Talking about dark matter and concepts that make us go beyond the tangible world and the physics of the MRU is something exciting, and even more so if the news in this field is accompanied by images. It is one of the last images that the long-lived Hubble telescope still gives (in its supposed year of retirement, which perhaps does not end up being), showing us the visual effect of gravitational lenses.
The deflection of light is something that was predicted centuries ago and that Einstein “confirmed wrong”. Thanks to modern telescopes we can observe this phenomenon when a luminous object is located behind a mass accumulation (in the line of sight of the telescope), hence in this case Hubble has captured it in the Abell 2813 galaxy cluster.
Hubble, bringing the remotely far closer since 1990 (and this time with “trick”)
NASA is proud of this shot, which adds to the telescope’s vast trajectory, highlighting that we see physics in full action. It is not for less, since it is a spectacular visual test of the concept of gravitational lensing.
It is precisely what we see towards the center of the image, and not curved galaxies as it might appear. A photograph obtained by Wide Field 3 camera and Advanced Camera for Surveys of the telescope.
As we said in the introduction, for this effect to take place a large amount of mass is needed, which in this case is borne by that set of galaxies. Gravitational lenses also act with all types of electromagnetic radiation (not only visible light) and with the fact that lack chromatic aberration They are useful for getting to know distant objects better, regardless of how spectacular they may be.
Here we saw, for example, that a group of researchers managed to measure the mass of a white dwarf (Stein 2051 B) using their own distortion, thus proving Einstein’s “mistake”. In addition, the effect of gravitational lenses has also served to detect very distant objects in the universe and to obtain data on them without requiring a higher resolution than we currently have.
Of course, in addition to observing this curious effect, what Hubble confirms is that it will continue working until at some point it becomes obsolete by James Webb or its technology begins to suffer. We have already seen that it also paved the way for its successors in the search for extraterrestrial life by the techniques it allows to use, so 30 years does not seem enough for this titan of astronomy and optics.
Imagen | ESA/Hubble & NASA, D. Coe