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During this period, the moon reaches its first quarter phase on Thursday November 30th. At that time the moon will lie 90 degrees east of the sun and will set near 2300 local standard time (LST) on November 29th. This weekend the waxing crescent moon will set during the early evening hours and will not interfere with meteor observing during the more active morning hours. The estimated total hourly rates for evening observers this week 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 23 as seen from mid-northern latitudes (45N) and 18 as seen from tropical southern locations (25S). 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. Evening rates are reduced due to moonlight. 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 November 26/27. 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 19:00 LST

Radiant Positions at 19:00 Local Standard Time

Radiant Positions at 00:00 LST

Radiant Positions at Midnight Local Standard Time

Radiant Positions at 05:00 LST

Radiant Positions at 5:00 Local Standard Time
These sources of meteoric activity are expected to be active this week.

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The December Phoenicids (PHO) are a periodic shower that rarely produces noticeable activity. The only impressive display produced so far by this shower occurred in 1956 when ZHR’s were near 100. The normal rage for these meteors is from November 28 through December 9 with a peak on December 5. The radiant at maximum is located at 01:12 (018) -53. This position lies in southern Phoenix, 5 degrees south of the 3rd magnitude star known as beta Phoenicis. For those viewing from the northern tropics southward, this position also lies 7 degrees northwest of the bright 1st magnitude star known as Achernar (alpha Eridani). This area of the sky is best placed in the southern sky as soon as evening twilight ends. These meteors are best seen from the southern hemisphere where the radiant lies much higher in the sky. For those viewing from the northern hemisphere, only those in the northern tropics have any real chance of seeing activity from this source. At only 12 km/sec. the Phoenicids produce extremely slow meteors.

The Andromedids (AND) are the annual debris encountered from the remains of comet 3D/Biela. These meteors should not be mistaken for the great meteor storms of the 19th century as those meteors are in a slightly different orbit and irregularly encountered in early December. They are known as the December phi Cassiopeiids (DPC). The AND radiant currently is located near 01:42 (025) +41. This position lies in eastern Andromeda, just south of the 4th magnitude star known as upsilon Andromedae. This part of the sky is best placed near 2100 LST, when the radiant lies highest above the horizon. Face toward the north at this time to best see these meteors. Current rates would most likely be less than 1 per hour no matter your location. With an entry velocity of 14 km/sec., the average Andromedid meteor would be of very slow velocity.

The December phi Cassiopeiids (DPC) are the classical return of the Andromedids and the radiant that was active prior to the breakup of comet 3D/Biela in the 1840’s. This source is active from November 28 through December 10th. Maximum activity is expected to occur on December 1st when the radiant is located at 02:00 (030) +46. This area of the sky is located 3 degrees north of the 2nd magnitude double star known as Almach (gamma Andromedae A). This position is also very close to the border with Cassiopeia and in some years the radiant lies in Cassiopeia, hence the name of phi Cassiopeiids. These meteors are best seen near 2100 LST by looking toward the northern sky. Meteors from the December Phi Cassiopeiids strike the atmosphere at 17km/sec., which would produce meteors of very slow velocity. Expected rates are less than 1 per hour no matter your location.

The Southern Taurids (STA) are still active from a radiant located at 04:24 (66) +15. This position lies in central Taurus, 2 degrees southwest of the 1st magnitude orange star known as Aldebaran (alpha Tauri). To best see these meteors, one should face northward near 00:00. Rates at this time should be near 1 per hour no matter your location. With an entry velocity of 22 km/sec., the average STA meteor would be of medium-slow velocity.

The omicron Eridanids (OER) was discovered by the Japanese video meteor network SonotaCo from video data obtained during 2007-2008. These meteors are active from October 23 through December 2nd. Maximum activity is ill-defined and may occur anytime from November 3-27. The date listed in the table represents the midpoint of the activity curve and not the actual date of maximum activity. The radiant is currently located at 04:32 (68) -03, which is located in eastern Eridanus, 2 degrees northwest of the 4th magnitude star known as mu Eridani. This radiant is best placed near 0000 LST, when it lies on the meridian and is located highest in the sky. Face toward the north at this time to best see these meteors. Rates at this time should be less than 1 per hour no matter your location. With an entry velocity of 26 km/sec., the average OER meteor would be of medium-slow velocity.

