A star cluster is a group of stars that are sufficiently close to each other for them to be physically associated. Stars belonging to the cluster are formed together from the same cloud of interstellar gas and have approximately the same age and initial chemical composition. Because of this, and sin the stars in a […]
There is a variety of predictions from the general theory of relativity. And usually they are treated in the popular imagination somehow independently. This would be the case of gravitational waves and gravitational lenses, but in reality nothing prevent them to combine, even at a ‘micro’ level. A gravitational lens is any object that deflects […]
A group of astrophysicists (to which I have the pleasure to belong to), led by scientists from the Instituto de Astrofísica de Canarias (IAC, Spain), have recently published an article in Nature Astronomy in which the early events shaping the current view of our Galaxy, the Milky Way, have been unveiled . Such discovery has […]
Black holes are vacuum solutions of the Einstein equation. Hence, the energy-momentum tensor for a black hole is null at every point of space. The only place where its mass can be located is where there is no space, i.e., at the singularity. Hence, for a Schwarzschild black hole, the mass is located at the […]
I remember very well my physics professor during my first year at university. She stressed the importance of having clear intuitions of what physical terms mean before any mathematics was invoked. ‘Imagine someone drops an 100-gram apple 1 metre above your head’, she would say; ‘the pain you feel is the equivalent of a joule […]
Astrophysicists from Yale University have recently claimed the discovery of a galaxy lacking dark matter . But, to fully understand (and assess) the excitement produced by this paper, let’s review a couple of things regarding dark matter and galaxies. In the current lambda-Cold Dark Matter (ΛCDM) paradigm, the most accepted “theory to model the Universe […]
It is commonly said that Astronomy is an observational science. We cannot create and study stars or galaxies in our laboratories and, thus all the information we have from the Universe comes from observations. However, there is another approach: simulations. Astronomers use complex algorithms and computational techniques, in combination with the laws of physics, to […]
After all those big discoveries of the latest years (LIGO’s gravitational waves, or NASA’s TRAPPIST system, for example) I felt the need to explain how normal everyday astrophysics is dealt with. To explain the little things behind any discovery, and the scientific journey between seeing something odd in the sky and explaining it with science […]
The direct search for dark matter has been a thriving experimental field since a couple of decades, and a new and promising experimental approach has been recently developed and tested: the use of an atomic clock inner mechanics. This whole new idea seems to be relatively cheap since no huge technological development is needed, and […]
We live in a violent universe. The energy scales involved in many astrophysical processes are enough to stamp out our planet, not to talk about life as we know it. But, somehow, we have been living so far in a delicate equilibrium. Such equilibrium has been punctuated by relatively modest catastrophes that have possibly shaped […]