- Posts: 733
- Thank you received: 989
May 2010 Observing Guide
- Neill
- Topic Author
- Offline
- Moderator
-
14 years 7 months ago #84649
by Neill
May 2010 Observing Guide was created by Neill
OBSERVING GUIDE
(Please note all times are ST unless otherwise stated and are based on an observing location of Belfast and covers the month of May)
The Sun
At the start of the month, the Sun rises at 05:45 and sets at 21:00. By the end of the month, it rises at 05:00 and sets at 21:50.
The Planets
Mercury is at inferior conjunction on the 28th of April and despite being at greatest western elongation on the 26th, it is poorly placed for observation this month.
Venus is now a prominent evening object at mag -3.9. At the start of the month, it sets at 23:40 and by month’s end, it sets at 00:35. On the evening of the 8th, it passes close to NGC 1746 and on the evening of the 21st, it passes within less than a degree of M35 to the North of the cluster.
Mars is past its best but is still well placed for observation as an evening object. During the whole month, it rises during daylight hours and by month’s end, sets at 02:10. It does however fade during the month from mag +0.7 to mag +1.1. It starts the month in Cancer, but continues its easterly motion and moves in Leo, lying three degrees to the West of Regulus (Alpha Leonis, mag +1.4) at the end of the month.
Jupiter moves away from the sun’s glare and by month’s end; it rises at 02:50, roughly two hours before sunrise. It is in Pisces and brightens during the month from mag -2.1 to mag -2.3. It is at conjunction with Uranus in the first week of June and by month’s end, the gap between the planets is around one degree with Uranus to the East of Jupiter.
Saturn is well placed for observation as an evening object in Virgo. During the month, it rises during daylight hours and by month’s end, sets at 03:10. It fades from mag +0.8 to mag +1.0 during the month.
Uranus moves away from the sun’s glare and by month’s end; it rises at 02:50, roughly two hours before sunrise. It is in Pisces and maintains its brightness during the month at mag +5.9. It is at conjunction with Jupiter in the first week of June (see above).
Neptune also is moving away from the sun and by month’s end; it rises at 02:00. It is in Aquarius and maintains its brightness at mag +7.9 during the month.
The Moon
In May, the last quarter moon is on the 6th with the new moon on the 14th. The first quarter moon is on the 20th with the full moon on the 27th. On the last few nights of the month, look out for the moon illusion effect with the full moon rising on the 27th at around 21:55 in Scorpius low on the SE horizon. The waning gibbous moon then rises at around 22:55 on the 28th and at around 23:45 on the 29th close to the horizon.
On the morning of the 1st, a 93% illuminated waning gibbous moon lies four degrees to the East of Antares (Alpha Scorpii, mag +0.9) at around 02:00.
On the morning of the 9th, a 23% illuminated waning crescent moon lies eight degrees to the North-West of Jupiter at 05:00 with Uranus to the East of Jupiter.
On the evening of the 15th, a 4% illuminated waxing crescent moon lies seven degrees to the West of Venus at 22:00. At the same time, NGC 1746 lies one degree from the moon.
On the evening of the 16th, a 10% illuminated waxing crescent moon lies six degrees to the East of Venus at 23:00. At the same time, M35 lies one degree to the North of the moon.
On the evening of the 19th, a 38% illuminated waxing gibbous moon lies four degrees to the West of M67 at around midnight.
On the evening of the 20th, the first quarter moon lies seven degrees to the South of Regulus (Alpha Leonis, mag +1.4) at around midnight.
On the evening of the 24th, a 89% illuminated waxing gibbous moon lies six degrees to the South of Spica (Alpha Virginis, mag +1.0) at around midnight.
On the evening of the 27th, the full moon lies three degrees to the West of Antares (Alpha Scorpii, mag +0.9) at around midnight.
On the morning of the 28th, the full moon occults Al Niyat (Sigma Scorpii, mag +2.9). The star disappears behind the lower-left edge of the moon around 02:10 and reappears around 03:10 from behind the lower-right edge.
