This letter presents a new solution for the Tunguska event of June 30th, 1908. The solution has been obtained starting from seismic data, is in fair agreement with the observational evidence, and supports the asteroidal hypothesis for the origin of the Tunguska cosmic body. It is based on an improved model of the hypersonic flow around a small asteroid in the Earth’s atmosphere.

This letter presents a new solution for the Tunguska event of June 30th, 1908. The solution has been obtained starting from seismic data, is in fair agreement with the observational evidence, and supports the asteroidal hypothesis for the origin of the Tunguska cosmic body. It is based on an improved model of the hypersonic flow around a small asteroid in the Earth’s atmosphere.

In this paper, we study the metric property of LexBFS-ordering on AT-free graphs. Based on a 2-sweep LexBFS algorithm, we show that every AT-free graph admits a vertex ordering, called the strong 2-cocomparability ordering, that for any three vertices u v w in the ordering, if d(u; w) 2 then d(u; v) = 1 or d(v; w) 2. As an application of this ordering, we provide a simple linear time recognitio...

A directed path graph is the intersection graph of a family of directed subpaths of a directed tree. A rooted path graph is the intersection graph of a family of directed subpaths of a rooted tree. Rooted path graphs are directed path graphs. Several characterizations are known for directed path graphs: one by forbidden induced subgraphs and one by forbidden asteroids. It is an open problem to ...