hands-on astronomy at mauna kea
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Hands-on Astronomy at Mauna Kea
Stars and planets are too far away for us to visit (for now!), but being an astronomer is still an adventure, especially when we get to use a big telescope like this one. Come, find out what it’s like to observe Mars from the top of a mountain in Hawai’i.
On Location: Mauna KeaMauna Kea, the 13,800-foot volcano on the Big Island of Hawai’i, is one of the best sites in the world for astronomy and has 13 working telescopes near the summit.
In December 2009, our group from NASA’s Goddard Space Flight Center came to the NASA Infrared Telescope Facility (IRTF) at Mauna Kea to observe Mars with Goddard’s special instrument HIPWAC. We measured ozone in the atmosphere of Mars to help us understand the chemistry of that planet’s atmosphere.
Pleased to Meet You
Left to right:
• Ted Kostiuk, HIPWAC principal investigator
• Kelly Fast (me), Mars program principal investigator
• John Annen, HIPWAC engineer
• Timothy Livengood, Mars program co-investigator
Our team, in the lunch room at the summit.
Mauna Kea ↑
and Mars →
Looks Like
Mars
Red, powdery dirt. Dry atmosphere. Lava rock. The volcanic landscape of Mauna Kea is similar in some ways to the landscape of Mars. It seems appropriate to go to a place that looks like Mars so that we can observe Mars.
NASA/JPL/Cornell
The amount of ozone we measure tells us about the chemistry taking place in Mars’s atmosphere.
Ozone on Mars
To learn as much as we can about ozone on Mars, we move the telescope around to different locations.Solid colors: Where we took measurements with HIPWAC from the IRTF telescopeDotted tracks: Measurements by the Mars Express spacecraft
At the same time we are looking through the telescope, the European Space Agency’s Mars Express spacecraft, which orbits Mars, also observes ozone. When our measurements agree with theirs, both teams are more confident about the results, and we can combine all the measurements to study chemistry in the Martian atmosphere.
Ozone absorbs certain colors, or frequencies, of light that our eyes don’t see (infrared). HIPWAC can measure ozone absorption in the infrared. One challenge for us is that Earth’s atmosphere also contains ozone. We need to be sure that we are seeing ozone from Mars, not Earth.
HIPWAC stands for Heterodyne Instrument for Planetary Wind And Composition—a complicated name for an instrument that simply lets us study molecules such as ozone in the atmospheres of planets.
Here’s HIPWAC
Because of the motion of Mars relative to Earth, the ozone features on Mars appear at slightly different frequencies from those on Earth. This effect is called Doppler shift. A familiar example of Doppler shift is when the pitch of a siren seems to get lower as an ambulance moves away from us.
Visit to Nawahiokalani’opu’u School
We came to share
about planetary
astronomy and our
upcoming observing
run. The students had
many astronomy
questions. After our
presentations, the
sixth-grade students
gave us a tour of the
school grounds. It was
quite an honor to visit
this unique school!
Tim and I came to Hawai’i a day early to visit the Ke Kula ’o Nawahiokalani’opu’u school on the Big Island. We were greeted by students and staff with Hawai’ian chant, exchanges and song that welcomed us, related stars to life and honored Joseph Nawahiokalani’opu’u, the school’s namesake.
Nawahiokalni’opu’u is a Hawai’ian language immersion school, for grades K–12. There, Hawai’ian tradition, culture and agricultural methods are taught and practiced in addition to the academic curriculum.
Setting Up Our Instrument
We ship HIPWAC to
Hawai’i and
reassemble it on-
site. This takes a
few days because
the instrument has
mirrors, lenses, and
lasers that have to
be lined up very
carefully. Then we
test the instrument
to make sure it is
working properly. In
this photo, John and
Ted assemble the
lasers. HIPWAC is sensitive enough to distinguish ozone features on Mars and provides the only direct access to ozone on Mars from the surface of the Earth.
Remote Control
While we assemble
HIPWAC, other
astronomers use the
IRTF telescope for their
own studies. Many
astronomers are able to
make their observations
from anywhere in the
world, thanks to
videoconferencing,
internet connections and
the staff at the facility.
In this photo, telescope operator Paul Sears talks via computer to astronomer Adam Burgasser while he conducts remote observations.
Iced off the SummitEven though Mauna Kea is in Hawai’i, it’s at an elevation of almost 14,000 feet, so it is subject to weather that you might not associate with tropical islands.
One night, as we were still assembling HIPWAC, we were forced to leave the summit early because of ice. This evacuation was ordered by the telescope operator for everyone’s safety.
We walked out of the IRTF into high winds and blowing water droplets. Ice was beginning to form on the road. We drove carefully down to the dormitory, located about 5,000 feet below the summit. We stay there, rather than at the foot of the mountain, so that we have an easier time adjusting to the high-altitude conditions at the top.
Finishing Touches The threat of ice
was short-lived
and soon gave
way to a
beautiful
weather pattern
that would last
throughout the
observing run.
The work
resumed,
HIPWAC was
assembled and
its components
tested, and the
day came to
attach it to the
telescope with
the help of the
IRTF day crew. (Left) Observatory Foreman Lars Bergknut tightens the bolts that hold HIPWAC to the telescope, and (right) Electronics Technician Imai Namahoe prepares the connections between the control room and HIPWAC in the dome.
Ready and Standing By
HIPWAC is installed on the back of the orange IRTF telescope. The instrument sits in the middle of the large blue multiple instrument mount, just beyond HIPWAC’s blue electronics rack. In this photo, HIPWAC is flanked by IRTF facility instruments in stowed positions.
Our Turn on the Telescope
Tim and me in action! I hold a control paddle to move the telescope by small amounts. This way, we can point to various locations on Mars and make our measurements.
Before we looked at Mars, an IRTF operator (Bill Golisch, inset) pointed the telescope at some particular stars, such as Betelgeuse in the constellation Orion. The infrared light from the stars provided a final check of the alignment of HIPWAC’s many components. Next, we observed Mars for four nights and got some very nice data.
Pictures and text by Kelly Fast/NASA Design and editing by Elizabeth Zubritsky
We are always grateful for the support we receive from the staff at the NASA Infrared Telescope Facility, and we look forward to the next opportunity to observe from above the clouds on Mauna Kea. Aloha!
We took HIPWAC off the telescope and packed it up. Then came the long trip home. Data analysis takes some time, but we look forward to what we will learn about the chemistry of the atmosphere on Mars.
Our observing run was very successful, thanks to excellent weather and the excellent performance of HIPWAC. Over the four nights, we measured ozone at many locations on Mars and in coordination with the Mars Express spacecraft.
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