Lunar Meteor Watch
Updated October 11, 2019
Monthly Briefings and Opportunities to Observe Lunar Meteors
For the ongoing monthly routine observations, the defined start is set at three days after New Moon until two days after First Quarter for the first half. The second half resumes two days before Last Quarter and continues until three days before New Moon. The actual duration of each observing interval will vary due to ecliptic angle, lunar elongation, and observer latitude. I am posting these plans on a quarterly basis, which provides, at a glance, the observing schedule along with any meteor showers active during the observing windows. In general the observations fall into three groups: evening, from three days after New Moon (NM) to two days after First Quarter (FQ); morning, from two days prior to Last Quarter (LQ) to three days prior to New Moon (NM); and significant shower, when the moon is favorably placed (usually during these two intervals) during annual showers (whose names will appear in bold type) with ground-based ZHR’s of 20 or more.
We have just completed the morning phase of the current campaign as of this writing (New Moon is August 30). Note that the Antihelion Source provides a weak background of meteors for 9 months of the year, with a slight increase in March-April; late May, and late June, ZHR is 4.
· Interval: 19 – 25 October (LQ = 21 October; NM = 28 October); morning-the Orionids are active along with the lesser epsilon-Geminids and Leo Minorids.
· Interval: 31 October – 6 November (NM = 28 October; FQ = 4 November), evening; minor contributions from the Northern Taurids and sporadic background.
· Interval: 17 – 23 November (LQ = 19 November; NM = 26 November), morning; the Leonids and alpha Monocerotids are active at this time.
· Interval: 29 November – 6 December (NM = 26 November; FQ = 4 December), evening; the only source of activity during this time is the Phoenicids..
· Interval: 17 – 23 December (LQ = 19 December; NM = 26 December), morning; the minor showers Ursids and December Leo Minorids are active during this interval.
· Interval: 29 December – 4 January (NM = 26 December; FQ = 2 January), evening; the Quadrantids (ZHR = 110) will peak near the end of this interval on January 4.
· Interval: 15 – 21 January (LQ = 17 January; NM = 24 January), morning; …
· Interval: 27 January – 3 February (NM = 24 January; FQ = 1 February), evening; the antihelion source and alpha Centaurids are the only sources of meteoroids active during this interval.
As always, check back often for any updates on activity related to these two major showers as well as any other developments.
The Latest Lunar Meteor Candidate Observations
I’ve received reports of some lunar Perseid candidates by Lawrence Garrett. Each of the three candidates were recorded on 5 August 2019. He observed these with a Celestron 8-inch, focal reduced to F/6.3, under clear skies with good seeing. His observing location was at Latitude 44 39.6619 degrees N, Longitude 72 59.3715 degrees West, elevation 126.5 m.
Event: 5 August 2019, 00:56:04.4021 UT, in crater South W 46.6 N 55.5, appears on 3 frames, peak is shown below
Event: 5 August 2019, 01:18:11:1010 UT C_left , Near Mons La Hire W24 N26.0, possible double impact, visible in 5 frames, peak intensity shown below
Event: 5 August 2019, 01:18:11:0676 UT C_right, Near Archimedes W1.5 N30, possible double impact, visible in 4 frames, peak intensity shown above.
I received two additional reports of possible impacts from two individual sites. The information about each is provided below. Interestingly, they took place almost exactly one month apart from each other. Confirming observations for all of these candidates are sought.
Event: 8 June 2019, 22:00:37 by ROCG ELT group in Brazil (Carlos Henrrique Barreto & Tiago Augusto Torres Moreira). Event is seen in two frames near the WNW (Selenographic coordinates “eyeballed” to approximately 72.0W, 38.5N)
Event: 8 July 2019, 1:35 UT by Roger A. Jiménez A. in Venezuela. He wrote: “[4.0] Magnitude calibrated based on the brightness of a fourth magnitude star which was 2.5 degrees from the Moon, in the direction of its illuminated side. For this estimation, the same equipment (B10x50) was used, moments after the event.” The event, lasting less than 0.1 second, was observed in the region of Pickering Crater.
Lots of Fireballs Lately…
There seems to be a lot of fireball activity lately. Check out www.imo.net to read up on the latest sightings of fireballs over various parts of the world. Most objects that create the fireballs are large enough to generate an observable impact flash on the Moon. So whether a shower is active or not, there is always the potential to witness a meteoroid impact flash on the dark (shadowed) section of the waxing or waning crescent Moon.
