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A study published in the Astrophysical Journal supports models which question the need for the existence of this form of matter in galaxies

It will be its closest approach to the Earth (its perigee), at a distance of around 107 million kilometres, which is very close, considering that it originated in the Oort Cloud, at a distance from us of about a light year (some 9.5 billion kilometres). Although on those nights it will attain maximum brightness, it has not been as bright as was expected, so that it is not easy to find it with the naked eye. So binoculars are necessary, and a sky map, and we need to be at a place with dark sky to see the central zone of the comet. In spite of that it can be found near the Great Bear, and this

El presidente del Gobierno de Canarias visita el IAC Hoy, viernes 8 de enero, el presidente del Gobierno de Canarias, Fernando Clavijo, ha visitado la sede del Instituto de Astrofísica de Canarias (IAC), en La Laguna, para reunirse personalmente con el Director del centro, Rafael Rebolo, y conocer de primera mano los proyectos en los que está involucrado el Instituto. En dicho encuentro, se le han planteado distintos asuntos que conciernen al estado actual del IAC, como el progreso de su plan estratégico y el de las grandes instalaciones telescópicas para los Observatorios de Canarias

Dark matter is a type of material which has not been observed through any telescope, but whose existence is deduced from its gravitational effects on visible matter. In 1974 the astronomer Vera Rubin measured the rotation curves of the stars in orbit around the centres of spiral galaxies and noticed that at distances greater than a certain radial distance from the nucleus the stars rotate at virtually constant velocity, independently of their distance from the  centre of rotation. However the estimates of the mass of the visible matter, the stars and the gas in the galaxy lead to predictions

The Earth’s albedo is a fundamental climate parameter for understanding the radiation budget of the atmosphere. It has been traditionally measured from space platforms, but also from the ground for sixteen years from Big Bear Solar Observatory by observing the Moon. The photometric ratio of the dark (earthshine) to the bright (moonshine) sides of the Moon is used to determine nightly anomalies in the terrestrial albedo, with the aim is of quantifying sustained monthly, annual and/or decadal changes. We find two modest decadal scale cycles in the albedo, but with no significant net change