Analysis of large-scale ionospheric disturbances observed with ionosondes in asian part of Russia on the day of chelyabinsk meteoroid impact

We studied large-scale ionospheric disturbances observed with ionosondes in Asian part of Russia on the day of Chelyabinsk meteoroid impact (February 15, 2013). Diurnal variation in the critical frequency f oF2 from data of five ionosondes in Yekaterinburg (56.4° N, 58.6° E), Novosibirsk (54.8° N, 83.2° E), Norilsk (69.4° N, 88.1° E), Irkutsk (52.3° N, 104.3° E) and Yakutsk (62.0° N, 129.6° E)) was analyzed. The intervals of f oF2 quasi-periodic oscillations were singled out as possible ionospheric responses to the meteoroid explosion and/or passage. The most expected response was shown to be the large-scale traveling ionospheric disturbance observed at “Novosibirsk”, “Norilsk” and “Irkutsk” stations with delay rise as the distance between the station and the point of explosion increased. The disturbance was assumed to be caused by internal gravitational wave initiated by the meteoroid explosion. The possible interpretation of results is under discussion.