Meteors
The ZHR or Zenithal Hourly Rate is the number of meteors an observer would see in one hour under a clear, dark sky with a limiting apparent magnitude of 6.5 and if the radiant of the shower were in the zenith. The rate that can effectively be seen is nearly always lower and decreases as the radiant is closer to the horizon. The Zenith is the overhead point in the sky for an observer. The radiant is the point in the sky, from which (to a planetary observer) meteors appear to originate, i.e. the Perseids, for example, are meteors which appear to come from a point within the constellation of Perseus. A fireball is defined by the International Astronomical Union as a meteor brighter than any of the planets, i.e. magnitude -4 or brighter. The International Meteor Organisation alternatively defines it as a meteor which would have a magnitude of -3 or brighter at the zenith.
There are two showers this month. The first shower is the Eta Aquarids which peaks on the morning of the 6th. The ZHR predictions for this shower vary between 40 and 85. These are typically fast, bright meteors and are of a similar speed to the Perseids. Some will leave persistent trains. However it is not a well placed shower for us. The radiant only rises at 05:00 in the morning twilight and there is lunar interference from the last quarter moon in Capricornus.
The second shower this month is a minor one. They are the Eta Lyrids, peaking on the 9th with a ZHR of 3. The radiant is visible once darkness falls and there is no lunar interference with this shower.
Asteroids
There are several asteroids on view in May. 1 Ceres is visible in the morning sky in Sagittarius. It brightens to mag +7.5 by month’s end and moves in a westerly direction. At the start of the month, it lies between Mu Sagittarii (mag +3.9) and Lambda Sagittarii (mag +2.
, by month’s end, it lies near to M8. It is at opposition next month.
2 Pallas travels in a westerly direction during May and fades to mag +9.0 during the month. It moves into Corona Borealis from Serpens Caput during the second half of the month, passing within two degrees of Alphecca (Alpha Coronae Borealis, mag +2.2).
4 Vesta travels in an easterly direction during May and fades to mag +7.7 during the month. It is in Leo and passes between Mu Leonis (mag +3.9) and Algeiba (Gamma Leonis, mag +2.6) around the 23rd. Detailed finder charts for all three are available at the RASNZ website whose address is below.
Comets
Comet 81P/Wild 2 can be observed in Virgo during May. It should be visible once darkness falls throughout the month. It is currently around mag +9, but is predicted to slowly fade from June onwards. It lies near to Iota Virginis (mag +4.1) throughout the month, to the West of the star at a distance of around three degrees.
Comet C/2009 K5 (McNaught) is predicted to be around mag +9 in May. It should be visible once darkness falls throughout the month and starts the month in Cepheus; moving into Camelopardalis by month’s end.
Comet C/2009 R1 (McNaught) is predicted to be around mag +9 in May. It is only visible in the second half of the month and will be at its best at month’s end. It is visible from around 03:00, but may get lost quickly in the morning twilight. At mid-month, it lies inside the square of Pegasus, near to Algenib (Gamma Pegasi, mag +2. – the bottom left star in the square. It moves in a Northerly direction and by month’s end, lies beneath Mirach (Beta Andromedae, mag +2.1).
Deep Sky
On the deep sky front this month, galaxies M81 and M82 can be observed in Ursa Major. In Leo, we have several galaxies on view including The Leo Triplet - M65, M66 and NGC 3628. M95, M96 and M105 can also be observed in Leo. The place to really find galaxies is in Virgo. The Virgo Super Cluster can be found here with numerous galaxies on view. Also in Virgo, M104 - the Sombrero Galaxy can be found. In Coma Berenices, there is M64 - the Black-Eye Galaxy. Also check out the constellation Canes Venatici with the globular cluster - M3 and several galaxies including M51 - the Whirlpool Galaxy and M63 - the Sunflower Galaxy. In Hercules, two globular clusters – M92 and the excellent M13 can be observed and in Lyra – M57 – The Ring Nebula can be observed. Finally there are some excellent open clusters in Cancer - M44 – The Beehive Cluster and M67.
