In this contribution we review the overall features of EMIR, the NIR multiobject spectrograph of the GTC. EMIR is at present in the middle of the PD phase and will be one of the first common user instruments for the GTC, the 10 meter telescope under construction by GRANTECAN at the Roque de los Muchachos Observatory (Canary Islands, Spain). EMIR is

The Galactic Low Mass X-ray Binary GX339-4 was one of the earliest proposed black hole candidates, yet even its most fundamental binary parameters have eluded us for several decades. We present new outburst spectroscopy of GX339-4 which appears to at last reveal the motion of its elusive companion star in fluorescent NIII lines. Based on our multi

We present the dual IR camera CID for the 2.12 m telescope of the Observatorio Astronomico Nacional de Mexico, IA-UNAM. The system consists of two separate cameras/spectrographs that operate in different regions of the IR spectrum. In the near IR, CID comprises a direct imaging camera with wide band filters, a CVF, and a low resolution spectrograph

Chandra observations of M31 allow the first spatially resolved X-ray image of a supernova remnant (SNR) in an external spiral galaxy. CXOM31 J004327.7+411829 is a slightly elongated ring-shaped object with a diameter of 11'' (42 pc). In addition, the X-ray image hints that the chemical composition of the SNR is spatially dependent. The age of the

We present a model for determining the mass ratio in interacting binaries by directly fitting the observed spectrum with synthetic spectra. We make direct use of NEXTGEN model atmosphere intensities, which are the most comprehensive and detailed models available for cool stars. We fully take into account the varying temperature and gravity across

OSIRIS (Optical System for Imaging and low/intermediate-Resolution Integrated Spectroscopy) is an instrument designed to obtain images and low resolution spectra of astronomical objects in the optical domain (from 365 through 1000nm). It will be installed on Day One in the Nasmyth focus of the 10-meter Spanish GTC Telescope, although it shall be