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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

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UPCOMING METEOR SHOWERS: AUGUST 2021

Now it's the time for the encounter with one of the most popular meteor showers: the Perseids. Although this shower has proven to be very dynamic in recent years, (especially in the 1990s, due to the perihelion passage of their parent comet, 109P/Swift-Tuttle in 1992, having orbital period of about 130 years) more recently the meteor activity was mostly concentrated around the "normal" peak, with ZHR around 100 hr-1. However, the crossing of some dense streams has led to enhanced activity in several years (like 2016 for example).

Recent IMO observations found that timing of "traditional" broad maximum varied between λsol=139.8 deg to 140.3 degs, equivalent to 2021 August 12, 14h UT to August 13, 03h UT. Node is at λsol=140.0-140.1 degs so the peak is expected to occur on August 12 between 19h and 22h UT with ZHR around 110 hr-1.

No Perseids dust trail encounter are predicted for 2021; a weak filament may be crossed on August 12, 15:30 UT+- 5 hrs. The same day, there is another approach (0.0001 au) to a calculated 1-revolution trail of the comet C/1852 K1. This happens on August 12, 04h22m UT.

Of course, some minor showers will also be active in August, κ-Cygnids, daylight γ-Leonids and Aurigids being the most significant.
Last but not least, don’t forget the great help given by Sporadic Meteors: their rates are very close to annual maximum in August.

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

Southern δ-Aquariids
Active: July 12 - August 23
Maximum: July 30 (λsol= 127 degs)
ZHR: Medium (25 hr-1)

α-Capricornids
Active: July 03 - August 15
Maximum: July 30 (λsol= 127 degs)
ZHR: Low (5 hr-1)

Perseids
Active: July 17 - August 24
Maximum: August 12, 19h UT to 22h UT (node at λsol= 140.0 - 140.1 deg)
ZHR: HIGH (110 hr-1)

κ-Cignids
Active: August 03 - August 25
Maximum: August 17 (λsol= 145 deg)
ZHR: Low

γ-Leonids (Daytime shower)
Active: August 14 - September 12
Maximum: August 25 (λsol= 152.2 deg)
ZHR: Low

Source: IMO



Some tips about Perseids:

The Perseids Radiant is circumpolar (that means, is above horizon the entire day) for every observer northern of about 32 degs N latitude during shower activity.

For a Central Europe observer (say, in JN59 square and surroundings) the radiant is relatively low above horizon in late afternoon/early evening (15-18 UT) and rather high above horizon in early morning (03-06 UT). Optimal height of radiant above horizon for best radio efficiency can be found between 21 UT and 01 UT, and between 08 UT and 12 UT.

For the Central Europe observer mentioned above, the relative radiant position favors the radio paths in NE/SW direction in morning and early afternoon hours, and NW/SE direction during night hours. Best geometric efficiency direction Vs. Time around Perseids maximum can thus be summarized as follows:


N / S: 8 - 11 and 23 - 02
NE / SW: 8 - 13
E / W: 10 - 13 and 20 - 23
NW / SE: 20 - 02

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).