We present a detailed study of the gas chemical abundances in planetary nebulae (PNe), the final fate of solar-like stars, through high spatial resolution Integral Field Unit spectroscopy (IFU) obtained with the Multi Unit Spectroscopic Explorer (MUSE) attached to the 8.2-m Very Large Telescope (VLT) in Chile. We focused on three PNe with high abundance discrepancy factors (ADF > 20), which is a well-known and major unresolved problem in nebular astrophysics: chemical abundances obtained from faint optical recombination lines (ORL) yield systematically larger values than those obtained from
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Just as archaeology examines the ground with great care to find valuable objects which helps us to get to know ancient civilizations, astronomers look at the stars in the Milky Way in the hope of finding clues to help us understand the earliest period of development of our Galaxy. A team of researchers, in which the Instituto de Astrofísica de Canarias participates, publishes today in Nature the discovery of the oldest globular cluster remnant discovered to date. This study combines data from ESA's GAIA satellite with observations made at the Gran Telescopio Canarias, installed at the Roque
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In the current cosmological model, galaxies are formed in a hierarchical way, by merging with each other. These mergers can lead to kinematic anomalies that can be used to shed light onto the formation history of the galaxy. However, it is important to be able to distinguish whether these anomalies are an unambiguous signal of a past merger or if they can originate from different processes. One of these kinematic anomalies is prolate rotation. A galaxy shows prolate rotation if it rotates around its major axis. This kinematic characteristic is relatively frequent in massive galaxies and it
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Leo I is one of the youngest dwarf spheroidal (dSph) galaxies in the Local Group. Its relative isolation, extended and complex star formation history (SFH), and recent perigalacticon passage (∼1 Gyr ago) make of Leo I one of the most interesting nearby stellar systems. We derived its SFH from a deep Hubble Space Telescope colour-magnitude diagram and found that global star formation enhancements in Leo I occurred ∼13, 5.5, 2.0, and 1.0 Gyr ago, after which it was substantially quenched, most probably due to ram pressure stripping with the Milky Way halo. We interpreted the most ancient and
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An international team, including researchers from the Instituto de Astrofísica de Canarias (IAC), used combined data from different radio telescopes located in Spain to probe the mode of star formation in a galaxy when the universe had less than 30% of its current age. They revealed that the properties of the molecular gas reservoir are similar to the one of our own Galaxy, unseen up to now in the distant universe. The paper is published in the Astrophysical Journal Letters. A major question in the study of galaxies is on the mode of star formation, how efficient the conversion of cold gas
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Ultrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a bright (V-band magnitude of 10.2), nearby, and red (M-type) dwarf star every 7.7 hours. GJ 367b has a radius of 0.718 ± 0.054 Earth-radii and a mass of 0.546 ± 0.078 Earth-masses, making it a sub-Earth planet. The corresponding bulk density is 8
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