The supernova that led a NASA scientist to remember a Spanish painter

Sometimes, watching videos from the United States special agency on astronomy ends up giving you a surprise.

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The famous physicist Albert Einstein (1879-1955) predicted the existence of gravitational lenses, which is how astronomers know the effect that a massive object, such as a galaxy, has on a beam of light. The existence of gravitational lenses was demonstrated in 1919 thanks to a solar eclipse that occurred on May 29 of that year. Basically, what a gravitational lens causes is that from Earth we observe an object in a place in the universe where it really is not, since its light beam has been curved.

On April 24, 1990, NASA launched its Hubble space telescope into orbit, a powerful tool for observing and studying the universe. Five months after its launch, NASA made a fascinating discovery: four images of a quasar reached us through a gravitational lens, called G2237+0305. The quasar appeared in four different positions, forming what NASA has named Q2237+030 or Einstein's Cross (on these lines), in the center of which is the galaxy ZW 2237+030 or Huchra Lens.

This multiple gravitational lens was seen again in November 2014. Today NASA points out that the object whose light reaches us distorted is the Redsfal supernova, named in honor of the Norwegian astrophysicist Sjur Refsdal (1935-2009), who was the one who proposed the idea of capturing multiple images to capture these lenses and study the expansion of the universe.

Einstein's Cross is visible in the galaxy cluster MACS J1149+2223, in which the blue supergiant star MACS J1149 Lensed Star 1 is located, which is the most distant star detected since Earth:is 14.4 billion light years away.

This Friday, NASA's Goddard Space Flight Center has published a video in which Doctor Brian Welch explains what this Refsdal supernova is like and how its gravitational lens works. When I was watching the video, I heard Welch make the following comment: "It almost looks like a bittle bit like a Salvador Dali painting of a galaxy", a reference to this famous Spanish painter who made me laugh. You can watch the video here:

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Main image: NASA/ESA/STScI/UCLA.