February offers the meteor observer in the northern hemisphere a couple of weak showers plus falling sporadic rates. This may not seem too exiting but you never know when surprises are in store. An errant earthgrazer from the Centaurid complex may shoot northward. Better yet, a bright fireball may light up the sky. February is the start of the fireball season, when an abundance of fireballs seem to occur. This lasts well into April and seems to occur mostly during the early evening hours.
Observers in the southern hemisphere are treated to the Alpha Centaurid peak on the 8th plus the entire Centaurid complex of radiants is active all month long. This is reminiscent of the summer activity seen from the northern hemisphere in the Milky Way constellations of Perseus and Auriga during August and September. Sporadic rates also peak this month south of the equator this month adding to the celestial show.
During this period the moon reaches its first quarter phase on Thursday February 6th. At this time the moon will lie 90 degrees east of the sun and will set near 0100 local standard time (LST) as seen from mid-northern latitudes. This weekend the waxing crescent moon will set during the early evening hours and will not pose any problems for viewing during the more active morning hours. The estimated total hourly meteor rates for evening observers this week is near 3 for observers situated at mid-northern latitudes and 5 for observers viewing from the southern tropics (latitude 25 S.). For morning observers the estimated total hourly rates should be near 9 for observers situated at mid-northern latitudes and 14 for observers viewing from the southern tropics. 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 February 1/2. 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.
The following sources of meteoric activity are expected to be active this week:
The center of the large Anthelion (ANT) radiant is currently located at 09:44 (146) +12. This position lies in western Leo, 5 degrees west of the 1st magnitude star known as Regulus (Alpha Leonis). Due to the large size of this radiant, Anthelion activity may also appear from Cancer, Sextans, northwestern Hydra as well as Leo. This radiant is best placed near 0100 LST, when it lies on the meridian and is located highest in the sky. Rates at this time should be near 1 no matter your location. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of slow velocity.
The February Epsilon Virginids (FEV) is a weak shower active only from February 3-6, with maximum activity occurring on the 4th. At peak activity the radiant located at 13:24 (201) +11. This position is located in northern Virgo , 5 degrees east of the 3rd magnitude star known as Vindemiatrix (Epsilon Virginis). These meteors are best seen near 0400 LST, when the radiant lies highest above the horizon in a dark sky. Rates would mostly likely be less than one shower member per hour, no matter your location. At 65 km/sec. the February Epsilon Virginids would produce mostly swift meteors. It is possible that these meteors are a continuation of the Coma Berenicids which were active In December and January.
The Alpha Centaurids (ACE) are active from January 28 though February 21, with maximum activity occurring on February 8. The radiant is currently located at 13:32 (203) -57. This position lies in southeastern Centaurus between the bright stars Mimosa (Beta Crucis) and Epsilon Centauri. Due to the southern declination of this radiant, these meteors are not well seen in the northern hemisphere. Current rates would be near 1 per hour as seen from the southern hemisphere and less than 1 from the northern hemisphere. These meteors are best seen near 0400 LST when the radiant lies highest above the horizon. At 56 km/sec. the Alpha Centaurids would produce mostly swift meteors.
The February Eta Draconids (FED) are active from January 29 through February 9, with maximum activity occurring on February 4. . This shower was discovered by Dr. Peter Jenniskens and Peter Gural using data from a “CAMS” network located in northern California. The current location of this radiant is estimated to be 15:56 (239) +62. This area of the sky is located in central Draco, 5 degrees east of the 3rd magnitude star Eta Draconis. These meteors are best seen near 0400 LST when the radiant lies highest above the horizon. Due to the high northern declination (celestial latitude) these meteors are poorly seen from the southern hemisphere. Rates less than 1 are expected this week. At 36 km/sec. the February Eta Draconids would produce mostly medium velocity meteors.
The Alpha Coronae Borealids (ACB) were discovered by John Greaves using data from SonotaCo Network Japan. These meteors are best seen from January 27 through February 5 with maximum activity occurring on January 28th. The radiant is currently located near 16:00 (240) +22. This position lies in northern Serpens Caput between the two bright stars Alphecca (Alpha Coronae Borealis) and Kornephoros (Beta Herculis. These meteors are best seen near 0400 LST when the radiant lies highest above the horizon. Rates this week woulf be near 1 meteor per hour as seen from the northern hemisphere and less than 1 as seen from south of the equator. At 58 km/sec. the Alpha Coronae Borealids would produce mostly swift meteors.
As seen from the mid-northern hemisphere (45N) 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 3 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 12 per hour as seen from rural observing sites and 4 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures.
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|
|Anthelions (ANT)||–||09:44 (146) +12||29||01:00||1 – 1||II|
|February Epsilon Virginids (FEV)||Feb 04||13:24 (201) +11||65||04:00||<1 – <1||IV|
|Alpha Centaurids (ACE)||Feb 08||13:32 (203) -57||56||05:00||<1 – 1||II|
|February Eta Draconids (FED)||Feb 04||15:56 (239) +62||36||07:00||<1 – <1||IV|
|Alpha Coronae Borealids (ACB)||Jan 28||16:00 (240) +22||58||07:00||1 – <1||IV|