Too Many Stars!  Too Many Galaxies!  How to choose what to look

Guest: Dr Edo Berger

Near the end of Men in Black, Agent K looks up at the night sky and says:

“They’re beautiful, aren’t they? – STARS – I never look at them anymore, but … they actually are … beautiful.”

Other than seeing the stars rise, progress, and set, most of us looking at the night sky can not see the things that excite the curiosity of astronomers: like the billions of galaxies beyond our own Milky Way, the collisions of super massive black holes, and catastrophic transient events like supernovas.

Back in the 1950’s astronomers relied on earth-based observatories like Mount Palomar’s 200-inch telescope. The faint objects they could observe were truly amazing for that era.

Subsequent decades brought many new instruments to detect, observe, and record light from the stars, but they also found x-ray, radio, and infrared emissions coming from stars and black holes.  In 1990, the Hubble Space Telescope gave astronomers their first space-based observatory, enabling them to see even deeper into space, gathering and analyzing fainter, and more distant signals.  And since the signals from further away take longer to get here, observing more distant objects means seeing events much farther back in time. 

Over the next two years, if all goes as planned, three new observatories will dramatically extend the observational reach available to astronomers and astrophysicists – powers of ten deeper into space and further back in time. 

One of these is the James Webb Space Telescope. Launched in December of 2021, it is expected to be operational in 2022.  Webb will provide improved infrared resolution and sensitivity over Hubble and extend observations to objects 100 times fainter than any Hubble could detect. 

Another is the Vera C. Rubin Observatory. Located high in the Andes in Chile, it is expected to be operational near the end of 2023.  The Rubin’s wide-field reflecting telescope will scan the entire southern sky every few nights. 

The third is the LIGO gravitational wave detector array. It will allow astrophysicists to detect the collisions of black holes and neutron stars beginning in December of 2022.

Not only will these new telescopes see farther and fainter objects, they will also see many, many more objects. Previously, detection of supernovas or binary neutron stars happened in few enough numbers for astronomers to keep up with the amount of data coming in about those events.  With the Rubin, the observational data produced will be so enormous that only about a tenth of a percent can be studied in the traditional way.  How will astronomers decide which data to study?  What phenomena will they focus on?  

It’s surely an exciting time to be an astronomer.  Not only because Webb and Rubin will, we hope, become operational, but because astronomers have already begun searching for new ways to help them manage and make sense of what the new observatories will detect and record. One promising approach leverages artificial intelligence to guide them through this deluge of new data to new discoveries.

We are fortunate to have as our guest today Professor Edo Berger who is deeply involved in the Rubin Observatory’s work and who will be our guide to what interests him in deep space, and how AI will help him and his colleagues navigate this sea of data.