Sky-mapping telescope in Chile has local connection

The recent “first look” from the new telescope at the Vera C. Rubin Observatory in Chile has a surprising local connection. Both Steve Bellavia and Justine Haupt of the Custer Institute and Observatory in Southold participated in developing and building the retina of the Legacy Survey of Space and Time camera, or LSST, completed last year and installed at Vera C. Rubin in March of this year. 

“It was my passion, just working on this, developing and testing the sensors and designing part of the telescope for Vera C. Rubin,” said Ms. Haupt, director of the board for Custer Institute and Observatory and a researcher with the instrumentation department at Brookhaven National Laboratory. 

This LSST project, which she joined in 2008, was her first foray into her field of quantum optics and astronomy and the work shaped all that came after. 

“It wasn’t at all clear that it would get funded or it would really finish. It was my first real job, and while up publishing and inventing a few things as a result of that process, it was really exciting for me, personally. I was on it for over 10 years,” said Ms. Haupt.

The project did experience delays, which rescheduled the start date multiple times, to the point where Ms. Haupt had already moved on when news finally broke of the telescope’s success.

“I haven’t been thinking about Vera C. Rubin for the past seven years, really, at all. So, to see the first light images coming out is kind of shocking, actually. Originally, the on-sky date was, I think, 2018, and then over time, it was like, ‘Oh, we’ll probably go on-sky in 2019,’ and then it got pushed 2020 and then it just kept moving back and back and back. When this finally happened, and I saw the first pictures from it, it was like, ‘Oh, oh, we finally got there,’ ” Ms. Haupt said.

The camera at Vera C. Rubin is unique among both earth- and space-based observatories because it does not focus on one particular part of the sky. Rather, it captures an image every 15 seconds, and moves every 30 seconds, allowing it to map the full sky every three days. According to Ms. Haupt, this telescope has a very unusual optical design intended to take in an exceptionally wide field of view with an exceptionally high resolution, something that cannot be done with any other telescope.

“Most large telescopes take very long exposures, so you spend a lot of time on one part of the sky, and you get a very nice picture. Even James Webb is like that,” said Ms. Haupt. “But this takes a picture every, I think the exposure time is like 30 seconds. The whole point is that it’s imaging almost the entire sky, every three nights. So, you get the entire sky, and then you repeat it, and you repeat it. And over 10 years, you get a time lapse of the night sky.”

The Vera C. Rubin telescope is tasked only with taking the pictures; the data from them is then distributed to other observatories to be interpreted.

“So when [the LSST] discovers this supernova, what it has to do is send kind of like a telegram, email or whatever, to another observatory that can spend time looking at it, because we have to keep moving here and it can’t stop. It’s like, ‘Okay, it’s over there. Let me know, but I got to keep going,’” said Mr. Bellavia. “In other words, let’s not pick a target. Let’s pick all the targets. You know, why stay on one galaxy when you can get them all? And farm out the rest of it to smaller places so that it lets them just keep accumulating data.”

To illustrate for her interns the staggering amount of data being collected, Ms. Haupt presented images to her cohort and asked them to guess how many stars were visible.

“I don’t mean stars in the galaxy. I mean, like, how many stars are in this image? And they’re like, ‘Oh, hundreds of thousands,’ ” said Ms. Haupt. She then explained that “everything you see in a picture is a galaxy, even the faintest, most distant points of light. Those are galaxies. Those are not stars. Each of them contains hundreds of millions of stars. That’s what’s significant about this.”

The data collected at the Vera C. Rubin will be used to understand everything from the complexities of the Big Bang to the dangers presented by objects nearer to home, such as asteroids and near-Earth objects.

“In addition to looking at deep space and the origins of the universe type stuff, you can’t avoid also seeing what’s happening in our own solar system. The difference of scale is like the difference between the width of a human hair and the distance to our own sun,” Ms. Haupt said.

Ms. Haupt keeps a picture of the team who worked on the telescope to remind her of the impact her work continues to have.

“It just drives home the point that these are things that we’ve worked on directly,” she said. “We physically handle them with our own hands in some cases. Someone who was just in my office a few minutes ago, they personally touched all 189 of the [sensors] that went into the camera. You know, the actual part that is taking these pictures. That’s a very satisfying feeling.”

Mr. Bellavia also mentored engineers and scientists working on the thermal management systems of a space-based telescope that will be stationed on the far side of the moon.

“On the moon, daytime temperatures can reach 250°F (120°C), while nighttime temperatures can plummet to -208°F (-130°C),'” said Mr. Bellavia in an email. “And daytime, as well as nighttime, lasts  approximately 14 days on the moon, having a 29.5 day ‘day’, unlike Mars, which is about the same as Earth, with a 25-hour day, split roughly in half for day and night.”

According to Brookhaven National Laboratory, this instrument may be able to detect what is known as the “Dark Ages Signal.” Deep in the universe, radio waves linger from the Dark Ages, an early era that began about 380,000 years after the Big Bang, a time before stars and planets existed. Scientists have never been able to observe it due to the abundance of radio interference on Earth. Uncovering the Dark Ages Signal could reveal answers to some of the universe’s biggest mysteries, such as the nature of dark energy or the formation of the universe itself.