We outline a number of science advantages for adding a K or Ks filter (lambda_c 2.15 microns) and propose to extend the wavelength coverage for WFIRST into the K-band, where the gains of going to space are much more pronounced than at shorter wavelengths.

Continuing the EURONEAR data-mining projects, we developed the VIMP tool to search for Virtual Impactor asteroids (VIs) using our Mega-Precovery archival image collection. VIMP identifies candidate images probably holding VIs which are prioritised and scrutinised by human reducers. First, we applied VIMP to the Blanco-DECam archive (about 300,000

We present time-resolved 10.4 m Gran Telescopio Canarias and 4.2 m William Herschel Telescope intermediate resolution spectroscopy of the X-ray transient MAXI J1820+070 (=ASASSN-18ey) obtained during its decline to the quiescent state. Cross-correlation of the 21 individual spectra against late-type templates reveals a sinusoidal velocity

We study a group of evolved M-stars in the Large Magellanic Cloud, characterized by a peculiar spectral energy distribution. While the 9.7 μm feature arises from silicate particles, the whole infrared data seem to suggest the presence of an additional featureless dust species. We propose that the circumstellar envelopes of these sources are

Detailed studies of nearby Local Group galaxies offer an unique window to understanding galaxy formation and evolution. The analysis of Colour-Magnitude Diagrams reaching the oldest main sequence turnoffs to determine their star formation histories ('CMD fitting') has revolutionised our understanding on how these galaxies work. In particular, the

We present the discovery of HLock01-LAB, a luminous and large Lyα nebula at z = 3.326. Medium-band imaging and long-slit spectroscopic observations with the Gran Telescopio Canarias reveal extended emission in the Lyα 1215 Å, C IV 1550 Å, and He II 1640 Å lines over ˜100 kpc, and a total luminosity LLyα = (6.4 ± 0.1)×1044 erg s-1. HLock01-LAB