Upcoming Meteor Event Happening This February 2023
During this period, the moon reaches its last
quarter phase on Monday, February 13th. At that time the half-illuminated moon
will lie 90 degrees west of the sun and will rise between 0100 and 0200
local standard time (LST). As the week progresses the moon will rise later each
night providing a larger window of opportunity to view the sky under dark
conditions. The estimated total hourly rates for evening observers this week
should be near 3 as seen from mid-northern latitudes (45N) and 5 as seen from
tropical southern locations (25S) For morning observers, the estimated total
hourly rates should be near 6 as seen from mid-northern latitudes (45N) and 12
as seen from tropical southern locations (25S). Morning rates are reduced by
moonlight during this period. The actual rates seen 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 February 11/12. These positions do not change greatly from 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. I have also included charts of
the sky that display the radiant positions for evening, midnight, and morning.
The centre of each chart is the sky directly overhead at the appropriate hour.
These charts are oriented for facing south but can be used in any direction by
rotating the charts to the desired direction. 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 centre your field of view so that the radiant lies at
the edge and not the centre. 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 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 large Anthelion (ANT) is
currently centred at 10:24 (156) +10. This position lies in western Leo, 3
degrees southeast of the 1st magnitude star known as Regulus (alpha Leonis).
Due to the large size of this radiant, these meteors may also be seen from
eastern Cancer as well as Leo. This radiant is best placed near 01:00 LST when
it lies on the meridian and is highest in the northern sky. Rates at this time
should be near 2 per hour as seen from the northern hemisphere and 1 per hour from the south of the equator. With an entry velocity of 30 km/sec., the
average Anthelion meteor would be of slow velocity.
The gamma Crucids (GCR) were
discovered in 2021 by the CAMS system of meteor cameras managed by Dr Peter
Jenniskens. This shower is active from February 11-15 with a peak on the 14th. At maximum,
the radiant is located at 12:32 (193) -56. This area of the sky is located in
northern Crux, only 1 degree north of the 2nd magnitude
star known as Gacrux (gamma Crucis). Observers in the Southern Hemisphere are
greatly favoured in seeing these meteors as the radiant does not clear the
horizon for the northern two-thirds of the Northern Hemisphere. 40 of these
meteors were captured in 2021. It will be interesting to see what occurs this
year as last year’s observations were hampered by a full moon. These meteors
are best seen near 03:00 LST when the radiant lies highest above the southern horizon.
With an entry velocity of 56 km/sec., the average meteor from this source would
be swift.
The alpha Centaurids (ACE) are
active from January 31-February 20, with maximum activity occurring on February
8th. The radiant is currently located at 14:19 (215) -59. This position lies in
southeastern Centaurus, 2 degrees northeast of the 1st magnitude
star known as Hadar (beta Centauri). Due to the southern declination of this
radiant, these meteors are not well seen in the northern hemisphere. Current
hourly rates are expected to be less than 1 as seen from the Northern
Hemisphere and near 1 as seen from south of the equator. These meteors are best
seen near 05:00 LST when the radiant lies highest above the southern horizon.
At 56 km/sec. the alpha Centaurids would produce mostly swift meteors.
As seen from the
mid-northern hemisphere (45N) one would expect to see approximately 4 sporadic meteors
per hour during the last hour before dawn as seen from rural observing sites.
Evening rates would be near 2 per hour. As seen from the tropical southern
latitudes (25S), morning rates would be near 10 per hour as seen from rural
observing sites and 4 per hour during the evening hours. Morning rates are
slightly reduced due to moonlight.
You can keep track
of the activity of these meteor showers as well as those beyond the limits of
visual observation by visiting the NASA Meteor Shower Portal. You can move the sky
globe to see different areas of the sky. Coloured dots indicate shower meteors
while white dots indicate sporadic (random) activity. The large orange disk
indicates the position of the sun so little activity will be seen in that area
of the sky.
The list below
offers the information in tabular form of the showers that I feel are within
reach of the visual observer to discern. Hourly rates are often less than 1 but by noting parameters such as the radiant distance and the elevation of each
meteor, one can compute the probability of shower association. Most showers discovered
by video means have rates less than 1 per night away
from the maximum, so the showers listed in these outlooks are not as weak as they
seem. Rates and positions are exact for Saturday night/Sunday morning except
where noted in the shower descriptions.
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