The Rubin Observatory started calling astronomers 800,000 times a night

Asteroids, exploding stars and celebrating black holes swarm in the first-ever batch of nighttime alerts from the Vera C. Rubin Observatory in Chile

By Meghan Bartels edited by Lee Billings

Wake up, astronomers: the universe is calling you.

The astronomical observatory equipped with the largest camera in the world reached a key milestone on February 24, when a complex data processing system sent hundreds of thousands of alerts to scientists eager to examine its most exciting observations.

The Vera C. Rubin Observatory began operations last year, easily capturing stunning time-lapse panoramic views of the cosmos. Rubin’s first imagesbased on just 10 hours of observations, allows space enthusiasts to zoom seemingly forever on a mostly starry sky. But vigilant astronomers were still waiting for the next step: the system that would allow automatically alert them to the most promising activity in the air sky amid the nearly 1,000 enormous images that Rubin’s telescope captures every night.

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“We can detect anything that changes and moves and appears,” said Yusra AlSayyad, an astronomer at Princeton University and Rubin’s deputy associate director for data management, at Scientific American last summer. “It’s way too much for one person to manually sift, filter and monitor themselves.”

LEARN MORE: Astronomers prepare to receive 10 million alerts per night from Rubin Observatory

So even as they were designing and building the Rubin Observatory itself, scientists were also designing an alert system to help astronomers navigate the flood of data. As soon as the telescope began its observations, the team began building a static reference image of the entire sky in impeccable detail.

Now, the data processing systems that support the observatory begin to automatically compare each new Rubin image to the corresponding section of that background model. The systems identify all differences, each one being reported individually. The algorithms can also distinguish between a potential supernova and a possible new asteroid, for example.

Alerting the scientific community is the last crucial step. Astronomers, as well as members of the public, can sign up to receive notifications based on the type of observation they are interested in and the brightness of the observation in question. And now that the alerts system is up and running, users receive a small, blurry image with astronomical metadata from each observation that matches their criteria, all just minutes after Rubin captured the original image.

On February 24, the first night of public access, the system created and distributed some 800,000 alerts, sending notifications of falling asteroids, exploding stars, bursts of supermassive black holes and other transient celestial events. This number is expected to reach millions of alerts each night.

“The scale and speed of the alerts are unprecedented,” Hsin-Fang Chiang, a software developer at the SLAC National Accelerator Laboratory, which cooperates with Rubin, said in a study. press release. “Having generated hundreds of thousands of test alerts over the past few months, we are now able to say, within minutes, with each image, ‘here’s it’ and ‘let’s go.’