Faculty of Mathematics, Physics
and Informatics
Comenius University Bratislava

Meteors

Tv meteors

 

For more than 15 years astrometric and photometric observations of asteroids and comets have been made at the Astronomical and Geophysical Observatory (AGO) of the Comenius University in Modra, as well as all-sky photographic meteor observations using photographic cameras Zeiss Distagonfitted with 3.5/30mm fish-eye lenses. Two meteor photographic cameras work one in fixed and another in a guided mode. Our station No. 21 Modra is a part of the European Network (EN) for fireball detection coordinated by Ondřejov Observatory, Czech Republic. In the past, we had used TV cameras for major meteor showers observations. Recently we have developed new fish-eye TV system to be used mainly for minor meteor shower observations (poster).

6/7. 4. 2008

 

The new fish-eye TV meteor system has started regular observations on April 1, 2007. The system consists of a fish-eye Canon 2.4/15mm objective, 2 Mullard image intensifier, Meopta 1.9/16mm lens and a Watec 120N camera. The analog video signal is digitized in real time and analysed by "UFOCapture software (author SonotaCo), which is able to detect any moving objects including meteors. The resolution of the system is 720x540 (15 arcmin/px) corresponding to a field of view of 170°x140°. The limiting stellar magnitude is +5.5m and meteors up to the magnitude +3m are detected. The system operates autonomously.

3/4. 8. 2007

 

1/2. 8. 2007

The astrometric precision of this fish-eye TV system is quite good. The standard deviation for more than 50 stars reduced by the "UFOAnalyserV2" is less than 0.05° for zenithal distances up to 60°. Also we have tested the position accuracy for several stars and planets near the horizon, where the astrometric precision of the measurement decreases up to 0.5°. The fourth order polynomial expansion used by UFOAnalyserV2 is insufficient to correct fish-eye projection, especially near horizon.

10/11. 7. 2007

Our TV system operating as a single station worked 27 nights (199 hours) during April 2007, including nights with the bright Moon. In total 300 meteors were detected. Seventy-four meteors were Lyrids based in their radiant position and angular velocity. The sporadic meteor frequency was in the range of 0.5-3 meteors per hour, depending on the Moon phase, which reduced meteor rates due to the bright background of the sky. During this month, TV and photographic fish-eye cameras observed 7 fireballs. The brightest fireball was about -10th magnitude. The orbit of the "Kozmice" fireball from April 14 was also observed by our TV system and the EN photographic cameras for which Spurný (pers. comm. 2007) calculated its precise orbit.

5/6. 7. 2007

It is already one year of regular meteor observation by video system.Until now we observed during 177 nights, which resulted to more than 10000 recorded meteors. Fo instance we observed more than 500 Geminids in the night December 14/15, 2007.

14/15. 4 2007

 

Leonids 2002

Leonids 2001

Leonids 1999

Leonids 1998

Perseids 2006