The Northern Taurids (NTA) are active from a radiant located at 04:46 (71) +25. This area of the sky is located in northern Taurus, 1 degree north of the 4th magnitude star known as tau Tauri. Like the STA’s, to best see these meteors, one should face northward near 00:00 LST. Maximum activity was on November 12th so rates at this time should be near 2 per hour as seen from the Northern Hemisphere and 1 as seen from south of the equator. With an entry velocity of 25 km/sec., the average NTA meteor would be of medium-slow velocity.

The Southern chi Orionids (ORS) are usually included in the totals of the Southern Taurids, as the two radiants are separated by only 5 degrees. Careful study of this area of the sky can separate these two showers. These meteors are active from November 14 through December 16, with maximum activity occurring on December 2nd. The radiant is currently located at 04:59 (75) +18, which lies in central Taurus, 5 degrees northeast of the 1st magnitude star known as Aldebaran (alpha Tauri). This radiant is best placed in the northern sky near 0100 LST, when it lies on the meridian and is located highest in the sky. Rates at this time should be near 1 per hour no matter your location. With an entry velocity of 27 km/sec., the average ORS meteor would be of medium-slow velocity.

The November Orionids (NOO) are active from November 13 through December 12, with maximum activity occurring on November 30th. The radiant is currently located at 05:57 (089) +16. This area of the sky lies in the northeastern Orion, 9 degrees north of the 1st magnitude orange star known as Betelgeuse (alpha Orionis). This radiant is best placed in the northern sky near 0100 LST, when it lies highest above the horizon. Rates should be near 3 per hour no matter your location. With an entry velocity of 43 km/sec., most activity from this radiant would be of medium speed.

The Monocerotids (MON) become active this week from a radiant located at 06:06 (092) +10. This area of the sky is located in northern Orion, 4 degrees northeast of the 1st magnitude orange star known as Betelgeuse (alpha Orionis). This position is less than 10 degrees away from the NOO radiant so care must be taken to differentiate between these two showers. This radiant best placed near 0200 LST, when it lies highest in the northern sky. Rates should be near 1 per hour no matter your location. With an entry velocity of 44 km/sec., most activity from this radiant would be of medium speed. This shower is active from November 23rd through December 24th, with maximum activity occurring on December 11th.

It’s late November, yet the Geminids (GEM) are already active. These November Geminids were first called the theta Aurigids, but it soon became clear that they and the Geminids were one and the same. The Geminids are active from November 19th through December 24th, peaking on December 14th. The radiant currently lies at 06:27 (096) +35. This area of the sky lies in southeastern Auriga, 4 degrees northwest of the 4th magnitude star known as theta Geminorum. These meteors are best seen near 02:00 LST, when the radiant lies highest in the northern sky. Rate are expected to be less than 1 per hour, no matter your location. With an entry velocity of 32km/sec, most of these meteors would appear to possess a medium velocity.

The sigma Hydrids (HYD) are active from a radiant located at 07:44 (116) +05. This area of the sky is located in central Canis Minor, 1 degree east of the zero-magnitude star known as Procyon (alpha Canis Minoris). These meteors are active from November 24 through January 7th, with maximum activity occurring on December 7th. The activity profile is not smooth as there are several minor peaks of activity throughout the activity period. We will highlight these as they occur. To best see these meteors, face toward the north near 0300 LST. Rates should be near 1 per hour no matter your location. With an entry velocity of 60km/sec, most of these meteors would appear swift.

The alpha Monocerotids (AMO) are best known for their occasional outbursts, the last which occurred in 2019. These meteors are active from 13-27 November with maximum occurring on the 22nd. Rates away from the night of maximum are very low, far less than 1 per hour no matter your location. The radiant is currently located at 08:03 (121) +01. This area of the sky is located in eastern Canis Minor, 6 degrees southeast of the zero-magnitude star known as Procyon (alpha Canis Minoris A). To best see these meteors, face toward the north during near 0300 LST. With an entry velocity of 62km/sec, most of these meteors would appear swift.

