fireball
Fireball over Ralph, Saskatchewan, Canada – Sunday, Nov.8, 2015 – Probably AMS Event #3183-2015 © Bill Allen

During this period the moon reaches it’s first quarter phase on Monday November 7th. At this time the moon will be located 90 degrees east of the sun and will set near 2300 (11pm) local standard time (LST). As the week progresses the waxing gibbous moon will enter the morning sky and will begin to interfere with observations during the morning hours. The estimated total hourly meteor rates for evening observers this week is near 5 as seen from mid-northern latitudes (45N) and 4 as seen from tropical southern locations (25S). For morning observers the estimated total hourly rates should be near 25 as seen from mid-northern latitudes (45N) and 20 as seen from tropical southern locations (25S). Evening rates are reduced during this period due to moonlight. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brightest meteors will be visible from such locations.

The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning November 5/6 These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky, either due north or south along the meridian, depending on your latitude. It must be remembered that meteor activity is rarely seen at the radiant position. Rather they shoot outwards from the radiant so it is best to center your field of view so that the radiant lies at the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is a sporadic. Meteor activity is not seen from radiants that are located below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night.

Radiant Positions at 8pm LST

Radiant Positions at 8pm Local Standard Time

Radiant Positions at Midnight Local Standard Time

Radiant Positions at Midnight Local Standard Time

Radiant Positions at 4am LST

Radiant Positions at 4am Local Standard Time

These sources of meteoric activity are expected to be active this week.

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The Andromedids (AND) reach maximum activity on November 8th. At that time the radiant will be located near 01:32 (023) +29 . This position lies in western Triangulum, 4 degrees west of the 3rd magnitude star known as Mothallah (Alpha Trianguli). This part of the sky is best placed near 2200 (10pm) LST, when the radiant lies highest above the horizon. This is a famous shower that produced some brilliant displays during the 19th century. Since then the main orbit of the particles from comet 3D/Biela have moved away from the Earth. Still, remnants may be seen from October 26 through November 20. Current rates would most likely be near 1 per hour as seen from the northern hemisphere and less than 1 as seen south of the equator. With an entry velocity of 19 km/sec., the average Andromedid meteor would be of very slow velocity.

The Northern Taurids (NTA) are active from a large radiant located near 03:36 (054) +22. This position lies in western Taurus, just 2 degrees southwest of the bright open cluster of stars known as the Pleiades. Rates at this time should be near 5 per hour as seen from the northern hemisphere and 4 as seen south of the equator. Like its southern counterpart, these meteors may be seen all night long but the radiant is best placed near midnight LST when it lies on the meridian and is located highest in the sky.  With an entry velocity of 27 km/sec., the average Northern Taurid meteor would be of slow velocity.

The Southern Taurids (STA) are also active from a large radiant centered near 03:44 (056) +14. This position lies in western Taurus, 10 degrees south of the Pleiades. These meteors may be seen all night long but the radiant is best placed near midnight LST when it lies on the meridian and is located highest in the sky. Rates at this time should be near 4 per hour regardless of your location. With an entry velocity of 29 km/sec., the average Southern Taurid meteor would be of slow velocity.

The Orionids (ORI) are still active from a radiant located at 07:12 (108) +16. This area of the sky lies in southern Gemini, just west of the 4th magnitude star known as lambda Geminorum. This area of the sky is best placed near 0400 LST, when it lies highest above the horizon. Rates should be near 3 per hour no matter your location.  With an entry velocity of 67 km/sec., most activity from this radiant would be of swift speed.

The kappa Ursae Majorids (KUM) were discovered by cameras of the SonotaCo network in Japan during an outburst of activity on November 5, 2009. This radiant is active from November 2-9 with maximum activity occurring on the 5th. At maximum the radiant is located at 09:44 (146) +45. This position lies in southeastern Ursa Majoris, 7 degrees south of the 3rd magnitude star known as theta Ursae Majoris. Rates, even at maximum, are expected to be less than 1 regardless of your location. These meteors are best seen during the last hour before dawn when the radiant lies highest above the horizon in a dark sky. With an entry velocity of 62 km/sec., the average Kappa Ursae Majorid meteor would be of swift velocity.

The first Leonids (LEO) of the season should begin appearing this weekend from a radiant located at located at 09:48 (147) +25. This position lies in northwestern Leo, between the two fairly bright stars known as mu and epsilon Leonis. Current rates are expected to be near 2 shower members per hour during the late morning hours as seen from the northern hemisphere. Hourly rates from south of the equator would be near 1. Maximum is predicted to occur on November 17.  The Leonid radiant is best placed during the last hour before morning twilight when the radiant lies highest in a dark sky. Leonids may be seen from the southern hemisphere but the viewing conditions are not quite as favorable as those north of the equator. With an entry velocity of 70 km/sec., most activity from this radiant would be of swift speed with numerous persistent trains on the brighter meteors.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately 11 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 3 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 8 per hour as seen from rural observing sites and 2 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Evening rates are reduced due to lunar interference.

The table below presents a list of radiants that are expected to be active this week. Rates and positions are exact for Saturday night/Sunday morning except where noted in the shower descriptions.

SHOWER DATE OF MAXIMUM ACTIVITY CELESTIAL POSITION ENTRY VELOCITY CULMINATION HOURLY RATE CLASS
RA (RA in Deg.) DEC Km/Sec Local Standard Time North-South
Andromedids (AND) Nov 08 01:32 (023) +29 19 22:00 1 – <1 III
Northern Taurids (NTA) Nov 11 03:36 (054) +22 27 00:00 5 – 4 II
Southern Taurids (STA) Oct 10 03:44 (056) +14 29 00:00 4 – 4 II
Orionids (ORI) Oct 22 07:12 (108) +16 67 04:00 3 – 3 I
kappa Ursa Majorids (KUM) Nov 05 09:44 (146) +45 62 06:00 <1 – <1 IV
Leonids (LEO) Nov 17 09:48 (147) +25 70 06:00 2 – 1 III

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