General Notes
Always keep an eye out for Aurorae. Watch out for NLCs - Noctilucent Clouds during May. They are also known as Polar Mesospheric Clouds as they are thought to be due to water ice particles up in the mesosphere. They are mostly visible between the Northern latitudes of 50 to 65 degrees, however sightings have been made as far South as Iran – 38 degrees. Look to the North for a white/silvery glow. They can sometimes be faint, sometimes bright. Other interesting naked eye phenomena to look out for include the Zodiacal Light and the Gegenschein. Both are caused by sunlight reflecting off dust particles which are present in the solar system.
The Zodiacal Light can be seen in the West after evening twilight has disappeared or in the East before the morning twilight. The best time of year to see the phenomenon is late-Feb to early-April in the evening sky and September/October in the morning sky - it's then that the ecliptic, along which the cone of the zodiacal light lies, is steepest in our skies. The Gegenschein can be seen in the area of the sky opposite the sun. To view either, you must get yourself to a very dark site to cut out the light pollution. When trying to observe either of these phenomena, it is best to do so when the moon is below the horizon.
Clear Skies
Neill McKeown
Information Sources Used and Links
www.skyviewcafe.com - Used for the Sun and Planets section. Also partly used for the Moon Section
Sky at Night Magazine Observing Guide and CD
www.aerith.net and cometchasing.skyhound.com – Used for the Comet Section for information and finder charts
www.ast.cam.ac.uk/%7Ejds/ - BAA and SPA Comet page
kometen.fg-vds.de/fgk_hpe.htm - German Comet page
www.rasnz.org.nz – Royal Astronomical Society of New Zealand website – good for asteroids
BAA Handbook
Stardust Magazine
Sky Guide 2010 – South Dublin Astronomical Society
Philip’s Stargazing 2010
Patrick Moore’s 2010 Yearbook of Astronomy
www.heavens-above.com – For the latest ISS passes, Iridium Flares and Shuttle launches
www.irishastronomy.org – Irish Federation of Astronomy Societies Website
www.stronge.org.uk – Excellent weather site including Space Weather
www.irishastro.org.uk – Irish Astronomical Association website
www.eaas.co.uk – Northern Ireland Amateur Astronomy Society
(Please note all times are ST unless otherwise stated and are based on an observing location of Belfast and covers the month of May)
The Sun
At the start of the month, the Sun rises at 05:45 and sets at 21:00. By the end of the month, it rises at 05:00 and sets at 21:50.
The Planets
Mercury is at inferior conjunction on the 28th of April and despite being at greatest western elongation on the 26th, it is poorly placed for observation this month.
Venus is now a prominent evening object at mag -3.9. At the start of the month, it sets at 23:40 and by month’s end, it sets at 00:35. On the evening of the 8th, it passes close to NGC 1746 and on the evening of the 21st, it passes within less than a degree of M35 to the North of the cluster.
Mars is past its best but is still well placed for observation as an evening object. During the whole month, it rises during daylight hours and by month’s end, sets at 02:10. It does however fade during the month from mag +0.7 to mag +1.1. It starts the month in Cancer, but continues its easterly motion and moves in Leo, lying three degrees to the West of Regulus (Alpha Leonis, mag +1.4) at the end of the month.
Jupiter moves away from the sun’s glare and by month’s end; it rises at 02:50, roughly two hours before sunrise. It is in Pisces and brightens during the month from mag -2.1 to mag -2.3. It is at conjunction with Uranus in the first week of June and by month’s end, the gap between the planets is around one degree with Uranus to the East of Jupiter.
Saturn is well placed for observation as an evening object in Virgo. During the month, it rises during daylight hours and by month’s end, sets at 03:10. It fades from mag +0.8 to mag +1.0 during the month.
Uranus moves away from the sun’s glare and by month’s end; it rises at 02:50, roughly two hours before sunrise. It is in Pisces and maintains its brightness during the month at mag +5.9. It is at conjunction with Jupiter in the first week of June (see above).
Neptune also is moving away from the sun and by month’s end; it rises at 02:00. It is in Aquarius and maintains its brightness at mag +7.9 during the month.
