May 4 & 5 Meteors

We are now passing closest to the orbits of the Eta Aquariid (ETA) meteor stream. As a result, the number of detected ETAs has been increasing over the past 5 nights (6 on 5/1, 4 on 5/2, 9 on 5/3, 12 on 5/4 and 12 on 5/5).

My good friend Salvador Aguirre of Hermosillo, Mexico operates an all-sky camera and has been posting images and movies of the ETAs on his blog.

I was outside at 4 am this morning observing comets. Even though I wasn’t watching for meteors I did see one ETA. Comet C/2015 ER61 (PANSTARRS) is located only a few degrees from the ETA radiant. While observing the comet in 10×50 binoculars, I was able to watch an ETA brighten to visibility, move about a degree or two, leave behind a short lived trail and then flare out. This all happened within the small field-of-view of the binoculars. It was quite a sight.

The ETAs will continue to be good for the next few nights though the amount of dark time at the end of the night will be severely shortened by the Moon by early next week.

Obs Date(UT)     Time    TOT SPO ANT XLI ABO PBO ETA ELY SOP
SAL 2017-05-05  09h 11m   24  10  0   0   -   -   12  1   0
SAL 2017-05-04  09h 13m   27  13  0   1   0   0   12  0   1

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors 
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Anthelions
XLI - April Chi Librids
ABO - Alpha Bootids
PBO - Phi Bootids
ETA - Eta Aquariids
ELY - Eta Lyrids
SOP - Southern May Ophiucids
Oth - other minor showers

May 3 Meteors

The Eta Aquariids are getting more active as we approach this weekend’s peak. This morning nine ETAs were observed which is a bump up from the 4 and 6 we saw the past two nights. Though my camera is monitoring 4 other showers, all of them were quiet last night (at least in my cameras field-of-view).

The Eta Aquariids are a nice shower though only observable during the last few hours of the night. If you want to learn more about the Eta Aquariids and how to observe them, go check out Bob Lunsford’s write-up at the American Meteor Society.

Obs Date(UT)     Time    TOT SPO ANT XLI ABO PBO ETA ELY
SAL 2017-05-03  08h 40m   24  12  3   0   0   0   9   0

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors 
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Anthelions
XLI - April Chi Librids
ABO - Alpha Bootids
PBO - Phi Bootids
ETA - Eta Aquariids
ELY - Eta Lyrids
Oth - other minor showers

May 2 Meteors

Last night was another clear night over Tucson. Though the number of detected meteors dropped from one night ago, meteor rates are still healthy. The Eta Aquariids (ETA) are active during the last hours of the night. Hopefully rates will climb as we approach their peak in a few nights (May 4/5).

Obs Date(UT)     Time    TOT SPO ANT XLI ABO PBO ETA 
SAL 2017-05-02  09h 18m   19  14  1   0   0   0   4  

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors 
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Anthelions
XLI - April Chi Librids
ABO - Alpha Bootids
PBO - Phi Bootids
ETA - Eta Aquariids
Oth - other minor showers

May 1 Meteors

It has been way too long since I’ve updated this blog. Due to the constant juggle of work, family and other volunteer astronomical endeavors, updating this blog has often fallen to the bottom of the priority list. Even though this is often the case, I continue to observe comets (and coordinate the ALPO Comet Section) and run my SALSA3 meteor camera system (still part of the IMO Video Network using the MetRec meteor detection software).

The spring is usually the doldrums for meteor observing as their are few major showers and low numbers of sporadic meteors. Early May is a bit of a spring anomaly as there is a major shower active, the Comet Halley-produced Eta Aquariids (ETA). Last night my camera detected 25 meteors of which 6 were ETAs. ETA numbers should slowly increase as we approach the ETA peak on the night of May 4/5.

Obs Date(UT)     Time    TOT SPO XLI ABO PBO ETA 
SAL 2017-05-01  09h 20m   25  15  2   0   0   6  

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors 
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
XLI - April Chi Librids
ABO - Alpha Bootids
PBO - Phi Bootids
ETA - Eta Aquariids
Oth - other minor showers

Meteor Activity Outlook for May 12-18, 2012

The following is a slightly edited version of Bob Lunsford’s excellent weekly summary of meteor activity. The original version can be found at the American Meteor Society’s site.

May is a fairly slow month for meteor activity. The Eta Aquariids are very active the first two weeks of the month then fade as the month progresses. The only other showers active this month are the weak Nu Cygnids, the Eta Lyrids,  and the Antihelion radiant. These will add only 1-2 meteors per hour to the total count. Sporadic rates are low but steady as seen from the mid-northern hemisphere (45 N). Sporadic rates seen from the mid-southern hemisphere (45 S) are strong and remain so the entire month.

