Fireball over Singapore

Fireball over Singapore December 31, 2016 © Cheng Joo Tan (https://500px.com/chengjoo) 30 sec. Nikon D90+Tokina 11-16mm @ 11mm

During this period the moon reaches its last quarter phase on Thursday January 19th. At this time the moon will be located 90 degrees west of the sun and will rise near midnight local standard time (LST). This weekend the waning gibbous moon will rise during the late evening hours and will make it difficult to view any meteor activity during the more active morning hours. The estimated total hourly meteor rates for evening observers this week is near 3 no matter your location. For morning observers the estimated total hourly rates should be near 6 no matter your location. Morning rates are reduced during this period due to lunar interference. 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 January 14/15. 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 7pm LST

Radiant Positions at 7pm Local Standard Time

Radiant Positions at Midnight Local Standard Time

Radiant Positions at Midnight Local Standard Time

Radiant Positions at 5am LST

Radiant Positions at 5am Local Standard Time

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

Details on each source will continue next week when observing conditions are much more favorable.

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
Anthelion (ANT) 08:28 (127) +19 30 01:00 2 -1 II
January xi Ursae Majorids (XUM) Jan 19 11:16 (169) +32 56 04:00 <1 – <1 IV
Dec. Leonis Minorids (DLM) Dec 20 12:12 (183) +20 63 05:00 <1 – <1 II
eta Corvids (ECV) Jan 23 12:40 (190) -22 69 06:00 <1 – <1 IV
nu Bootids (NBO) Jan 19 14:00 (206) +13 67 07:00 <1 – <1 IV
Canum Venaticids (CVN) Jan 15 14:00 (210) +38 56 07:00 <1 – <1 IV
gamma Ursae Minorids (GUM) Jan 20 15:04 (226) +71 31 09:00 <1 – <1 IV
lambda Bootids (LBO) Jan 17 16:00 (240) +45 41 09:00 <1 – <1 IV
xi Coronae Borealids (XCB) Jan 15 16:36 (249) +30 49 10:00 <1 – <1 IV

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