Measuring the masses of brown dwarfs—the lightest objects ever weighed outside the Solar System—has been a painstaking process that would have been impossible without ultra-sharp images taken with the Keck II Telescope and its world-leading adaptive optics system. These images have such high angular resolution that if a human’s eyes could act like the Keck’s adaptive optics system, he or she would be able to read a magazine from a mile away.
The positional accuracy achieved with such sharp images has enabled astronomers Michael Liu and Trent Dupuy of the Institute for Astronomy at the University of Hawai’i and Michael Ireland of the University of Sydney to determine—for the first time ever—the masses of the coldest brown dwarfs. Interestingly, their results are somewhat at odds with current theoretical predictions, challenging astronomers’ understanding of such cold objects.
It’s official—Mars has gas. Scientists recently confirmed that certain regions of the planet release methane into the Martian atmosphere. These findings open new questions about whether life exists on the Red Planet.
Earlier research suggested methane existed in the Martian atmosphere, but the results were ambiguous. Now, Michael Mumma of the NASA Goddard Spaceflight Center in Greenbelt, Md. and his colleagues have carefully observed the planet for three Martian years—the equivalent of seven Earth years. Using the W. M. Keck and the NASA Infrared telescopes atop Mauna Kea, Hawai’i, the team zeroed in on the atmosphere of the Red Planet, which ranges between 36 million to over 250 million miles from Earth depending on the planets’ orbits. The new data definitely shows that Mars is alive either biologically or geochemically.
But since astronomers can’t yet tell if the methane is a byproduct of biological or geological processes, it is almost as if the planet is “egging us on and challenging us by saying, ‘Hey, find out what this means’,” Mumma says.
Atmospheric turbulence causes stars to twinkle and blurs cosmic images making it difficult for astronomers to know if they are looking at one object or two, or even more. This turbulence trips up even the largest telescopes, including the twin Kecks.
Veteran observers Andrea Ghez of the University of California, Los Angeles and Claire Max of the University of California Santa Cruz (UCSC), however, have, respectively advanced and pioneered techniques to make the stars stop twinkling — at least from Keck’s perspective. For this and other work, Ghez has been named a MacArthur Genius, and Max has earned Princeton’s Madison Medal.
Ghez was inducted into the MacArthur Fellows Program in September 2008. The program encourages writers, scientists, artists, social scientists, humanists, teachers, entrepreneurs and others of outstanding talent to pursue their own creative, intellectual and professional goals. Ghez has spent almost a decade exploiting two techniques, speckle imaging, which digitally combines very short telescopic exposures, and adaptive optics, which corrects for atmospheric turbulence to map the movement of a group of stars.
These stars sit in the Sagittarius constellation near the center of our Milky Way galaxy. From her team’s observations, Ghez discovered that some of the stars orbit the Galactic Center at velocities that are fractions of the speed of light. The stars’ motions provide the strongest evidence for the theory that a supermassive black hole sits in the center of the Milky Way.
“The study of the black hole at the Galactic Center by Dr. Ghez is clearly one of the most impactful results that Keck Observatory has produced,” says Taft Armandroff, director of the Observatory. “To me, this work underscores the discovery potential of adaptive optics and observational programs spanning many years. Dr. Ghez’s award is well deserved.”
Winning the fellowship will allow Ghez to take more risks and pursue new ideas and areas in her research, she says. One of her ideas is to detect dark matter at the center of the Milky Way. She is also interested in studying the center of globular clusters to look for the elusive intermediate mass black hole and in studying the center of other galaxies to understand star formation in extreme environments outside our galaxy.
But, Ghez says, “right now there is still so very much to do at the center of our galaxy.” She is now focusing her research on understanding how the galaxy’s central black hole interacts with the stars, gas and dust that surround it.
Same ‘star’, different picture
Claire Max also makes ground-based telescopes see more clearly with adaptive optics. She is a co-inventor of the laser guide star adaptive optics systems used for astronomical research. For her work in this field, and her study of plasma physics, astronomy and astronomical instrumentation, Princeton University has honored Max with the 2009 James Madison Medal.