During this period the moon reaches its last quarter phase on Saturday the 12th. At this time the moon will be located ninety degrees west of the sun and will rise near 0100 local daylight time (LDT). As the week progresses the waning crescent moon will rise later in the morning, increasing the window of opportunity to view in totally dark conditions. The estimated total hourly rates for evening observers this week is near three for observers in the northern hemisphere and four for those south of the equator. For morning observers the estimated total hourly rates should be near nine as seen from mid-northern latitudes and fifteen from mid-southern latitudes. 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. Morning rates are reduced slightly due to moonlight during this period.

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 May 12/13. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The following showers are expected to be active this week:

The large Antihelion (ANT) radiant is currently located at 16:16 (244) -21. This position lies in northwestern Scorpius, six degrees northwest of the bright first magnitude orange star Antares (Alpha  Scorpii). Due to the large size of this radiant, Antihelion activity may also appear from western Ophiuchus, Libra, northern Lupus, as well as Scorpius. This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Rates at this time should be near one per hour as seen from the northern hemisphere and two as seen from south of the equator. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

The last of the Eta Lyrids (ELY) are visible this weekend from a radiant located at 19:23 (292) +43. This position lies in extreme eastern Lyra, four degrees southwest of the third magnitude star Delta Cygni. This shower is active from May 6 through the 14th and peaked on May 11. Rates at maximum activity are near two per hour as seen from the northern hemisphere. Unfortunately the Eta Lyrid radiant does not rise very high in the northern sky as seen from the southern hemisphere so rates seen from below the equator are minimal. Activity from this shower is best seen during the last hour before dawn when the radiant is situated highest in a dark sky. With an entry velocity of 43 km/sec., the average Eta Lyrid meteor would be of medium speed.

The Eta Aquariids (ETA) are particles from Halleys Comet, produced in Earth-crossing orbits many centuries ago. We pass closest to these orbits from May 5 through the 9th. During this period the Eta Aquariids are at their best, capable of producing ZHRs of sixty. The actual visible rates are most often less than half this figure due to the low altitude of the radiant at dawn. Observed hourly rates at maximum normally vary from zero at 60 degrees north latitude to 30 near the equator and back down to near zero again in Antarctica, where the radiant elevation is again very low. Hourly rates this weekend will most likely be less than five per hour. Rates will slowly decrease as the week progresses as we move further from the May 7 maximum. The radiant is currently located at 22:52 (343) +01. This area of the sky is located on the Aquarius/Pisces border, three degrees east of the fourth magnitude star Eta Aquarii. The best time to view this activity is during the hour before the start of morning twilight, when the radiant lies highest in a dark sky. With the moon now in the morning eastern sky, it would be best to face either due north or due south, just enough to keep the moon out of your field of view. With an entry velocity of 67 kilometers per second, a majority of these meteors will appear to move swiftly with a high percentage of the bright meteors leaving persistent trains. Surprisingly, this shower produces very few fireballs.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately four sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near two per hour. As seen from the mid-southern hemisphere (45S), morning rates would be near eight per hour as seen from rural observing sites and three per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Morning rates are reduced due to moonlight.

The table below presents a condensed version of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning.

Antihelion (ANT) – 16:16 (244) -21   Velocity 30km/sec
Northern Hemisphere – 1 per hr Southern Hemisphere – 2 per hour

Eta Lyrids (ELY) – 19:23 (292) +43   Velocity 43km/sec
Northern Hemisphere – 1 per hr Southern Hemisphere – <1 per hour

Eta Aquariids (ETA) – 22:52 (343) +01   Velocity 67km/sec
Northern Hemisphere – 3 per hr Southern Hemisphere – 5 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

 

Meteor Activity Outlook for April 28-May 4, 2012

The following is a slightly edited version of Bob Lunsford’s excellent weekly summary of meteor activity. The original version can be found at the American Meteor Society’s site.

May is a fairly slow month for meteor activity. The Eta Aquariids are very active the first two weeks of the month then fade as the month progresses. The only other showers active this month are the weak Nu Cygnids, the Eta Lyrids,  and the Antihelion radiant. These will add only 1-2 meteors per hour to the total count. Sporadic rates are low but steady as seen from the mid-northern hemisphere (45 N). Sporadic rates seen from the mid-southern hemisphere (45 S) are strong and remain so the entire month.

During this period the moon reaches its first quarter phase on Sunday the 29th. At this time the moon will be located ninety degrees east of the sun and will set near 0100 local daylight time (LDT). As the week progresses the waxing gibbous moon will set later in the morning, decreasing the window of opportunity to view in totally dark conditions. The estimated total hourly rates for evening observers this week is near three for observers in the northern hemisphere and four for those south of the equator. For morning observers the estimated total hourly rates should be near ten as seen from mid-northern latitudes and fourteen from mid-southern latitudes. 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.

