Astronomy plays a central role in advancing our understanding of the universe, but human lives are very short compared to astronomical timescales. Looking for changes in the universe demands powerful technology to catch rare events. Much of astronomy is conducted by focusing large and sensitive telescopes on narrow regions of sky. This approach is very successful when you know where to look, but transient events are constantly occurring elsewhere in areas of the sky that are not observed. Until now.
With funding from the Moore Foundation, The Ohio State University’s existing All-Sky Automated Search for Supernovae project will be expanded — doubling in size so that the entire night sky can be observed once a night, every night. Currently the All-Sky project, with initial funding from the National Science Foundation, observes the night’s sky on every clear night through two telescopes located in Chile and Hawaii. These telescopes help discover exploding stars and violent eruptions from black holes in the centers of galaxies. These transient events get reported rapidly to the astronomical community for further study. The All-Sky network has made important scientific contributions in its two years of operation. It has discovered many bright local supernovae, accounting for about 60 percent of the world’s discoveries over the two-year period. And, in the summer of 2015, the network found the most energetic supernova ever detected.
Added capacity for the project will produce the first complete and unbiased all-sky census of local supernovae, leading to an improved understanding of which stars produce each of the known types of supernova explosions. It also has the capacity to find unknown types that have eluded less capable searches. Expanding the telescopes from two sites to four not only doubles the data acquisition rate to cover the whole nighttime sky every day, it also helps reduce weather-related gaps in the data. The two new telescopes will be placed in Texas and South Africa: along with the sites in Chile and Hawaii, this system will provide a strong hedge against being clouded out and missing an important event.
In addition to doubling the size of the project, funding from the foundation will improve the system’s ability to share discoveries with the broader astronomy community. The typical path to astronomical discovery has a small number of researchers analyzing data from “their” telescope time and eventually publishing papers without others ever seeing the data. The All-Sky Survey will take a more collaborative path to discovery anchored by a public alert system and a publicly accessible database. The public alert system uses automated data analysis to rapidly identify phenomena of interest and alerts the astronomy community. Read more from The Ohio State University here.
Sharing data across the entire astronomy community is an approach the foundation has been taking in this field. Recently, the foundation provided funding to make data from Pan-STAARS – the world’s largest digital sky survey to date — publicly available. The images from the Pan-STARRS survey also serve as a reference for All-Sky Survey scientists and researchers, who now have a “before” image for almost every patch of the sky and can consult the Pan-STARRS image to see if something detected in the All-Sky Survey data is actually new or not.
Complementing the abilities of the All-Sky Survey is another foundation-funded project at Princeton dubbed HATPI — “HAT” from the Hungarian Automated Telescope constructed and operated by the principal investigator Gaspar Bakos and covering a solid angle of PI steradians on the sky at all times — about the angle covered by an umbrella held over your head.
Where the All-Sky Survey uses a smaller array of larger telescopes to make daily observations and is aimed at the discovery of events with a timescale of a few days, HATPI has a 30-second cadence through a hedgehog-like array of 63 telescopes on a single mount. HATPI will create very high precision measurements to detect the shadow of a planet crossing the (unseen) disk of nearby stars. It is also great for finding earth-threatening asteroids, all kinds of variable stars, exploding stars and possibly even the optical emission from a gravitational wave source. The telescope will be sited at Las Campanas Observatory in northern Chile. It will cover the whole sky every clear night and over the course of a year, it will record three-quarters of the entire sky. The Princeton team also aims to process the data in real time and make the results public without delay.
Our portfolio of work in astronomy is aimed at creating new opportunities for the astronomical community by enabling the development of new technologies and by making the data accessible to astronomers and enthusiasts alike. Human life is short compared to astronomical timescales, but systems of telescopes, detectors and software can reveal changes in the cosmos even when they are very rare, giving us insight into the full range of nature’s events.