Early in her career, Max studied laser fusion at Lawrence Livermore National Laboratory, where she focused on laser-plasma interactions. Now, she directs the Center for Adaptive Optics, which is headquartered at UCSC. For her personal research, Max uses adaptive optics to study merging black holes at the centers of galaxies.
“Without Max’s leadership in implementing adaptive optics at Keck, many of our greatest contributions would not have happened. We join Princeton University in taking pride in such an impactful scientist,” Armandroff says.
Max earned her PhD from Princeton in 1972. The Association of Princeton Graduate Alumni awards the Madison Medal each year to a graduate student alumnus who has had a distinguished career, advanced the cause of graduate education or achieved an outstanding record of public service. Max is the first woman to receive the award, which is named for the fourth US president who many consider to be Princeton’s first graduate student. She received her medal and delivered an address during Princeton’s Alumni Day on Feb. 21, 2009.
W. M. Keck Observatory invited throngs of visitors to experience its world-leading astronomy enterprise during a greatly anticipated Open House on October 12, 2008. Advancement services coordinator Joan Campbell and executive assistant Leslie Kissner coordinated the event, which was held at company headquarters in Waimea. Throughout the day, Keck’s professional staff engaged guests in activites letting them explore the Observatory’s astronomy research and technological advancements.
Local resident Sharon Petrosky says she felt “connected to something bigger,” as she, along with hundreds of other visitors, gained an appreciation of the world-class Observatory located in their backyard. “I am learning so much about light, about space, about sound. Sound, for instance, is simply a vibration,” Petrosky says. “I’ve had so many compelling revelations today.”
The power of revelation was in full force at the Observatory, giving credence to this year’s theme— Welcome to the Edge of Discovery.
The stroke of midnight on Jan. 1, 2009 heralded the traditional celebrations of New Year’s Eve. It also launched the first global celebration of modern astronomy. Known as the International Year of Astronomy, or IYA 2009, the event has inspired organizations and institutions around the world to host activities commemorating the first 400 years of modern astronomy—an era that began in 1609 when Galileo first turned his telescope to the stars.
Keck Observatory kicked off its own IYA celebration during its well-attended Open House on October 12, 2008. The Observatory is also very proud to host the 2009 Maunakea Lecture Series to commemorate IYA in a year long program that shares with listeners the world class research taking place on Mauna Kea. The directors of the Mauna Kea Observatories will give the monthly lectures at the Observatory’s headquarters in Waimea and at the Imiloa Astronomy Center in Hilo throughout 2009. The talks offer a chance for the speakers to engage the public in a discussion about the research taking place at their respective facilities, inspiring audience members to embrace the Year’s central theme—The Universe, Yours to Discover.
On Jan. 15, Chad Kalepa Baybayan, the ‘Imiloa Astronomy Center’s Navigator in Residence, gave the inaugural 2009 Maunakea Lecture at Keck Observatory’s Hualalai Learning Theater. Baybayan’s talk, “Traditional Hawaiian Navigation and Sky Lore,” discussed how early Hawaiians used their powers of observation to understand the movement of the stars, as well as the conditions of the ocean and environment, to navigate the Pacific Ocean.
Worldwide more than 130 countries have planned events to let citizens appreciate astronomy and its contributions to society and culture. The United Nations Educational, Scientific and Cultural Organization and the International Astronomical Union, which initiated IYA, hosted the Year’s kick-off party on Jan. 15 and Jan. 16 in Paris. Close to 800 government representatives, diplomats, scientists, astronomy undergraduates, astronauts, industrialists and artists mingled and listened to Nobel laureates’ thoughts on astronomy and on the humbling power that observing the heavens can have for all of humanity.
For information on upcoming Hawai’i Island, national and international IYA 2009 events, click the following links to see the Mauna Kea Observatories Outreach Committee’s list, the US IYA2009 Web site and the international IYA2009 Web site.