Super Wolf Blood Moon Total Lunar Eclipse Meteor Impact
By now many are aware of a meteoroid impact that occurred just as totality was getting underway during the recent total lunar eclipse of January 21, 2019. This occurred at 4:41:43 UT and was first seen on live streams from several locations such as Griffith Observatory. The website “HDR astrophotography by Nicolas Lefaudeux has a nice image of the impact along with a link of the best estimate of location of the resultant crater. Access this at https://hdr-astrophotography.com/the-moon/.
An eyewitness to the event as it happened, Kenneth Schroeder from Washington State, submitted this report:
“I observed this lunar meteoroid impact visually, in real time, using a pair of hand held Canon 10×42 image stabilized binoculars. I was observing from Auburn, WA, USA from a covered balcony. Partial light clouds were present during the early eclipse but skies had cleared by the time of impact at 8:41pm PST on 1/20/2019. The moon was at an approximate altitude of 38° with no obstructions.
“Visually, the flash was extremely brief, maybe 2/10 second and a pinpoint of white light. The flash was bright enough in binoculars to immediately catch my attention. There was no hesitation or waffling as to what the flash was and I thought “meteor” instantly. The Canon binoculars have a field of 6.5° so the full lunar disc was visible. My view at impact was on the center of the moon so the flash appeared almost directly down (vertical) in my field of view very close the lunar edge which was in full shadow. The impact was not in my visual blind spot which might have prevented the sighting. I continued to look for more flashes with the binoculars for about one minute but none were evident.
“During the five minutes before impact I had a Swarovski 20x-60x ATS 65mm spotting scope coupled to my Samsung Galaxy S8 phone. The phone camera was taking time-lapse images every 5 seconds. About one minute after the impact I removed the camera to scan the location with the scope at the location of the impact flash…but saw nothing unusual.
“I then up-loaded the frames from the camera to my desktop computer but, unfortunately, the time-lapse frames did not show the impact flash.
“It was on Tuesday 1/22/2019 that I saw the first online recorded videos that showed the impact flash. Using those images of the lunar disc I confirmed that the flash location matched the location that I observed in real time. What a surprise to see my visual sighting verified by a video! I have watched several of the recorded videos and still photos and believe that my visual sighting appeared to be even brighter relative to the shadowed disc than the images show. In fact, I have not ruled out the possibility that I might have seen the impact flash as a naked eye observation. I still plan to try to estimate the visual magnitude to see if a naked eye observation might have been possible.”
Dr. Schroeder has over 50 years’ experience in amateur astronomy and has better than 20/10 visual acuity. He is 100% certain of what he observed.
It was interesting to compare his observation with my own Lunar Leonid observation in November 1999. My event was bright enough for me to be absolutely certain that something happened, but I was using a 14-inch (36-cm) Cassegrain telescope, while Dr. Schroeder was using a pair of binoculars. While I was watching this eclipse visually with an 8-inch Cassegrain, and imaging it with a camera zoomed in 20x, I was not able to see or capture this event. Both of us “will always remember [our events]”!
Constantino Sigismondi brings out an interesting coincidence: Dr. Sigismondi observed an impact with a small 7×21 telescope on the eclipsed moon of 21 January 2000. This is exactly 19 years, or one whole Metonic cycle, from the recent eclipse. Dr. Sigismondi, along with Giovanni Imponente wrote about this event in 2000 in two papers in the WGN, the Journal of the International Meteor Organization. Others have reported imaging and visually observing this impact event.
Coincidentally, another event took place in the same region of the moon during the January 21, 2000 total lunar eclipse. Dr. Sigismondi observed an impact with a small 7×21 telescope on the eclipsed moon and was also observed/videotaped and confirmed by Roger Venable (IOTA/US). The interesting aspects of both meteor impact events include the similarity in date of occurrence and location on the moon. Perhaps this is indicative of an unknown meteor shower? The next Metonic eclipse of this series, in 2038, is penumbral so observations of recurrences of this nature will be impossible that day. However on or around January 21 in future years, when the moon is favorably placed for such observations. We at ALPO-LMIS will keep a special lookout for such opportunities in the future and announce when they occur so as to motivate observers to participate in this new effort.
Finally, this year’s TLE impact event has renewed interest in observing total lunar eclipses for meteor impacts. People are encouraged to check images and videos of recent total lunar eclipses for the appearance of meteoroid impacts.. Cloudy night activities that would help in this effort is if people find and watch videos via YouTube of past streaming events of lunar eclipses to look for these events. If anyone finds such event, please report these to me, the Coordinator.
Here is a list of recent and future Total Lunar Eclipses (eclipse.gsfc.nasa.gov). Visit the NASA eclipse website for more information on duration of totality and location of visibility.
2011 June 15
2011 Dec. 10
2014 Apr. 15
2014 Oct. 8
2015 Apr. 4
2015 Sep. 28
2018 Jan. 31
2018 July 27
2019 Jan. 21
2019 Jul. 16
2021 May 26
2022 May 16
2022 Nov. 8
2025 Mar. 14
2025 Sep. 7
2026 Mar. 3
Lunar Meteor Impact Flash Candidates from Geminids, December 2018
I have received reports of three lunar Geminid candidates that occurred when the shower was active in December 2018. The observations were made from ROCG in Brazil by Tiago Augusto, Torres Moreira and Carlos Henrique Barreto. These were recorded to have occurred at:
You can access a “slide show” showing each of these impacts in detail at this link. We are looking for confirming observations for these events. The team did a preliminary analysis with LunarScan and by photometric analysis and was able to rule out spurious signals. These may or may not be cosmic ray events but these represent the best impact candidates the team was able to produce.
Lunar Meteor Impact Flash Candidates from May and July 2018
The Earth narrowly missed having a global meteor storm! Would not have done any good for the observations of lunar meteors (the moon was even closer to the dense ribbon of comet debris, also…) since the Moon was New at the time. For more details, go to: https://spaceweatherarchive.com/2018/10/14/earth-dodges-a-meteor-storm/.
Last July was an active month for lunar meteor impact events. This post was made public then…
“Watch Two Meteorites Hit the Moon!”
In addition to this, I received a report a few weeks ago from Tiago Augusto in Brazil on some likely lunar meteor impacts, two of which happened about the same time. An impact flash was observed at 23:01:36 UT on July 17. This event was recorded as part of a lunar program that has been in operation for two years, made at one observatory operated by ROCG (Remote Observatory of Campos dos Goytazes) and the Exoss Lunar Team. Other observers on this team include Carlos Henrrique Barreto (who recorded what may be the same flash on 7/17/2018 at 23:01:26UT; we are as of yet unsure why this one has exactly 10 seconds difference in time from the other), and Torres Moreira.
The ROCG group in Brazil reports recording another lunar meteor impact candidate, which was recorded to occur at 21:31:14 UTC on 14 August 2018. Image of this impact is the third on the right immediately below. Confirming observations are sought after, and if you’ve recorded an impact candidate please report it as soon as possible.
Jose Madiedo reports that their team recorded two additional impact flashes on July 19 at 21:53:35UT and 22:29:07 UT, from Spain with the MIDAS system. It is likely that these four meteoroids (July 17 and 19) are associated with the alpha Capricornid meteoroid stream (although a probability of such a correlation has not been determined yet). Two flashes are shown below, each taken on July 19, at 21:53:35 UT and 22:29:07 UT, respectively. Notably the same stream (the alpha Capricornids) suspected of producing these impact flashes produced a number of fireballs in Earth’s atmosphere.
A news report about the July 17 impacts posted on the networking website LinkedIN (and also posted on space.com) stated that the meteor impacts that hit the moon on July 17 were estimated to be about the size of walnuts and determined to be members of a minor meteor stream alpha Capricornids. This minor stream is derived from the comet 169P/NEAT. Confirming observations for the above flashes are requested; also if anyone has observed a flash that needs verification, please let us know.
We have at least a fair shot at capturing lunar Perseids this month. The moon is New just before the maximum but the waning crescent Moon leading up to New, as well as, and especially the waxing crescent Moon after the 13th are favorably placed for observation of lunar Perseids. The section will continue the ongoing work of coordinating observations for this and other meteor showers throughout the remainder of 2018 and beyond. Check the ALPO website and/or join the Lunarimpacts listserve for more information.
Reports of Lunar Meteors
Lunar Geminid Watch December 2017
|The home page of ALPO currently features some observations that were made during the Geminid meteor activity last December. Visit http://alpo-astronomy.org/index.htm where it describes with an image (also shown at right, courtesy of , the observations made, collaborations performed, and impact recorded on 14 December 2017. This is a preview of the next JALPO issue due out at any time now. An organization featured in this is the NELIOTA group; more information about them, including the 30 or so impact observations made during the last two years can be viewed at their website at https://neliota.astro.noa.gr/
The image at the right was taken from a video made by Marcelo Zurita, observing from Araruna, PB, Brazil. He used a 130mm f/5 Newtonian + SCB 2000 Camera. This impact event happened at 07:13:46UT on 14 Dec. 2017 and was confirmed by Romualdo Caldas with an 8-inch Schmidt and ASI 1600 Mono Cooled Camera.