The Moon
In May, the last quarter moon is on the 6th with the new moon on the 14th. The first quarter moon is on the 20th with the full moon on the 27th. On the last few nights of the month, look out for the moon illusion effect with the full moon rising on the 27th at around 21:55 in Scorpius low on the SE horizon. The waning gibbous moon then rises at around 22:55 on the 28th and at around 23:45 on the 29th close to the horizon.
On the morning of the 1st, a 93% illuminated waning gibbous moon lies four degrees to the East of Antares (Alpha Scorpii, mag +0.9) at around 02:00.
On the morning of the 9th, a 23% illuminated waning crescent moon lies eight degrees to the North-West of Jupiter at 05:00 with Uranus to the East of Jupiter.
On the evening of the 15th, a 4% illuminated waxing crescent moon lies seven degrees to the West of Venus at 22:00. At the same time, NGC 1746 lies one degree from the moon.
On the evening of the 16th, a 10% illuminated waxing crescent moon lies six degrees to the East of Venus at 23:00. At the same time, M35 lies one degree to the North of the moon.
On the evening of the 19th, a 38% illuminated waxing gibbous moon lies four degrees to the West of M67 at around midnight.
On the evening of the 20th, the first quarter moon lies seven degrees to the South of Regulus (Alpha Leonis, mag +1.4) at around midnight.
On the evening of the 24th, a 89% illuminated waxing gibbous moon lies six degrees to the South of Spica (Alpha Virginis, mag +1.0) at around midnight.
On the evening of the 27th, the full moon lies three degrees to the West of Antares (Alpha Scorpii, mag +0.9) at around midnight.
On the morning of the 28th, the full moon occults Al Niyat (Sigma Scorpii, mag +2.9). The star disappears behind the lower-left edge of the moon around 02:10 and reappears around 03:10 from behind the lower-right edge.
Meteors
The ZHR or Zenithal Hourly Rate is the number of meteors an observer would see in one hour under a clear, dark sky with a limiting apparent magnitude of 6.5 and if the radiant of the shower were in the zenith. The rate that can effectively be seen is nearly always lower and decreases as the radiant is closer to the horizon. The Zenith is the overhead point in the sky for an observer. The radiant is the point in the sky, from which (to a planetary observer) meteors appear to originate, i.e. the Perseids, for example, are meteors which appear to come from a point within the constellation of Perseus. A fireball is defined by the International Astronomical Union as a meteor brighter than any of the planets, i.e. magnitude -4 or brighter. The International Meteor Organisation alternatively defines it as a meteor which would have a magnitude of -3 or brighter at the zenith.
There are two showers this month. The first shower is the Eta Aquarids which peaks on the morning of the 6th. The ZHR predictions for this shower vary between 40 and 85. These are typically fast, bright meteors and are of a similar speed to the Perseids. Some will leave persistent trains. However it is not a well placed shower for us. The radiant only rises at 05:00 in the morning twilight and there is lunar interference from the last quarter moon in Capricornus.
The second shower this month is a minor one. They are the Eta Lyrids, peaking on the 9th with a ZHR of 3. The radiant is visible once darkness falls and there is no lunar interference with this shower.
Asteroids
There are several asteroids on view in May. 1 Ceres is visible in the morning sky in Sagittarius. It brightens to mag +7.5 by month’s end and moves in a westerly direction. At the start of the month, it lies between Mu Sagittarii (mag +3.9) and Lambda Sagittarii (mag +2.
, by month’s end, it lies near to M8. It is at opposition next month.2 Pallas travels in a westerly direction during May and fades to mag +9.0 during the month. It moves into Corona Borealis from Serpens Caput during the second half of the month, passing within two degrees of Alphecca (Alpha Coronae Borealis, mag +2.2).
4 Vesta travels in an easterly direction during May and fades to mag +7.7 during the month. It is in Leo and passes between Mu Leonis (mag +3.9) and Algeiba (Gamma Leonis, mag +2.6) around the 23rd. Detailed finder charts for all three are available at the RASNZ website whose address is below.
