Gamma ray burst observations from Earth orbiting satellites and from space probes located throughout the solar system, when compared in detail, provide the presently most accurate astronomical source locations of these transients. The precision of the interplanetary network in use is maximized when three or more detectors are situated at mutually great (1 to several AU) distances. The existing network of missions equipped for this purpose consists primarily of the Ulysses solar orbiter, in a unique 5-AU orbit well out of the ecliptic plane, the GGS-Wind mission, now in cislunar space prior to service at the first Lagrangian point at about 0.01 AU, and the Compton Gamma Ray Observatory, in Earth orbit. Other Earth orbiters from the USA, Europe and Russia are also presently contributing to the network. In recent years, the Pioneer-Venus Orbiter and the Mars Observer missions each briefly completed a fully long-baseline network during the overlap of its operational period with that of the Ulysses mission. The next interplanetary mission will be the Russian Mars-96, to be launched in late 1996 with several burst sensors on board.
Kevin Hurley at UC Berkeley is the Principal Investigator of the burst experiment on Ulysses. Bonnard Teegarden at NASA Goddard is the GGS-Wind Transient Gamma Ray Spectrometer PI. Evgeny Mazets at Ioffe PTI in St. Petersburg, Russia and Thomas Cline at Goddard are the GGS-Wind Konus Co-PIs. Jerry Fishman at NASA Marshall is the Compton-GRO Burst and Transient Source Experiment PI. T. Cline, as co-investigator on Ulysses, TGRS, and BATSE, and as contributor to a recent piggyback on Mars-96, is primarily involved here at Goddard in the network.