Sporadic Meteor Impact Candidate
I have received the following report from Dr. Anthony Cook, Department of Physics, Aberystwyth University, United Kingdom: “After going through some video footage I obtained back in January
for my MPhys 4th year project student, I think we may have a possible impact flash. This was recorded on 2017Jan17 UT 17:47:18 +/- a few sec. It was in the vicinity of Wolf crater. Duration about
two 1/25 sec TV frames taken on a Watec 902H. I enclose a RGB image where red is the before frame, green is the first detection, and blue is the next frame. Haven’t had a chance to de-interlace yet and pull out 1/50th sec de-interlaced fields yet.”
The image is shown below with the candidate indicated. This may have been recorded by any group in Europe, so a confirming observation is requested. It is likely a sporadic, since no major showers were active at the time of the observation.
Possible Lunar Quadrantid Meteors
During the annual Quadrantid meteor shower early in January, the Italian-Swiss group made two detections
Candidate #1: 20170101 at 17:47:15 UT, lasted 2 integration fields (40 ms), imaged with one telescope.
Candidate #2: 20170103 at 19:18:41 UT, lasted 4 integration fields (80 ms), imaged with two telescopes.
Runs were performed from Rome (Italy), Gordola and Locarno (Switzerland). The team consists of Lena Raffaello, Iten Marco, and Sposetti Stefano
The images were obtained on 1 January 2017 at 17:47:15UT and 3 January 2017 at 19:18:41
March Sporadic Meteor
Antonio Mercatali of the Unione Astrofili Italiani (UAI) group (www.uai.it) reports an observation of a suspected meteor impact flash on the lunar surface (images provided below). These appear to be a genuine meteoroid impact flash but as of this writing no known confirming observation has been submitted. The flash occurred on 12 March 2016 at 18:33:02 UT; video frame rate at 25 fps with time interval of 0.04 seconds between consecutive frames.
Possible North Taurid Meteoroid Impact
The Swiss-Italian lunar meteor monitoring group, consisting of observers Rafaello Lena, Stefano Sposetti and Marco Iten, reports the observations of several impact flashes, each of which was confirmed by Dr. J.M. Madiedo’s team. These events are summarized in the below table and were observed in Europe when the Moon was below the horizon for North America. However anyone monitoring the moon from North America with video and at least an 8-inch telescope had a good chance of observing impacts from the Northern Taurid meteor stream. The North Taurids are noted as being the very likely source of the impact that was the first of over 300 events to be observed by the Meteoroid Environment team at NASA-Marshall Space Flight Center ten years ago.
The four flash detected by Stefano have following selenographic coordinates from Dr. Lena’s preliminary computation using LTVT software package (Mosher and Bondo).
Impact flash: 7 November 2015 03:31:26 UT — longitude 50.9° E +/- 0.4 ° latitude 24.0° N +/- 0.4 °=> north edge of Mare Crisium about 104 km west of Eimmart crater (images courtesy of Stefano Sposetti)
Impact Flash: 7 November 2015 04:14:07 UT — longitude 48.8° E +/- 0.4 ° latitude 0.70° S +/- 0.3 ° => Mare Fecunditatis about 54 km north east of Messier crater
Impact Flash: 7 November 2015 05:06:45 UT — longitude 62.4° E +/- 0.4° latitude 4.90° S +/- 0.3 ° => Mare Fecunditatis about 130 km north of Langrenus crater
Impact Flash: 8 November 2015 05:14:09 UT — longitude 28.4° E +/- 0.4° latitude 7.3° S +/- 0.3 ° .=> about 83 km south of Torricelli crater
One additional flash event observed 15 November 2015 18:13:57UT has also been confirmed by J.M. Madiedo (image not presently available)
Many thanks to the Swiss-Italian team for their excellent work and for reporting these results
Information about opportunities to observe the Moon for meteor impacts in 2016 can be found on the ALPO Lunar Meteoritic Impact Search website linked in the next section.