Comets
Comet 81P/Wild 2 can be observed in Virgo during May. It should be visible once darkness falls throughout the month. It is currently around mag +9, but is predicted to slowly fade from June onwards. It lies near to Iota Virginis (mag +4.1) throughout the month, to the West of the star at a distance of around three degrees.
Comet C/2009 K5 (McNaught) is predicted to be around mag +9 in May. It should be visible once darkness falls throughout the month and starts the month in Cepheus; moving into Camelopardalis by month’s end.
Comet C/2009 R1 (McNaught) is predicted to be around mag +9 in May. It is only visible in the second half of the month and will be at its best at month’s end. It is visible from around 03:00, but may get lost quickly in the morning twilight. At mid-month, it lies inside the square of Pegasus, near to Algenib (Gamma Pegasi, mag +2.
– the bottom left star in the square. It moves in a Northerly direction and by month’s end, lies beneath Mirach (Beta Andromedae, mag +2.1).Deep Sky
On the deep sky front this month, galaxies M81 and M82 can be observed in Ursa Major. In Leo, we have several galaxies on view including The Leo Triplet - M65, M66 and NGC 3628. M95, M96 and M105 can also be observed in Leo. The place to really find galaxies is in Virgo. The Virgo Super Cluster can be found here with numerous galaxies on view. Also in Virgo, M104 - the Sombrero Galaxy can be found. In Coma Berenices, there is M64 - the Black-Eye Galaxy. Also check out the constellation Canes Venatici with the globular cluster - M3 and several galaxies including M51 - the Whirlpool Galaxy and M63 - the Sunflower Galaxy. In Hercules, two globular clusters – M92 and the excellent M13 can be observed and in Lyra – M57 – The Ring Nebula can be observed. Finally there are some excellent open clusters in Cancer - M44 – The Beehive Cluster and M67.
General Notes
Always keep an eye out for Aurorae. Watch out for NLCs - Noctilucent Clouds during May. They are also known as Polar Mesospheric Clouds as they are thought to be due to water ice particles up in the mesosphere. They are mostly visible between the Northern latitudes of 50 to 65 degrees, however sightings have been made as far South as Iran – 38 degrees. Look to the North for a white/silvery glow. They can sometimes be faint, sometimes bright. Other interesting naked eye phenomena to look out for include the Zodiacal Light and the Gegenschein. Both are caused by sunlight reflecting off dust particles which are present in the solar system.
The Zodiacal Light can be seen in the West after evening twilight has disappeared or in the East before the morning twilight. The best time of year to see the phenomenon is late-Feb to early-April in the evening sky and September/October in the morning sky - it's then that the ecliptic, along which the cone of the zodiacal light lies, is steepest in our skies. The Gegenschein can be seen in the area of the sky opposite the sun. To view either, you must get yourself to a very dark site to cut out the light pollution. When trying to observe either of these phenomena, it is best to do so when the moon is below the horizon.
Clear Skies
Neill McKeown
Information Sources Used and Links
www.skyviewcafe.com - Used for the Sun and Planets section. Also partly used for the Moon Section
Sky at Night Magazine Observing Guide and CD
www.aerith.net and cometchasing.skyhound.com – Used for the Comet Section for information and finder charts
www.ast.cam.ac.uk/%7Ejds/ - BAA and SPA Comet page
kometen.fg-vds.de/fgk_hpe.htm - German Comet page
www.rasnz.org.nz – Royal Astronomical Society of New Zealand website – good for asteroids
BAA Handbook
Stardust Magazine
Sky Guide 2010 – South Dublin Astronomical Society
Philip’s Stargazing 2010
Patrick Moore’s 2010 Yearbook of Astronomy
www.heavens-above.com – For the latest ISS passes, Iridium Flares and Shuttle launches
www.irishastronomy.org – Irish Federation of Astronomy Societies Website
www.stronge.org.uk – Excellent weather site including Space Weather
www.irishastro.org.uk – Irish Astronomical Association website
www.eaas.co.uk – Northern Ireland Amateur Astronomy Society
Please Log in or Create an account to join the conversation.
- phoenix
- Offline
- Red Giant
-
Moderators: Neill
Time to create page: 0.107 seconds