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 April 28/29. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The following showers are expected to be active this week:

The last of the Pi Puppids (PPU) are seen this weekend from a radiant located at 07:32 (113) -46. This area of the sky is located central Puppis, three degrees south of the third magnitude star Sigma Puppis. This area of the sky is best seen as soon as it becomes dark during the early evening hours. Rates of less than one per hour are expected, no matter your location. Observers located in the southern hemisphere have a much better view of this activity as the radiant lies higher in the sky. At 18km/sec. the Pi Puppids would produce meteors of very slow velocity.

The large Antihelion (ANT) radiant is currently located at 15:24 (231) -19. This position lies in central Libra, directly between the third magnitude star Zubenelgenubi (Alpha Librae) and second magnitude Dschubba (Delta Scorpii). Due to the large size of this radiant, Antihelion activity may also appear from extreme eastern Hydra, eastern Virgo, northwestern Scorpius, as well as Libra. This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Rates at this time should be near two per hour as seen from the northern hemisphere and three as seen from south of the equator. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

Studies of the IMO video database by Sirko Molau and Juergen Rendtel has revealed a weak radiant active in the constellation of Cygnus this time of year. The Nu Cygnids (NCY) are active from April 18 through May 7 with maximum activity occurring on April 19. The current radiant position lies at 21:32 (323) +46. This position lies in northeast Cygnus, one degree west of the faint star Rho Cygni. The radiant is best placed during the last dark hour before dawn, when it lies highest above the horizon in a dark sky. Due to the northern declination of the radiant, this activity is not well seen from the southern hemisphere. No matter your location, rates are expected to be less than one per hour. At 42km/sec. the Nu Cygnids would produce meteors of average velocity.

The Eta Aquariids (ETA) are particles from Halleys Comet, produced in Earth-crossing orbits many centuries ago. We pass closest to these orbits from May 5 through the 9th. During this period the Eta Aquariids are at their best, capable of producing ZHRs of sixty. The actual visible rates are most often less than half this figure due to the low altitude of the radiant at dawn. Observed hourly rates at maximum normally vary from zero at 60 degrees north latitude to 30 near the equator and back down to near zero again in Antarctica, where the radiant elevation is again very low. Hourly rates this weekend will most likely be less than one per hour. Rates will slowly increase as the week progresses as we approach the May 7 maximum. The radiant is currently located at 22:14 (334) -03. This area of the sky is located in northern Aquarius, two degrees southwest of the fourth magnitude star Gamma Aquarii. The best time to view this activity is during the hour before the start of morning twilight, when the radiant lies highest in a dark sky. With the radiant low in the east it would be best to face halfway up in the sky in that same direction. If the radiant has sufficient altitude Eta Aquariid meteors can also be seen shooting down toward the eastern horizon. With an entry velocity of 67 kilometers per second, a majority of these meteors will appear to move swiftly with a high percentage of the bright meteors leaving persistent trains. Surprisingly, this shower produces very few fireballs.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately five sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near one per hour. As seen from the mid-southern hemisphere (45S), morning rates would be near ten per hour as seen from rural observing sites and two per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Evening rates are reduced due to moonlight.

The list below presents a condensed version of the expected activity this week.
Rates and positions are exact for Saturday night/Sunday morning.

Pi Puppids (PPU) – 07:32 (113) -46   Velocity 18km/sec
Northern Hemisphere – <1 per hr Southern Hemisphere – <1 per hour

Antihelion (ANT) – 15:24 (231) -19   Velocity 30km/sec
Northern Hemisphere – 2 per hr Southern Hemisphere – 3 per hour

Nu Cygnids (NCY) – 20:44 (311) +42   Velocity 42km/sec
Northern Hemisphere – <1 per hr Southern Hemisphere – <1 per hour

Eta Aquariids (ETA) – 22:14 (334) -03   Velocity 67km/sec
Northern Hemisphere – <1 per hr Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

 

May 9/10/11 Meteors

This is more like it. After 2+ months of very low meteor rates, May brings rates to be excited about. This is due to 3 factors. 1) The weather is great. May is in the middle of Tucson’s dry season. Though high cirrus is possible and you can’t rule out the rare rain event, it is usually hot and bone dry. Yesterday’s high was 101F and the humidity was a paltry 4%. 2) We have 2 active showers producing a few meteors per night, the Eta Aquarids and Eta Lyrids. 3) The number of background Sporadics are slowly increasing from their annual low in the Spring.

Obs  Date (UT)   TotTime TOT SPO ANT ETA ELY
TUS  2009-05-11  07h 42m  9   4   2   1   2
TUS  2009-05-10  08h 29m  15  8   2   4   1

TUS – Camera in Tucson operated by Carl Hergenrother
SDG – Camera in San Diego operated by Bob Lunsford
TotTime – Total amount of time each camera looked for meteors
TOT – Total number of meteors detected
SPO – Sporadics (meteors not affiliated with any particular meteor shower)
ANT – Antihelions
ETA – Eta Aquarids
ELY – Eta Lyrids