When NASA pointed its Spitzer telescope on Oumuamua, they could not even see it.

If there is a history of space, we will remember 2018 for the many ongoing investigations of the first interstellar object ever detected by humanity. Oumuamua, the elongated piece of space stuff that could be an asteroid or comet (or maybe something else, entirely), has slipped around our Sun and has returned to space so fast that scientists have barely had time to spot it. Now, NASA says it has a better idea of ​​its size.

In the days following the detection of Oumuamua at the end of 2017, NASA has steered its Spitzer Space Telescope in the direction of the object, in the hope of learning more. on the cigar-shaped body and its orientation. He had long passed his closest approach to the Earth and had already returned to space after circling the Sun. When NASA ordered the Spitzer telescope to observe it, she saw nothing at all.

Now you can imagine that not being able to see the object at all would be a huge disappointment for the researchers, but that's not entirely true. Of course, they would have liked to see more strange visitors, but not seeing them meant that the object, at its present distance, was too small to be seen, adding yet another point of valuable data.

"" Oumuamua was full of surprises from the first day, so we were eager to see what Spitzer could show, "David Trilling, lead author of a new study published in The astronomical journal, Explain. "The fact that Oumuamua is too small to be detected by Spitzer is actually a very valuable result."

As NASA's Jet Propulsion Laboratory notes in a new blog post, the Spitzer telescope's inability to detect Oumuamua using its infrared hardware imposes a size limit on the object. As NASA explains:

This corroborates the object observations made by the Hubble Space Telescope that suggested that the object was within half a kilometer on its longest edge, but reduced the upper limit of that object. estimate of about half. Hubble's more generous observations are thought to be a byproduct of Oumuamua, much more reflective than any other comet observations of our own solar system, giving it greater impression than it really could .

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