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During this period, the moon waxes from half illuminated to nearly full. This weekend the moon will set during the early morning hours, allowing several hours of good viewing prior to the start of dawn. As this period progresses, the waxing gibbous moon will begin to interfere with morning meteor observing as it sets approximately 45 minutes later with each passing night. By the end of this period the nearly full moon will lie above the horizon all night long, making meteor observing difficult at best. The estimated total hourly meteor rates for evening observers this week is near 3 as seen from mid-northern latitudes and 2 as seen from tropical southern locations (25S). For morning observers, the estimated total hourly rates should be near 17 as seen from mid-northern latitudes (45N) and 14 as seen from tropical southern locations (25S). Evening rates are reduced due to interfering 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 brighter 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 October 24/25. 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 far 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.

The first Andromedids (AND) of the year should become active during this period. These meteors are associated with the current predicted location of the remnants of comet 3D/Biela. They are not caused by the swarms that created the meteor storms of the 19th century. Those meteors are associated with the December phi Cassiopeiids and will be active in late November and early December. This source is active from October 26 through November 17 and reach maximum activity on November 6th. The radiant currently is located near 00:38 (010) +24. This position lies in southern Andromeda, 2 degrees west of the 4th magnitude star known as zeta Andromedae. This part of the sky is best placed near 22:00 LST, when the radiant lies highest above the horizon. Current rates would most likely be less than 1 no matter your location, With an entry velocity of 19 km/sec., the average Andromedid meteor would be of slow velocity.

The Southern Taurids (STA) are active from a large radiant centered at 02:54 (044) +12. This area of the sky is located in southeastern Aries, 2 degrees northeast of the 4th magnitude star known as mu Ceti. This source is best placed near midnight LST when it is located highest in the sky. Current hourly rates would be near 3 no matter your location. With an entry velocity of 27 km/sec., most activity from this source would possess medium-slow velocities.

The omicron Eridanids (OER) were discovered by Japanese observers using video data from SonotoCo in 2007-2008. The activity period ranges from October 16–November 24 with maximum activity occurring on November 5th. The radiant is currently located at 03:00 (045) -04, which places it in western Eridanus, 8 degrees south of the 3rd magnitude star known as Menkar (alpha Ceti). 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. Current hourly rates would be near 1 no matter your location. With an entry velocity of 29 km/sec., the average omicron Eridanid meteor would be of medium-slow velocity.

The Northern Taurids (NTA) are active from a large radiant centered at 03:08 (047) +21. This area of the sky is located in eastern Aries, 1-degree northwest of the 4th magnitude star known as Botein (delta Arietis). This source is best placed near midnight LST when it is located highest in the sky. Current hourly rates would be near 1 as seen from the northern hemisphere and less than 1 as seen from south of the equator. With an entry velocity of 27 km/sec., most activity from this source would possess medium-slow velocities.

The chi Taurids (CTA) were discovered by Dr. Peter Brown during his 7-year survey using the Canadian Meteor Orbit Radar (CMOR). This source is active from October 20 through November 17 with a maximum occurring near November 4th. Current rates would be less than 1 per hour no matter your location. The radiant is currently located at 03:32 (053) +25, which places it in northwestern Taurus, 3 degrees west of the naked eye open star cluster known as the Pleiades. This location is close to the source of the Northern Taurids so care must be taken to separate these meteors. These meteors may be seen all night long but the radiant is best placed near 0100 LST when it lies on the meridian and is located highest in the sky. With an entry velocity of 41 km/sec., the average chi Taurid meteor would be of medium velocity.

The Orionids (ORI) are active from a radiant located at 06:32 (098) +16. This area of the sky lies in southwestern Gemini, only 1 degree west of the 2nd magnitude star known as Alhena (gamma Geminorum). The radiant is best placed near 0400 LST, when it lies highest above the horizon. Hourly rates would be near 5 per as seen from the northern hemisphere and 4 as seen from south of the equator. With an entry velocity of 66 km/sec., most activity from this radiant would be of swift velocities.