The Puppid-Velids (PUP) are a vast complex of weak radiants located in the constellations of Puppis and Vela. Visual plots and photographic studies have revealed many radiants in this area during November and December. The combined strength of these radiants can produce a ZHR of 10. Actual hourly rates will be much less unless you happen to be observing from the deep Southern Hemisphere. Activity from this source begins around December 1st. The center of this activity is currently located at 08:10 (122) -45. This position lies in western Vela, 2 degrees northeast of the 2nd magnitude star known as gamma Velorum. Peak rates occur near December 7. These meteors are best seen near 0300 LST when the radiant lies highest above the southern horizon in a dark sky. Observers located in the Southern Hemisphere have an advantage viewing this shower as the radiant will rise higher into their sky allowing more activity to be seen. Since the radiant lies low in the south for most northern hemisphere observers, meteors seen from north of the equator tend to be long in length and long-lasting. At 40 km/sec. the Puppid-Velids produce meteors of average velocity. Note: these are also listed as the “e Velids” from several sources.

The eta Hydrids (EHY) were recently discovered by members of the Croatian Meteor Network. This radiant is active from November 26 through January 1st with maximum activity occurring on December 12th. The radiant is currently located at 08:14 (123) +04, which places it in extreme western Hydra, 7 degrees east of the zero magnitude star known as Procyon (alpha Canis Minoris). This position is close to that of the sigma Hydrids so care must be taken to separate the two sources. These meteors are best seen near 0300 LST when the radiant lies highest above the northern horizon. Current rates should be less than 1 per hour no matter your location. With an entry velocity of 62 km/sec., most activity from this radiant would be of swift speed.

The theta Pyxidids (TPY) consist of two weak showers that peak two weeks apart. The early version is active from November 27 through December 7 with maximum occurring on December 1st. The radiant is currently located at 09:01 (135) -26. This area of the sky is located in northeastern Pyxis, just west of the faint star known as kappa Pyxidis. These meteors are best seen near 0400 LST when the radiant lies nearly overhead. At 58 km/sec. the theta Pyxids would produce mostly swift meteors.

The Nov. sigma Ursae Majorids (NSU) are a weak shower active from November 17-December 2. Maximum activity occurs on November 24th. The radiant is currently located at 10:10 (152) +56. This area of the sky lies in western Ursa Major, 7 degrees west of the 2nd magnitude star known as Merak (beta Ursae Majoris). To best see these meteors, face toward the north during the last hours prior to dawn. Current rates are expected to be less than near 1 per hour, no matter your location. With an entry velocity of 56 km/sec., the average NSU meteor would be of medium-swift velocity.

The Leonids (LEO) are active from November 03-December 02 with maximum activity occurring on November 18th. The radiant is currently located at 10:41 (160) +18. This position lies in central Leo, 4 degrees southeast of the 2nd magnitude double star known as Algieba (gamma Leonis A). The Leonid radiant is best placed in the northeastern sky during the last hour before morning twilight when the radiant lies highest in a dark sky. Leonids may be seen from the Southern Hemisphere, but the viewing conditions are not quite as favorable as those north of the equator. Current rates are expected to be near 2 per hour as seen from the Northern Hemisphere and 1 as seen from south of the equator. With an entry velocity of 71 km/sec., most activity from this radiant would be of swift speed with numerous persistent trains on the brighter meteors.

The psi Ursa Majorids (PSU) were discovered by observers in Japan using data from SonotaCo. This shower is active from November 29-December 11 with maximum activity occurring on December 4th. The radiant is currently located at 10:42 (161) +48. This position lies in southern Ursa Major, 5 degrees northwest of the third magnitude star known as psi Ursae Majoris. This area of the sky is best placed during the last hour before dawn, when it lies highest above the northern horizon in a dark sky. Current rates would most likely be less than one per hour no matter your location At 60km/sec., the average psi Ursa Majorid meteor would be swift.

The December kappa Draconids (DKD) were discovered by SonotaCo during studies of new radiants in 2008-09. This shower is active from November 29 through December 13 with maximum activity occurring on December 3rd. The radiant is currently located at 11:40 (175) +74. This position lies in extreme western Draco, 12 degrees north of the 2nd magnitude star known as Dubhe (alpha Ursae Majoris). While the radiant lies above the horizon all night for most of the northern hemisphere, it is best placed during the last hour before dawn, when it lies highest above the horizon in a dark sky. Rates could reach 1 per hour on the morning of the 3rd. Away from that morning I would expect hourly rates of less than 1. Due to the high northerly declination of the radiant these meteors are not visible from most of the southern hemisphere. At 43km/sec., the average December kappa Draconid meteor would be of medium velocity.

