Why is exoplanet-hunting space telescope's first photo from space blurry? ESA explains

The European Space Agency explained the specific reason why the first photo taken by the CHEOPS space telescope appears blurry

The European Space Agency (ESA) announced that its exoplanet-hunting mission has taken its first photo in space. Although the image the space telescope took looks a bit blurry, the agency noted that this will help improve the precision of the satellite's optics.

The Characterizing Exoplanet Satellite (CHEOPS) was officially launched by the ESA in December to look for alien planets outside the Solar System. The satellite aims to hunt down the exoplanets using its powerful telescope.

Photographing A Distant Star

HD 70843
Image of HD 70843, the star chosen as the first target for CHEOPS, ESA's Characterising ExOPlanet Satellite. ESA/Airbus/Mission Consortium

For its first image, CHEOPS took a photo of a distant star known as HD 70843. This stellar object is located in the constellation Cancer and is about 150 light-years from Earth's neighbourhood. The star is highlighted in CHEOPS' photo and is surrounded by other stellar objects. According to CHEOPS principal investigator Willy Benz of the University of Bern, the photo serves as a significant milestone for the mission because it means the telescope survived its trip to space.

"The first images that were about to appear on the screen were crucial for us to be able to determine if the telescope's optics had survived the rocket launch in good shape," he said in a press release. "When the first images of a field of stars appeared on the screen, it was immediately clear to everyone that we did indeed have a working telescope."

Defocusing CHEOPS' Telescope

Artist's impression of CHEOPS, ESA's CHaracterising ExOPlanet Satellite, in orbit above Earth ESA/ATG medialab

Despite the initial success of the mission, its first image appears a bit blurry. As explained by the ESA, the quality of the photo, as well as the odd shape of the star, were caused by the deliberate defocusing of the telescope. According to the agency, defocusing CHEOPS' optics can provide better precision because it spreads out the light produced by the other stars over multiple pixels.

"The peculiar shape of the stars in the image is a result of the deliberate defocusing of the CHEOPS optics, which spreads the light from each star over many pixels," the ESA explained. "This makes the measurements of the starlight more precise, as they are much less sensitive to small differences in the response of individual pixels in the CCD and to variations in the telescope pointing."

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