The nu Eridanids (NUE) were co-discovered by Japanese observers using SonotoCo and Juergen Rendtel and Sirko Molau of the IMO. Activity from this long-period stream stretches from August 24 all the way to November 16. Maximum activity occurred on September 24th. The radiant currently lies at 07:06 (107) +12, which places it in northwestern Canis Minor, 5 degrees northwest of the 3rd magnitude star known as Gomeisa (beta Canis Minoris). This is close to the Orionid radiant and care must be taken to separate the two when observing. This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Current rates are expected to be less than 1 per hour during this period no matter your location. With an entry velocity of 67 km/sec., the average meteor from this source would be of swift velocity.

The epsilon Geminids (EGE) are active from September 30 through October 25 with maximum activity occurring on October 11. The radiant is currently located at 07:20 (110) +28, which places it in northern Gemini, 5 degrees west of the 1st magnitude star known as Pollux (beta Geminorum). This area of the sky is best placed in the sky during the last hour before dawn, when it lies highest above the horizon in a dark sky. Current rates would be less than 1 per hour no matter your location. With an entry velocity of 70 km/sec., most activity from this radiant would be of swift velocities.

The lambda Ursae Majorids (LUM) are a recent discovery by Željko Andreić and the Croatian Meteor Network team based on studying SonotaCo and CMN observations (SonotaCo 2007-2011, CMN 2007-2010). This weak shower is active from October 27-29 maximum activity occurring on the 28th. At maximum the radiant is located at 10:24 (156) +49. This position lies in a sparse area of central Ursa Major, between the 2nd magnitude star Merak (Beta Ursae Majoris) and 3rd magnitude Tania Borealis (Lambda Ursa Majoris). This area of the sky is best placed in the sky during the last hour before dawn, when it lies highest above the horizon in a dark sky. Rates at maximum would be less than 1 no matter your location. With an entry velocity of 61 km/sec., most activity from this radiant would be of swift speed.

The Leonis Minorids (LMI) are active from October 12-Nov 5 with maximum activity occurring on October 23rd. This radiant is currently located at 10:52 (163) +36, which places it in northeastern Leo Minor, 2 degrees north of the faint star known as 46 Leonis Minoris. The radiant is best placed just before dawn when it lies highest in a dark sky. This shower is better situated for observers situated in the northern hemisphere where the radiant rises far higher into the sky before the start of morning twilight. Current rates would be near 1 per hour as seen from the northern hemisphere and less than 1 as seen from south of the equator. At 62km/sec., the average Leonis Minorid is swift. From my personal experience this minor shower produces a high proportion of bright meteors.

As seen from mid-northern hemisphere (45N), sporadic morning rates would be near 10 per hour as seen from rural observing sites and 3 per hour during the evening hours. As seen from the tropical southern latitudes (25S), one would expect to see approximately 7 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 2 per hour. Locations between these two extremes would see activity between the listed figures. Evening rates are reduced due to moonlight.

The list below offers the information from above in tabular form. 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 Summer Time North-South
Andromedids (AND) Nov 06 00:38 (010) +24 19 23:00 <1 – <1 IV
Southern Taurids (STA) Nov 03 02:54 (044) +12 27 01:00 3 – 3 II
omicron Eridanids (OER) Nov 05 03:00 (045) -04 29 01:00 <1 – <1 IV
Northern Taurids (NTA) Nov 12 03:08 (047) +21 27 01:00 1- <1 II
chi Taurids (CTA) Nov 04 03:32 (053) +25 27 02:00 <1 – <1 IV
Orionids (ORI) Oct 21 06:32 (098) +16 66 05:00 5 – 4 I
nu Eridanids (NUE) Sep 24 07:06 (107) +12 67 06:00 <1 – <1 IV
epsilon Geminids (EGE) Oct 11 07:20 (110) +28 70 06:00 <1 – <1 II
lambda Ursae Majorids (LUM) Oct 28 10:24 (156) +49 62 09:00 <1 – <1 IV
Leonis Minorids (LMI) Oct 23 10:52 (163) +36 62 10:00 1 – <1 II

Zgodnie z:
Robert Lunsford


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