More notes on the observations of lunar meteors
Activity in this area has been quite slow as there has not been any major meteor showers occurring when the moon is favorably placed; nor has their been any spacecraft missions to the Moon (since LADEE) needing ground-based support. Nonetheless the www.alpo-astronomy.org/lunarupload/lunimpacts.htm main website does have updated information for the campaign for the current quarter of the year (July 1 thru Sep 30).
Earlier reports and images remain archived below…
I received the following report from the Impact Observers Stefano Sposetti, Marco Iten and Raffaello Lena. They report:
Marco Iten detected an interesting luminous event most probably generated by a meteoroidal impact on the Moon occurred the 26 February 2015. The position of the flash was along the terminator. The brightness of the flash 0.16 s after the initial detection was +8.0 magV. After the main lightdrop a successive residual diffuse light lasted for several seconds. Under the assumption of a meteoroidal impact, we argue that this post luminous event and its ever-growing dimensions was likely caused by the sunlight reflection on ejected materials released by the impact. Marco Iten detected it visually using no dedicated searching software.
We placed our preliminary report here: http://digilander.libero.it/glrgroup/
or directly to the pdf file: http://www.lunar-captures.com//Selenology_Today/ST_preliminary%20report_2015.pdf
I, Brian Cudnik, showed the video of the event to Impact Expert H. Jay Melosh of Purdue University (USA) and he agrees that this appears to be a genuine impact event, with the ejection of dust that is made visible as it rises into sunlight. He suggested making measurements to find the height of the dust cloud. This animated gif image (aka, the “video”) is presented below; click on this image to view the animated gif sequence of the impact.
Lunar Project Overview (Involvement with the LADEE mission)
The LADEE (Lunar Atmosphere Dust Environment Explorer) mission is history:
We have received official word from the Mission Operations Manager – LADEE has impacted the Moon!
Last contact, before LADEE went behind the Moon, was at DOY-108 [April 18] 04:30 UTC. Re-establishment of contact would have occurred at DOY-108 05:22 UTC. After achieving over 140 days of science and meeting its primary mission goals, LADEE dropped into a lower orbit for the extended mission phase in order to collect high value science data at extremely low altitudes. In anticipation of impact, we have been downloading science data on each of today’s low-altitude passes to ensure that we retain as much of the collected data as possible.
The LADEE team is doing well, with a mixture of pride and melancholy (and some celebration!).
For the duration of the more than 140 days of LADEE operations Mr. Cudnik had been one of about two dozen coordinators worldwide who coordinated and collected lunar meteoroid flash observations (such as the examples shown below). The images will go a long way to support the efforts of the Lunar Atmosphere and Dust Environment Explorer team as they sift through much science data collected by LADEE (“LAH-Dee”) during its four-month mission. The aim is to correlated changes in dust concentration with impact events. The spacecraft made impact on the far side of the moon, out of view for ground-based observers. More information on this NASA mission can be obtained at http://www.nasa.gov/mission_pages/ladee/main/#.Uw4V1uNdV8E
The work of ground based video observers to monitor the moon with low light video cameras and telescopes in the 8 to 14 inch (20 to 36 cm) size range for up to two weeks per month will continue beyond the life of LADEE. These observations will not only support the science results of LADEE but will also continue to illuminate the frequency and size of lunar meteors, among other results. This web site will continue to serve to provide near-real-time images and information as they are received from observers. The mirror site, hosted on the Association of Lunar and Planetary Observers (ALPO) website will give dates of observations each month, background information, and other monthly updates as needed. The ALPO-based mirror site can be accessed via this URL: http://www.alpo-astronomy.org/lunarblog/lunimpacts.htm.
If you are interested in joining our efforts and want to make a scientifically useful contribution, please “tune in” to the archived workshop that was held December 5, 2013. The archive is about 4 hours in length but there is a lot of great information and discussion contained therein. View it here: http://connect.arc.nasa.gov/p4zpsnm6weh/ (you may need to copy and paste this link into your favorite browser)
Lunar Project Updates
I have not received any recent reports as of this writing aside from what I have provided below, it is possible given the weather we have been experiencing as of late, many observers may have been clouded out. Earlier observing cycles have featured impact candidates that are presented below, starting with the most recent events.
George Varros reported:
Brian, here are two candidates from Jan 5. I don’t know what to make of them. They are both single video field events and are dim but don’t look like cosmic rays because of their nice shape and brightness centroids. They have a similar look, are dim and very short, just like the one from Jan 4. (I’m rescanning everything using Lunarscan 1.5 after experiencing anomalies or unexpected results.)