The December rho Virginids (DRV) are active from November 29 through December 22 with peak rates occur near December 5th. The current radiant location is at 11:52 (178) +14 which places it in eastern Leo near the spot occupied by the 2nd magnitude star known as Denebola (beta Leonis). Current hourly rates would be less than 1 no matter your location. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the northern horizon in a dark sky. At 66 km/sec. the December rho Virginids would produce mostly swift meteors.

The December chi Virginids (XVI) are another shower discovered in Japan by observers using data from SonotaCo. This source is active from November 26 through December 30 with maximum occurring on December 12th. The radiant is currently located at 11:58 (180) -04, which places it in southwestern Virgo, 5 degrees southwest of the 4th magnitude star known as Zaniah (eta Virginis A). Hourly rates should be less than 1 no matter your location. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the northern horizon in a dark sky. At 68 km/sec. the December chi Virginids would produce mostly swift meteors.

The December sigma Virginids (DSV) is a source of long duration discovered by John Greaves using the data of SonotaCo. This source is active from November 26 through January 24 with peak rates occur near December 21st. The current radiant location is at 12:26 (186) +10 which places it in northwestern Virgo, 6 degrees west of the 3rd magnitude star known as Vindemiatrix (epsilon Virginis). Current hourly rates would be less than 1 no matter your location. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the northern horizon in a dark sky. At 69 km/sec. the December Sigma Virginids would produce mostly swift meteors.

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 12 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 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 these listed figures. Evening rates are reduced during this period due to moonlight.

You can keep track of the activity of these meteor showers as well as those beyond the limits of visual observing by visiting the NASA Meteor Shower Portal available at: https://meteorshowers.seti.org/ You can move the sky globe to see different areas of the sky. Colored 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 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 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.

 
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
December Phoenicids (PHO) Dec 05 01:12 (018) -53 12 20:00 <1 – <1 III
Andromedids (AND) Nov 06 01:42 (025) +41 14 21:00 <1 – <1 IV
December phi Cassiopeiids (DPC) Dec 01 02:00 (030) +46 17 21:00 <1 – <1 III
Southern Taurids (STA) Nov 05 04:24 (066) +15 22 00:00 1 – 1 II
omicron Eridanids (OER) Nov 13 04:13 (063) -02 27 00:00 <1 – <1 IV
Northern Taurids (NTA) Nov 12 04:20 (065) +24 26 00:00 2 – 2 II
Southern chi Orionids (ORS) Dec 02 04:59 (075) +18 27 00:00  1 – 1 IV
Nov. Orionids (NOO) Nov 30 05:57 (089) +16 43 01:00 3 – 3 II
Monocerotids (MON) Dec 11 06:06 (092) +10 44 02:00 1 – 1 II
Geminids (GEM) Dec 14 06:27 (096) +35 32 02:00 <1 – <1 I
sigma Hydrids (HYD) Dec 07 07:44 (116) +05 60 03:00 1 – 1 II
alpha Monocerotids (AMO) Nov 22 08:03 (121) +01 62 03:00 <1 – <1 III
Puppid-Velids (PUP) Dec 07 08:10 (122) -45 40 03:00 <1 – <1 II
eta Hydrids (EHY) Dec 12 08:14 (123) +04 62 03:00 <1 – <1 IV
theta Pyxidids (TPY) Dec 01 09:01 (135) -26 58 0400 <1 – <1 IV
Nov. sigma Ursae Majorids (NSU) Nov 24 10:10 (152) +56 56 05:00 <1 – <1 IV
Leonids (LEO) Nov 18 10:41 (160) +18 71 06:00 2 – 1 I
psi Ursa Majorids (PSU) Dec 04 10:42 (161) +48 60 06:00 <1 – <1 II
December kappa Draconids (DKD) Dec 03 11:40 (175) +74 43 07:00 <1 – <1 IV
December rho Virginids (DRV) Dec 05 11:52 (178) +14 66 07:00 <1 – <1 IV
December chi Virginids (XVI) Dec 12 11:58 (180) -04 68 07:00 <1 – <1 IV
December sigma Virginids (DSV) Dec 21 12:26 (186) +10 69 08:00 <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.

Zgodnie z:
Robert Lunsford


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