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Today MS
Today's Meteor Activity

The 'Today's Meteor Activity' graphic shows the averaged daily Meteor Activity provided by the Radio Meteor Observing Bulletin (RMOB). It's updated every hour. This graphic is free for linking to from your own website by using this link https://mmmonvhf.de/ms/ms.png


UPCOMING METEOR SHOWERS: DECEMBER 2021

December is, as usual, characterized by the return of one of the most active (and probably the most reliable) major annual showers: the Geminids.
Geminids maximum is expected to occur on December 14th, 07h UT, with ZHR = 150 at peak. ZHR at maximum has shown a slight increase over the last decades and reached 140-150 in all recent years. Since the peak has shown slight signs of variability in its rates and timing in recent years, please note that the more reliably-observed maxima during the past two decades have all occurred within the range λsol = 261.5 to 262.4 degs, equivalent to 2021 December 13th, 14h UT to December 14th, 12h UT. Near-peak rates usually persist for several hours, while fainter meteors should be most abundant almost a day ahead of the visual maximum. The Geminids peak is typically quite broad (thus ensuring a several-days-long period of good MS activity), although the rates sometimes decay fairly quickly after the maximum.

Regarding minor showers, Southern Emisphere observers will carefully monitor Phoenicids (peaking Dec. 2nd) and Puppids/Velids (peaking Dec. 7th). Phoenicids most impressive display was in 1956 (ZHR around 100), but significant activity was also observed on 2014 December 1st.
Have a look also to σ-Hydrids: several bright meteors have been observed and ZHR reaches 5-8. Recent IMO visual data indicate that maximum is close to λsol= 257 degs (December 9th), while video observations indicate a peak close to λsol= 254 degs (December 6th) and that σ-Hydrids might persist till December 24.

In the Northern Emisphere the most interesting among December's minor showers is Ursids. Ursids produced two major outbursts in the past 70 years (in 1945 and 1986) and several other rate enhancements as in 1988, 1994, 2000, 2006, 2007 and 2008, (the latter probably influenced by the relative proximity of the shower's parent comet, 8P/Tuttle, at perihelion in January 2008), 2011, 2014 and 2015. Around the maximum, the portion of slightly brighter shower meteors is higher than in the outer section of the shower.
The parent comet is expected to pass its perihelion on 2021 August 28. There is one dust trail passage calculated for 2021 December 22, 06h47m UT (λsol= 270.33 degs, close to the calculated 2009-2010-2013-2015 returns) with ZHR of 27 hr-1.


For Radio Observers, the (Theoretical) UT peaks for upcoming showers in December 2021 are as follows:

Phoenicids (Southern Emisphere shower)
Active: November 28 - December 09
Maximum: December 02, (λsol= 250 degs)
ZHR: Variable - typically low, but may reach 100 hr-1 or more

Puppids / Velids (Southern Emisphere shower)
Active: December 01 - December 15
Maximum: December 07 (λsol= 255 degs)
ZHR: Low (10 hr-1)

Monocerotids
Active: December 05 - December 20
Maximum: December 09 (λsol= 257 degs)
ZHR: Low

σ- Hydrids
Active: December 03 - December 20
Maximum: December 09 (λsol= 257 degs)
ZHR: Low (7 hr-1)

Geminids
Active: December 04 - December 20
Maximum: December 14, 07h UT (λsol= 262.2 degs)
ZHR: HIGH (150 hr-1)

Comae Berenicids
Active: December 12 - December 23
Maximum: December 16 (λsol= 264 degs)
ZHR: Low

December Leonis Minorids
Active: December 05 - February 04
Maximum: December 19 (λsol= 268 degs)
ZHR: Low (5 hr-1)

Ursids
Active: December 17 - December 26
Maximum: December 22 (λsol= 270.7 degs)
ZHR: Low (10 hr-1)

Source: IMO



Some tips about Geminids:

The Geminids Radiant is circumpolar (that means, is above horizon the entire day) for every observer northern of about 57 degs N latitude during shower activity. At southern latitude in Europe, the radiant will set in the late morning and rise in the early evening.

For a Central Europe observer (say, in JN59 square and surroundings) the radiant is below horizon from about 10:30 UT till about 16 UT. Radiant elevation is relatively low above horizon in late morning (08:30-10:30 UT) and late afternoon (16-18:30 UT). Radiant culminates around 01 UT and remains rather high above horizon in late night (00-03 UT). Optimal height of radiant above horizon for best radio efficiency can be found between 20 UT and 23 UT, and between 04 UT and 07 UT.

For the Central Europe observer mentioned above, the relative radiant position tends to favor especially the radio paths in N/S direction, in the morning and early night hours. Best geometric efficiency direction Vs. Time around Geminids maximum can thus be summarized as follows:

Direction of radio path vs Time for best efficiency (UT)
N / S: 04 - 06 and 20 - 22
NE / SW: 05 - 08 and 21 - 00
E / W: 01 - 02
NW / SE: 03 - 05 and 19 - 22


This calculation is valid for the center Europe observer as mentioned. Moving significantly away from that area will somewhat change the times for best efficiency, so this table should be used only for an approximate evaluation (although somehow valid for most Europe). Check your actual directions for best efficiency Vs. Time for your area, using tools like Virgo, OH5IY soft and so on. Please note that the above calculated efficiency applies better on Underdense trails ( that produce Pings), while Overdense trails ( that produce longer Bursts) are somewhat less dependent by geometry (radiant position with respect to direction of radio path).