MACHO-1997-BLG-41

MACHO-1997-BLG-41, commonly abbreviated as 97-BLG-41 or MACHO-97-BLG-41, was a gravitational microlensing event located in Sagittarius which occurred in July 1999. The source star is likely a giant or subgiant star of spectral type K located at a distance of around 8 kiloparsecs (26,000 light years). The lens star is a binary system approximately 10,000 light years away in the constellation Sagittarius. The two stars are separated from each other by about 0.9 AU and have an orbital period of around 1.5 years. The most likely mass of the system is about 0.3 times that of our Sun. Star A and star B are both red dwarfs.

The first published model of the MACHO-1997-BLG-41 event using data from Mount Stromlo Observatory, Cerro Tololo Inter-American Observatory and Wise Observatory show the lens system as being located in the galactic bulge at a distance of 6.3 kiloparsecs (21,000 light years), a total system mass of about 0.8 times that of the Sun and a separation of 1.8 AU (the most likely value given a random orientation of the system). The individual components were assigned masses 0.6 and 0.16 times that of our Sun, making them an orange dwarf of spectral class K and a class M red dwarf respectively. According to this model, a planet with around 3.5 times the mass of Jupiter orbits in a circumbinary orbit around the two stars at a distance of around 7 AU (assuming random orientation of the system).

BLG-252

BLG-252 is a Brazilian cluster bomb, with the load of 248 submunitions with mixed effect antitank / mines.

Operation

After the release, in a safe distance, the bomb opens its covering shells. The opening of the shells occurs by the action of a charge, driven by mechanical time fuses, located on the warhead and tail of the artifact. The dispersion of the submunitions is obtained as a function of the rotation acquired by the bomb after the release, determining the effectiveness area.

References

BLG

BLG may refer to: