how to be wary of images on social networks

NASA/via REUTERS The “cosmic rocks” of the Carina Nebula are seen in an image divided horizontally by a wavy line between a cloudscape that forms a nebula along the lower part and a relatively clear upper part, with data from NASA’s James Webb Space Telescope, a revolutionary instrument designed to look through the cosmos to the dawn of the universe and released on July 12, 2022. Dotted across both is a starfish field showing countless stars of many sizes. NASA, ESA, CSA, STScI, Webb ERO Production Team/Handout via REUTERS THIS PHOTO IS PROVIDED BY A THIRD PARTY. TODAY’S TPX PHOTOS


An image of the “Cosmic Rocks” taken by the James Webb Telescope and revealed on July 12, 2022

RUM – This weekend we will be rolling our eyes, both literally and figuratively. As every year, the month of August offers ideal conditions for the Night of the Stars. An event whose popularity should double in light of the excitement generated by the James Webb Space Telescope, but which also echoes another week’s news: #Chorizogate, as it is now commonly called.

Last week, noted physicist Etienne Klein posted a photo of a slice of chorizo ​​on Twitter, suggesting it was the star Proxima Centauri. An educational scam to invite internet users to beware. “ I’m sure if I hadn’t said it was a picture of James Webb it would have been much less successful “, he even confided HuffPost.

If the scientist explained and even apologized, the joke had the advantage of underlining a major phenomenon: the sharing of fake astro-photos on social networks. ” It is so extraordinary that you feel like you have access to another world and you want to believe it. However, certain details must challenge us “, warns the astrophysicist and president of the French Society for Astronomy and Astrophysics, Éric Lagadec, contacted by HuffPost.

Dunes photo for someone else

Above all, we must remember that even when we are talking about celestial bodies millions of kilometers away, there is someone on Earth who took or composed the image in question. “ There are many accounts that contain images with only ‘NASA’ in the credit. This is a first element that should raise eyebrows, NASA does not make a picture alone “, explains Éric Lagadec. For example, in one of the recent photos shared on its Instagram account, NASA states in the credit “NASA, ESA, CSA and STScI​​​​”.

As in any photographic object, we must also not forget the post-production and retouching work. This work is also done directly by scientists. The Hubble telescope did not take color images. Then prompting the scientists and their computers to combine different shots of the same object, sending data and information through the mill, ultimately yielding the impressive colors we know. This colorimetric work done by scientists makes it possible to give meaning to what would otherwise be invisible to the human eye.

Finally, beware of the captions that often accompany images presented as unpublished on social networks. If there are a lot of superlatives and few explanations, or even extremely precise numbers, again, be careful. An image widely circulated on social networks last weekend presented itself as a “space vacuum” that would have to be traversed for 732,536,988 years before encountering anything.

“Obviously it’s false, this number of years makes no sense. We can’t have that kind of precision., warns Eric Lagadec. In this case “void” it was about Barnard 68’s molecular cloud. An infrared filter shows that it is not empty at all.

Good accounts make good friends

In general, it should be remembered that an extraordinary discovery, an unprecedented scientific advance will never be made in a simple tweet, but will generate a press conference, scientific articles…” With James Webb somewhere, science is happening live. We have only started to write scientific articles, which then have to go through a peer review and verification process ” recalls Éric Lagadec.

In this sense, to sharpen your critical eye, it is better to follow Twitter and Instagram accounts that have been certified or recognized for several years for their popularization work. NASA, the European Space Agency, the Southern European Observatorythat CNESor the Instagram account dedicated to the James Webb telescope.

Many renowned astrophotographers, professional or amateur, also regularly share content on social networks.

A little closer to the stars

Above all, if the launch of the James Webb Space Telescope still promises beautiful images, it cannot do everything. ” James Webb is mainly intended to observe faint objects, in the near and mid-infrared, not for ultra-bright objects like a star ” says Eric Lagadec. It is, for example, its infrared capability that allowed JWST to obtain such a precise picture of these “cosmic rocks”. By looking through gas and dust in particular, it makes it possible to see barely formed stars.

Above all, the stars, although hundreds or even thousands of times larger than our Sun, are located at distances far too great to provide precision. The closest star that gives the clearest view of its surface is simply the Sun, recalls Éric Lagadec on Twitter.

The scientist states as an example to achieve the image below presents the star Beltegeuse, 700 light years from us and with a radius a thousand times greater than the sun, it was necessary to use the largest telescope in the world, 40 meters long, located in Chile.

Sometimes astronomers combine the power of two telescopes, which makes it possible to obtain, as you can see below, a blurred image of the surface of Antares.

To return to the photo of chorizo ​​shared by Étienne Klein, the scientist also recalls that this star in question is 50 times smaller than its cousins ​​presented above and above all that it is a red dwarf whose surface images stars are very difficult to achieve. ” The stars that you can almost get good pictures of are red giants that are dying, they are very old stars. So be careful if you are presented with an image of the surface of a red dwarf, which is a star in the process of being born “, he adds. No offense to charcuterie lovers.

Also look at The HuffPost: We’ve never seen a black hole like this

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