When the stars align just right, if the smog is swept away from the San Gabriels and the sky isn’t too bright to look toward the mountains, you can catch the silhouette of the Mount Wilson Observatory from the wide-windowed library of Pasadena City College.
That famous observatory, now hindered by light pollution, acts as a beacon calling both amateur and professional astronomers to Pasadena. Professionals are lured by world-class facilities and prestige at area institutions like CalTech, JPL, and the Carnegie Observatories. Amateur astronomers and science enthusiasts are drawn to these same institutions for their openness and public availability, which drew record numbers to JPL last week and brought curious onlookers to the Carnegie Observatory 14th annual open house Sunday afternoon, October 19, 2015.
“It’s very easy to look at the sky and wonder,” staff scientist at Carnegie Gwen Rudie said, explaining the public interest in science and space in particular.
Rudie, like many of the researchers at Carnegie, hopes to learn about the early beginnings of the universe’s formation. To do this she studies cosmic gas, the building block to forming stars and eventually whole galaxies.
“The gas we detect is just the tip of the iceberg,” Rudie said.
The gas that is detectable is observed using a “cosmic flashlight” from nearby stars and recording the shadows from the gas.
Trying to piece together the beginnings of the universe is clearly an endeavor that captivates many of the Pasadena area public, and the Carnegie observatory helps quench everyone’s scientific curiosity by providing an open space for all who care about cosmology to have their fill.
During the open house, visitors toured the machine shop where the latest instruments are made to painstaking accuracy, explored the Hale library where the discoveries of Mt. Wilson Observatory founder George Ellery Hale were on display, and posed for photos along the “Redshift Carpet.”
One particular attraction that had the 49 person capacity auditorium fully booked for the entire four-showing program was the “Lives and Deaths of Stars” Science Talk.
Post-doctoral Carnegie Fellow Jennifer Van Saders discussed the life cycle of stars and the new ways astronomers are able to research the most distant stars using sound waves. This new technique, called astroseismology, is “incredibly difficult” according to Van Saders, akin to trying to find the beam of a flashlight among the lights atop the Luxor Las Vegas hotel.
The auditorium filled with the low rumblings of the sounds of the sun made audible to the human ear as Van Saders demonstrated the way sound waves could be used to learn of the inner workings of otherwise impenetrable stars.
In the second half of the presentation, Princeton-Carnegie Fellow Benjamin Shappee talked about the death of stars and the program he created to track very bright supernovae, the All-Sky Automated Survey for Supernovae (ASAS-SN).
The ASAS-SN program utilizes two sets of four 14-cm robotic telescopes in Haleakala, HI and Cerro Tololo, Chile. The telescopes are fully automated and strategically placed on the globe to take a survey of the entire sky and provide data whenever one part of it gets noticeably brighter, possible evidence of a supernova.
“It scans the entire sky both the northern and southern hemispheres for places that got brighter or dimmer,” Shappee said in his presentation. “If there’s a problem they send me a text in the middle of the night to go fix it, which wakes my wife up and doesn’t make her very happy. But then I can fix the problem—both those problems.”
From there, Shappee can determine from the images whether the objects detected warrant further investigation from more advanced telescopes, as the ones used on ASAS-SN initial search are no more than what most of the public may have to view the night sky.
In fact, in addition to monitoring some of the images more closely with more powerful telescopes at Carnegie or in space, the observatory also releases their findings to the public and amateur astrologers sometimes are used to confirm supernova sightings and are even featured in press releases.
Because of ASAS-SN’s ability to scan both the northern and southern hemispheres, it has been responsible for two-thirds of the brightest supernovae discoveries per year, including the brightest supernovae ever found, ASAS-SN lh, which is hundreds of times more luminous than the typical supernovae and is still largely a mystery to astronomers.
Carnegie houses about a dozen post-doctoral fellows and a dozen staff members who are free to pursue whatever research they wish with long-term support, free from the need to justify their next grant, paper, or telescope time.
The scientists choose to work on projects alone or with teams from around the world, some studying the death of stars, some studying their birth, and others building the actual instruments used in the observatory.
Perhaps the most exciting new instrument in the works and modeled at the open house is the Giant Magellan Telescope at the Carnegie Observatories’ southern hemisphere site high in the Andes.
The seven-mirror, 83-foot wide state-of-the-art instrument will measure somewhere between the space shuttle and a Giant Sequoia when it becomes operational at the Las Campanas Observatory in Chile. It will be 10 times more powerful than the Hubble telescope and will allow astronomers to probe the early formation of stars and galaxies just after the big bang with “unprecedented resolution and clarity.”
Another way in which Carnegie involves the public is through its weekly colloquia. Every Tuesday a speaker considered an expert in their discipline visits the Observatory’s Golden auditorium to keep everyone up to date on their latest research.
Although the colloquium draws crowds from neighboring institutions from JPL to UCLA, most of the public will find these talks very technical. However, the observatory does produce a lecture series each spring which is more geared toward the everyday astronomer. Next spring’s lectures have yet to be announced, but to find out more about the Carnegie Observatory and to plan a visit, go to https://obs.carnegiescience.edu/