The LSST Revolution: These Data Belong To You And Me
Written by Ramisa Murshed
How will new telescope technology allow us to find out more about the galaxy we live in? Bwogger Ramisa Murshed attended the Columbia Astronomy Outreach’s latest event in their Stargazing & Lecture Series, “The LSST Revolution: These Data Belong to You and Me,” to find out.
As I entered the lecture hall in which I would soon be learning more about telescopes on the fourth floor of Pupin, I saw a multitude of faces, varying from young children to undergraduates my age to older people who looked like they had PhDs. This was the first time I had attended one of the Columbia Astronomy Outreach’s public lectures. Volunteers were giving out surveys that asked audience members for their age, profession, affiliation with Columbia, and questions that would probably be used to gain an understanding of what kinds of people were attending the events. The most striking component of these surveys, however, was the question that asked, “Did you learn something new tonight? If you answered YES, what is one thing you learned?” It was clear that the sole purpose of this Stargazing & Lecture Series was to educate, regardless of the audience members’ level of prior knowledge.
The lecture was led by Dr. Federica Bianco, a professor at NYU’s Center for Urban Science and Progress, the LSST Science Collaborations Coordinator, and the LSST Transients and Variable Stars Collaboration Chair. What exactly is LSST? Dr. Bianco began the lecture by explaining that LSST is an acronym for Large Synoptic Survey Telescope. It’s the newest survey telescope technology being developed, and it is said to be more powerful than any other survey telescopes that exist now. The survey is projected to run for ten years, from 2022 to 2032. The main idea of LSST is to take no compromises: it must be deep, wide, and fast. Dr. Bianco explains that there have been surveys in the past that have covered one or two of these aspects, but never any that have covered all three.
For LSST to be deep means that it would create a deep sky image. It would reveal all the objects in the sky, a lot of which one doesn’t typically see with the naked eye in New York City due to all the light pollution. The LSST will see more objects in the sky than other surveys as well as objects extremely far away. This, Dr. Bianco explains, will help astrophysicists learn more about the more recent universe, as the further one goes in the sky, the younger the universe is. Dr. Bianco then shows the audience brilliant Deep Field and Extreme Deep Field images taken with the Hubble Space Telescope. She then states that a single LSST image will contain 3,000 HST images, containing about 400,000 galaxies.
The next aspect of the LSST, wide, is exactly what it sounds like. The LSST is expected to create an image of half of the sky in HD, an image once again containing more astronomical matter in one image than any other survey telescope.
Finally, the LSST will be fast, meaning that it will create images and videos more quickly and frequently than current survey telescopes can. Dr. Bianco brings up the idea of the immutable sky, discussing how many people believe that the sky and galaxies don’t ever change. She follows that up by stating that the fastness of the LSST will show that the sky does, in fact, change, and pretty frequently at that: about 10 stars explode every second. With current telescope technology, we can detect only one of those explosions per night. The LSST, however, will detect thousands of stellar explosions every night. The LSST will also help astrophysicists to map explosions to stars. Dr. Bianco explained that astrophysicists want to essentially “rewind” the explosions to understand what exactly it is that exploded. The more detailed the images and videos are, the easier it is to trace the explosions back to their respective stars, which is how the LSST will aid in doing so.
Dr. Bianco called the purposes of LSST its “science drivers.” The first science driver is to study the Milky Way and its local environment, all 20 billion galaxies and 17 billion stars of it. The second science driver is to study dark energy and dark matter. There are many things humans can’t see with the naked eye because they don’t actually emit light in the electromagnetic spectrum, known as dark energy and dark matter. About 70 percent of the universe is comprised of dark energy, 25 percent dark matter, and the remaining 5 percent ordinary matter, including plants, animals, and buildings. The third science driver is to create a catalog of the solar system, including near-Earth asteroids and potential hazardous objects, main belt asteroids, and Kuiper belt objects. These objects are too small to be seen by other surveys. Not only will LSST be able to identify these objects, but it will also be able to tell what the trajectory of each object is. The final science driver that Dr. Bianco mentioned to explore the transient sky. The LSST will have a stream of one to ten million events per night, detected and transmitted within 60 seconds of observation.
The LSST will collect 20TB of data, coming in at the rate of 30GB per minute. Because the data it will produce is so massive, the LSST will have Dedicated Long Haul Networks from Chile, where the LSST is being built, to the United States. In other words, the LSST will have its own cables to transport data. The LSST is projected to take 30 seconds to produce one image, and the LSST team intends to process it in 60 seconds. All data will be available to the entire United States and Chilean scientific community and to institutes and PIs (principal investigators) who signed Memorandums of Understanding with the LSST Corporation. These data really do belong to you.
Image via Pixabay