Ryan Conner captured this brilliant fireball using his AllSky Camera System on May 1, 2024, at 3:46 EDT (7:27 UT) from North Royalton, Ohio USA. The secondary streak is an artifact due to the extreme brightness of this fireball. ©Ryan Conner

During this period, the moon reaches its first quarter phase on Thursday October 10th. At that time the moon will lie 90 degrees east of the sun and will set near 22:00 local summer time (LST) on that night. This weekend the waxing crescent moon will set during the early evening hours and will set long before the more active morning hours arrive. The estimated total hourly rates for evening observers this weekend should be near 3 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 13 as seen from mid-northern latitudes (45N) and 10 as seen from tropical southern locations (25S). 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 October 5/6. 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. Radiants that rise after midnight will not reach their highest point in the sky until daylight. For these radiants, it is best to view them during the last few hours before dawn. It must be remembered that meteor activity is rarely seen at its radiant position. Rather they shoot outwards from the radiant, so it is best to center your field of view so that the radiant lies toward 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 21:00 LST

Radiant Positions at 21:00 Local Summer Time

Radiant Positions at 01:00 LST

Radiant Positions at 01:00 Local Summer Time

Radiant Positions at 05:00 LST

Radiant Positions at 05:00 Local Summer Time

 

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

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The Draconids (DRA) are expected to be active on October 8/9 this year. The radiant lies at 17:20 (260) +54. This position lies in southeastern Draco, 3 degrees northwest of the 3rd magnitude star known as Rastaban (beta Draconis). These meteors are best seen hight in the northern sky just as soon as it becomes dark on the evening of October 8. With an entry velocity of 20 km/sec., the average Draconid meteor would be of slow velocity. These meteors are poorly seen from the southern hemisphere due to the low radiant altitude seen from below the equator.

We are now encountering inbound debris from comet 2P/Encke, which has its source superimposed upon the anthelion radiant. Since it has been shown that meteors from 2P/Encke are more numerous than the Anthelions, we will recognize this activity as the Southern Taurids (STA) from now until late November, when we no longer encounter remnants from comet 2P/Encke. Like the anthelion radiant, the source area is large and diffuse so observers can be liberal with the shower association of these meteors. Recent investigations of the Southern Taurids have revealed two clearly distinct components. The first component, also known as the October Arietids, represents the early and annual activity of Southern Taurids. It displays very little variation year to year. The latter component represents the main source of activity and is periodic. The early STA’s are active from September 20 through November 2 and peaks on October 14th. The main component of the STA’s are active from October 12 through November 20 and peaks on November 5th. The center of the large STA radiant is currently located at 01:59 (030) +08. This position lies in southeastern Pisces, 3 degrees southwest of the 4th magnitude star known as xi1 Ceti. This radiant is best placed near 0100 LST, when it lies on the meridian and is located highest in the southern sky. Rates at this time should be near 3 per hour no matter your location. With an entry velocity of 30 km/sec., the average STA meteor would be of medium-slow velocity.

The Orionids (ORI) are active from October 2 through November 12, with maximum activity occurring on October 21st. The radiant is currently located at 05:40  (085) +14, which places it in northern Orion, 4 degrees northeast of the 3rd magnitude star known as Meissa (lambda Orionis). This area of the sky is best placed for observing during the last dark hour prior to dawn, when it lies highest in the southern sky.  Current rates are expected to be less than 1 per hour, no matter your location. With an entry velocity of 66 km/sec., the average ORI meteor would be of swift velocity.

The delta Aurigids (DAU) are active from October 10-18 with maximum activity occurring on October 11th. On the 11th, the radiant is located at 05:36 (084) +44. This area of the sky lies in central Auriga, 4 degrees southeast of the zero magnitude star known as Capella (alpha Aurigae). To best see these meteors, face toward the northeast during the last dark hour prior to dawn. Rates at this time should be less than 1 per hour no matter your location. With an entry velocity of 64 km/sec., the average DAU meteor would be of swift velocity.

The Daytime Sextantids (DSX) are active from September 09-October 09, with maximum activity occurring on September 27th. The current position of the radiant is 10:35 (159) -04. This position lies in central Sextans, 1 degree southeast of the faint star known as delta Sextantis. Rates at this time should be less than 1 per hour no matter your location. With an entry velocity of 32 km/sec., the average DSX meteor would be of medium-slow velocity. No matter your location, these meteors are difficult to observe as the radiant lies roughly 30 degrees from the sun. Therefore, these meteors may only be seen during the last hour prior to dawn, shooting upward from the eastern horizon.

The October Camelopardalids (OCT) are expected to peak near 16:00 UT on Saturday October 5th. These meteors are only visible for 32 hours, so your location is important to see these meteors. The best location to see the 2024 peak would be Alaska as these meteors are best seen during the last few hours prior to dawn. The radiant is located at 10:56 (164) +79. This position lies in a remote area of extreme northwestern Draco. See the charts for a better idea of this location.  Hourly rates are dependent on your location, but most of us are expected to see less than 1 per hour. To best see these meteors face toward the north. With an entry velocity of 47 km/sec., the average OCT meteor would be of medium velocity.

Sporadic meteors are those meteors that cannot be associated with any known meteor shower. All meteor showers are evolving and disperse over time to the point where they are no longer recognizable. Away from the peaks of the major annual showers, these sporadic meteors make up the bulk of the activity seen each night. As seen from the mid-northern hemisphere (45N) one would expect to see during this period approximately 10 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 7 per hour as seen from rural observing sites and 2 per hour during the evening hours. Locations between these two extremes would see activity between these listed figures.

The list below offers the information in tabular form . Rates and positions are exact for Saturday night/Sunday morning.

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
Draconids (DRA) Oct 09 17:20 (260) +54 20 18:00 <1  – <1 III
Southern Taurids (STA) Oct 14 01:59 (030) +08 30 02:00 3  – 3 II
Orionids (ORI) Oct 21 05:40  (085) +14 66 06:00 <1  – <1 I
Daytime Sextantids (DSX) Sep 27 10:35 (159) -04 32 11:00 <1  – <1 IV
October Camelopardalids (OCT) Oct 05 10:56 (164) +79 47 11:00 <1  – <1 IV

Class Explanation: A scale to group meteor showers by their intensity:

  • Class I: the strongest annual showers with Zenith Hourly Rates normally ten or better.
  • Class II: reliable minor showers with ZHR’s normally two to ten.
  • Class III: showers that do not provide annual activity. These showers are rarely active yet have the potential to produce a major display on occasion.
  • Class IV: weak minor showers with ZHR’s rarely exceeding two. The study of these showers is best left to experienced observers who use plotting and angular velocity estimates to determine shower association. These weak showers are also good targets for video and photographic work. Observers with less experience are urged to limit their shower associations to showers with a rating of I to III.

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