Jan 5, 2014 00:12:26 Lat 15.321S Lon 25.489E inside crater Cyrillus F
Jan 5, 2014 00:31:35 Lat 15.5N Lon 20.6E
[Images courtesy of George Varros]
This is a detection by Marco Iten and Stefano Sposetti of a probable impact event on the moon. These are members of the Swiss-Italian team of lunar observers.
Date: 2014 Jan 7
UT Time: 18:19:31.0
Air mass: 1.39
Lunar coordinates: 15.5° West, 19.5° North (Mare Imbrium)
Duration: 20 ms
Presence of artificial satellites along the line-of-view: none in a 3deg diameter
Iten’s instrument: 125mm refractor with WAT902H2 Ultimate
Sposetti’s instrument: 280mm reflector with WAT902H2 Ultimate
Images courtesy of (left) M. Iten and (right) S. Sposetti.
Lunar meteor observer George Varros reports the following impact candidate:
I found a single video field event that may or may not be an impact. It occurred on Jan 4, 2014, at 23:49:37 UT, just south of Gambart B at Lat 0.979 Long -11.56 I uploaded and posted an image and a map, in a new folder labeled “01/04/2014 candidate”.
Although it’s only one video field, the event does not have the visual appearance of a cosmic ray in that it has a brighter center and is in a matrix of 3×3 pixels – it looks somewhat stellar.
It was not detected by Lunarscan probably because the event is only seen in the even video field – the odd field was blank along with the odd field of the next frame. The picture is dark because I probably have my gain set too low.
The map image in the folder was made using Registax and consists of 30 video frames surrounding the event, to help pinpoint it’s location and to boost the signal.
The image of the impact candidate is shown below (Image courtesy of George Varros):
We received several observations of likely lunar meteor impacts in December, and the images are provided below. One impact flash was observed on December 7, and another on December 8, with both observations being made by the Swiss-Italian lunar observation team. With the following images the team reports: “Saturday, Dec 7, Marco Iten, Raffello Lena, Andrea Manna and I, made some video recordings of the crescent Moon. We got good, but also poor sky conditions. 2 of us, Marco Iten and I, detected independently and simultaneously a small flash on the Moon. The image of Marco Iten [below, right] shows a very nice bright point of light, lasting about 4 fields (ie. 80 ms). My image is a lot blurred [below, left] because of wind and strong turbulence, the flash is washed out but clearly visible at the same instant and in the same lunar region. The air mass at the moment of the detection was 3.9.
No artificial satellites were along the line-of sight inside a 3deg diameter centered on the Moon coordinates. We performed no photometry of the flash. To note that Marco Iten noticed the flash visually in real time, while looking at the laptop screen.
Date: 2013 Dec 7
UT Time: 19:31:06.6
Air mass: 3.9
Lunar coordinates: 11° West, 14° South (Mare Nubium)
Duration: 80 ms
Iten’s instrument: 125mm refractor with WAT902H2 Ultimate
Sposetti’s instrument: 150mm refractor with WAT902H2 Ultimate
Analysis of the rest of the AVI-files is under way.
Best regards. For the Swiss-Italian group, Stefano Sposetti
|Courtesy S. Sposetti (left) and M. Iten (right)|
The same group reports another probable impact event on December 8, 2013:Marco Iten, Raffello Lena, Andrea Manna and I made some video recordings of the crescent Moon in the first half of December 2013. The December 8th, 2 of us, Marco Iten and Stefano Sposetti, detected independently and simultaneously a small flash on the Moon. The image of Marco Iten shows a somewhat bright point of light, lasting about 2 fields (ie. 40 ms). The flash of light in the Sposetti’s image is less evident.
The air mass at the moment of the detection was 2.19. The geostationary satellite INTELSAT 907 was at 66arcmin from the Moon centre at the moment of the detection, i.e. outside the field of view. No other satellites were in a 3degree diameter circle centered on the Moon coordinates. We performed no photometry of the flash.
Date: 2013 Dec 8
UT Time: 19:15:58.6
Air mass: 2.19
Lunar coordinates: 18° West, 50° South (Longomontanus crater border)
Duration: 40 ms
Iten’s instrument: 125mm refractor with WAT902H2 Ultimate
Sposetti’s instrument: 150mm refractor with WAT902H2 Ultimate
Best regards. For the Swiss-Italian group, Stefano Sposetti
|Courtesy S. Sposetti (left) and M. Iten (right)|