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A fireball at night, brigter than the venus - 11.8.2017 at 23.50 Vesanto Observation number 66153

Visibility III / V

Esko Lyytinen, Ursa (Helsinki)

This is a radio observation of a fireball, so I didn’t see it.

In other words, it is a scattering of a meteor-induced ionization cloud from TV image carriers in Moscow and also in St. Petersburg (and a third) that are on the same frequencies at 49.747 MHz.

I haven’t put such observations here, but now that apparently there’s also a good photographic experience of this one, I’ll put it that way.

The meteor left a reflection of the dense ionization cloud for several minutes. And both of those stations also show a head-echo, that is, those steep downward lines below the strong Moscow carrier and at the top weaker from the St. Petersburg station carrier.

These head-echoes could also be used to determine the trajectory of a meteor (especially when seen from two stations on the same) along with a picture of Pasi Lepola, perhaps roughly just one of them. It’s a moderately time-consuming task, so I’m not going to do it right away right now, but I’d be interested in not getting these photo & radio head-echo observations often and the experience would be right.

The figure shows the n 4 kHz frequency band and the time n n 23 pixels / second (on the horizontal axis). At the top, the green 50-minute time stamp on the clock stands out faintly according to the computer clock (which is usually to the right with an accuracy of a couple of seconds). Thus, over-dense reflections continue for a long time outside the image, i.e. the image is cropped in time.

The duration of the actual light flight cannot be inferred at all from the duration of the head echoes. The speed they should give when fitted in conjunction with photo observation. This was apparently Perseidi.

At least the line of the film fits it well.

More similar observations
Additional information
  • Accuracy of the given observation time?
    • Maximum of 1 minutes difference possible
  • How long time did you see the fireball fly in the sky?
    • Not known
  • Brightness of the fireball
    • A fireball at night, brighter than the Venus
Comments: 4 pcs
Janne Sievinen - 12.8.2017 at 22.26 Report this

Havaintomenetelmä on kyllä mielenkiintoinen ja nuo visuaalihavainnot samasta meteorista antanevat mahdollisuuksia erilaisiin jatkoanalyyseihin. Tästä radiohavaintomentelmästä olisi mukava kuulla vaikkapa esitelmien muodossa enemmänkin. Onkohan Suomessa paljonkin aktiivisia alan harrastajia?

Esko Lyytinen - 12.8.2017 at 23.20 Report this

Vain muutamia meitä on eli tiedän itseni mukaanlukien kolme henkilöä joskaan ei välttämättä kokoaikaa ainakaan ihan vastaavan muotoista havainnontia.


Timo Kuhmonen - 13.8.2017 at 20.51 Report this

Itse olen tehnyt joitakin kokeiluja viime aikoina aiheeseen liittyen, sekä VHF että UHF taajuuksilla. Vielä ei ole omaa jatkuvan vastaanoton asemaa toiminnassa. Tarkoitus on kuitenkin saada sellainen toimimaan (tietyt laitteistoon liittyvät asiat selvitettävänä). Pidin lyhyen esitelmän aiheesta Hauhon digikuvaajien miitissä....

Pasi Lepola - 13.8.2017 at 21.30 Report this

Erittäin mielenkiintoista dataa ja uutta tietoa! Tuntuu, että tämä raportti nostaa omankin kuvan arvoa! Iso kiitos Esko tästä!

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