2002ApJ...578L.125H

We observed the ``microquasar'' GRS 1758-258 four times with Chandra. Two observations with the imaging detector of the High Resolution Camera (HRC-I) were made in 2000 September-October spanning an intermediate-to-hard spectral transition (identified with the Rossi X-Ray Timing Explorer). Another HRC-I observation and an Advanced CCD Imaging Spectrometer/High Energy Transmission Grating (HETG) observation were made in 2001 March following a hard-to-soft transition to a very low flux state. Based on the three HRC images and the HETG zero-order image, the accurate position (J2000) of the X-ray source is R.A. = 18^h01^m12{fs}39, decl. = -25°44'36".1 (90% confidence radius = 0".45), consistent with the purported variable radio counterpart. All three HRC images are consistent with GRS 1758-258 being a point source, indicating that any bright jet is less than ∼1 lt-month in projected length, assuming a distance of 8.5 kpc.