
WDAS usually meets in room H1, Caedmon College, Normanby campus (Whitby College). New members most welcome.
www.whitby-astronomers.com
email: spanton33@talktalk.net
.
As twilight falls you will locate conspicuous Jupiter to the south, with Saturn following a little distance in its wake. Although they both came to opposition a few months ago, they will be more favourably placed now for observation at a convenient hour. Both are very rewarding to view with smaller instruments, even binoculars are sufficient to reveal the Galilean moons of Jupiter, but not quite the rings of Saturn, for which you will require a small telescope at least to view them. You should note the banding on Jupiter’s disk, perhaps even the great red spot when orientated towards us. At Saturn (apart from the rings) you may also note Titan, Saturn’s largest moon, which resembles a bright, but obvious speck near to Saturn.
Have a little patience at the eyepiece when viewing Jupiter and Saturn as neither are particularly high above the horizon. The Moon passes below Jupiter and Saturn on the 24th and 25th respectively.
Already conspicuous to the eye in the early morning sky, Mars is now rapidly gaining in brightness, as it heads towards opposition in October and by the end of September will become the dominant presence in the late evening sky with its distinct orange hue. Look for Mars rising in the east when Jupiter and Saturn lie to the south. Telescopically Mars is improving through the eyepiece; just don’t expect it to be the size of Jupiter’s disk. Even when Mars reaches opposition, it will only appear half the size of Jupiter’s disk. If there are no obscuring Martian dust storms, you will be gazing at the surface itself. Apart from our moon, Mars is the only other body in the solar system where the surface is visible to typical amateur instruments. The waning moon passes below Mars on the 5th.
If you are an early riser look for brilliant Venus quite high in the eastern dawn sky, it can hardly be missed! On the morning of the 14th Venus resides below the open star cluster known as the ‘Beehive’ or M44, in Cancer, with a very slim moon visible above the cluster. The vista should make for a fine sight in binoculars.
The Autumnal Equinox
By astronomical convention autumn officially commences in the northern hemisphere on the date of the Autumnal Equinox, when from our perspective the Sun re-crosses the celestial equator and tracks southwards again, arcing ever lower in the sky. The date of the equinox this year falls on September 22nd and, like the spring equinox, this is when neither of Earth’s poles are inclined towards our nearest star so that all locations experience roughly equal hours of daylight and darkness. The northern hemisphere will then continue to tilt away from the Sun with evenings drawing in once again as we head through autumn and into winter.
The September Night Sky
With the resumption of astronomical twilight (true darkness) last month, the vast majority of stars are now visible before 10pm, making it somewhat easier for a casual observer to identify constellations in the night sky.
As twilight falls look for Arcturus, the brightest star in the summer sky over in the west. Overhead, lovely Vega in Lyra catches the eye, whilst low to the north, Capella in Auriga scintillates above the horizon. These are the three brightest stars north of the celestial equator visible from Britain. Each has a distinct hue: Arcturus appears orange, Capella, white, and Vega a lovely steely blue colour. High in the NW, look for the familiar saucepan outline of the ‘Plough’ – part of Ursa Major the Great Bear. The three stars marking the curved handle point down in the direction of Arcturus, located at the foot of Bootes, the herdsman. Note the delicate starry circlet of Corona Borealis, the Northern Crown situated to the upper left of Arcturus. Returning to the Plough, use the ‘pointer’ stars in the ‘bowl’ to locate the pole star, Polaris, in Ursa Minor by extending an imaginary line through them and continuing on a couple of hand spans to a relatively conspicuous, but solitary star.
Two large and sprawling groups occupy much of the SW aspect of the sky. The figure of Hercules, best identified by the ‘keystone’ asterism, stands upper left of Corona, whilst the vast and rather faint outline of Ophuichus, the Serpent Bearer, extends down from Hercules towards the SW horizon. As soon as twilight deepens in this direction look for the bright orange hue of Antares in Scorpius just above the horizon.
Should sky conditions be transparent, the asterism known as the ‘Teapot’, the most distinctive part of Sagittarius the Archer, may be traced above the S horizon. There are rich pickings in this part of the sky including numerous star fields, deep sky objects and the galactic centre. Jupiter and Saturn reside left of the ‘teapot’ asterism.
Following Sagittarius above the S horizon, Capricornus, the Sea Goat, heads an aquatically themed constellation parade which continues with Aquarius, the Water Bearer, low in the ESE and Pisces, the Fish, extending up from the east. If sky conditions are not ideal these groups can be hard to trace, in particular Pisces. However, for the time being, Mars glows fiercely at the foot of Pisces.
High overhead to the south and east, reside three bright stars. Vega, in the small geometric pattern of Lyra, is the most conspicuous, whilst to the east, Deneb sits at the tail end of Cygnus, the swan. Pearly white Altair resides midway up in the south in Aquila, the Eagle. These three stars form the asterism referred to as the ‘summer triangle’. Within the confines of the ‘summer triangle’ note the small stellar arrow shape of Sagitta, together with the close-knit group of Delphinus situated to its left. Both these small constellations do, with a little imagination, resemble the things they represent. Bizarrely Delphinus is sometimes known as ‘Job’s coffin’.
Over in the NE the great hero Perseus begins to climb away from the horizon, whilst above, the familiar ‘W’ pattern of Queen Cassiopeia holds court. Her daughter, Princess Andromeda, located to the lower right, is marked by a chain of stars extending towards the winged horse Pegasus, which occupies the mid regions of the E sky. Pegasus is best identified by ‘the great square’ an asterism comprising four stars that enclose a seemingly barren area of sky. The asterism serves as a useful signpost in locating numerous other stars, deep sky objects and constellations in the autumn sky, including the Andromeda galaxy, which is visible as a misty patch to the naked eye on dark moonless nights, upper left of the square. This is for next month however. Clear skies!
Mark Dawson,
Whitby and District Astronomical Society
WDAS usually meets in room H1, Caedmon College, Normanby campus (Whitby College). New members most welcome.
www.whitby-astronomers.com
email: spanton33@talktalk.net
.
