Sirko Molau captured this horizontal fireball with his AllSky7 Camera System at 19:48 UT (21:48 CEST) on April 17, 2022, from Brandenburg, Germany. For more information on this fireball visit: https://fireball.amsmeteors.org/members/imo_view/event/2022/2411 ©Sirko Molau

During this period, the moon reaches its full phase on Wednesday July 13th. At that time the moon is located opposite the sun and remains above the horizon all night long. This weekend the waxing gibbous moon will set during the early morning hours, allowing a few hours of observing time under dark skies. The estimated total hourly rates for evening observers this week should be near 2 as seen from mid-northern latitudes (45N) and 2 as seen from tropical southern locations (25S) For morning observers, the estimated total hourly rates should be near 12 as seen from mid-northern latitudes (45N) and 13 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 July 8/9. 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. I have also included charts of the sky that display the radiant positions for evening, midnight, and morning. The center of each chart is the sky directly overhead at the appropriate hour. These charts are oriented for facing south but can be used for 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 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 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.

 

Radiant Positions at 23:00 LST

Radiant Positions at 23:00 Local Summer Time

Radiant Positions at 01:00 LST

Radiant Positions at 01:00 Local Summer Time

Radiant Positions at 03:00 LST

Radiant Positions at 03:00 Local Summer Time

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

.

The alpha Capricornids (CAP) are active from July 7 through August 15, peaking on July 31st. The radiant is currently located at 19:16 (289) -15. This position lies in northeastern Sagittarius, 3 degrees northwest of the 4th magnitude star known as rho1 Sagittarii. Current rates are expected to be less than 1 per hour as seen from the Northern Hemisphere and near 1 per hour as seen from south of the equator. These meteors are best seen near 0100 local Summer Time (LST), when the radiant lies highest in the sky. With an entry velocity of 26 km/sec., the average meteor from this source would be of slow velocity.

The large Anthelion (ANT) is currently centered at 20:00 (300) -20. This position lies in northeastern Sagittarius, 8 degrees southwest of the 3rd magnitude star known as Dabih (beta Capricorni Aa). This radiant is best placed near 01:00 LST when it lies on the meridian and is highest in the sky. Rates at this time should be near 1 per hour as seen from the Northern Hemisphere and 2 as seen from south of the equator. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of slow velocity.

The July Pegasids (JPE) are active from July 4th through August 8th with maximum activity occurring on July 11th. The radiant is currently located at 22:40 (340) +15. This area of the sky is located in southern Pegasus, 4 degrees west of the 2nd magnitude star known as Markab (alpha Pegasi). This radiant is best placed near 0500 LST, when it lies on the meridian and is located highest in the sky. Rates are expected to be near 1 per hour this week no matter your location. With an entry velocity of 64 km/sec., the average meteor from this source would be of swift velocity.

The first eta Eridanids (ERI) of the season may be seen this week from a radiant near 01:16 (019) -23. This position lies in southern Cetus, 8 degrees southwest of the 4th magnitude star known as nu Ceti. This source is active until September 10th, with maximum activity occurring on August 6th. Current rates would be less than 1 per hour no matter your location. These meteors are best seen during the last dark hour prior to dawn when the radiant lies highest above the horizon in a dark sky. It should be noted that this radiant rises during twilight for the northern half of the Northern Hemisphere. Therefore, these meteors are not visible until later in the activity period when nights become longer for the Northern Hemisphere. With an entry velocity of 64 km/sec., the average meteor from this source would be of swift speed.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately 8 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 1 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 1 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Evening rates are reduced during this period 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
alpha Capricornids (CAP) Jul 30 19:16 (289) -15 23 01:00 <1 – 1 II
Anthelion (ANT) 20:00 (300) -19 30 02:00 1 – 2 II
July Pegasids (JPE) Jul 11 22:40 (340) +15 61 05:00 1 – 1 II
eta Eridanids (ERI) Aug 06 01:16 (019) -23 64 08:00 <1 – <1 II

Tags:

Leave a Reply

Your email address will not be published. Required fields are marked *