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Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
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Introduction
Preparing for the Unexpected
Heidi Hammel is an explorer. As a planetary astronomer she is not
actually walking on the surface of other planets, but she is explor-
ing them through images. For Heidi the two giant planets Neptune
and Uranus hold a special fascination. Whether she is observing
these "ice giants" from one of the world's great observatories in
Hawaii or analyzing images that have been collected from a space
telescope, she is forever on the lookout for a discovery.
By opening her eyes to small but interesting details, Heidi is
always prepared for the unexpected. And when the unexpected
comes--even in the far reaches of the solar system--Heidi turns
it into an adventure.
Heidi and other scientists once found a giant storm on Neptune
that they expected to rage for decades. But only five years later,
Heidi discovered it had vanished. Another time Heidi led a team
of Hubble Space Telescope scientists who took photos of a battered
planet Jupiter as pieces of a fragmented comet crashed into it
every day for a week. Heidi's enthusiasm and down-to-earth
descriptions of the event made her one of the celebrities of what
became known as "the Great Comet Crash."
These discoveries have brought Heidi acclaim, but none of the
attention has changed her approach to life in the least. She still
looks to the future and sees adventure around every corner, and
she wants everyone to come along for the ride.
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Heidi turns the wheel
and starts the climb.
Far ahead is
the summit and one of
the world's great
observatories.
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1
A DATE WITH TWO
PLANETS
H eidi Hammel sits behind the wheel of her rental car,
preparing to turn off the Saddle Road, which crosses
Hawaii's Big Island between two huge volcanoes.
She grips the steering wheel a little tighter, anticipating the The IRTF (opposite)
steep, narrow, curving road that climbs the dormant Mauna Kea appears to be sitting
on top of the world.
[MOW-nah KAY-uh]. The volcano's name means "white mountain," It's one of several
so-called because its peak is often snow covered. world-class telescopes
that share the Mauna
Heidi turns the wheel and starts the climb. Far ahead is the
Kea summit. Views of
summit and one of the world's great observatories--the Infrared Uranus and Neptune
Telescope Facility (IRTF), part of the National Aeronautics and (above) are shown in
false color.
Space Administration (NASA). If all goes according to plan this
week in August 2003, she will spend three nights here observing
the giant planets Uranus and Neptune. But first she will make a stop
at the Onizuka Center for International Astronomy, located 9,300
feet above sea level. The center includes a comfortable dormitory,
which will be Heidi's home for the next four days.
The higher Heidi drives, the thinner the air becomes. At an
altitude of nearly 14,000 feet, where the Mauna Kea Observatories
are located, the air pressure is low enough to activate a passenger
airplane's emergency oxygen system. At this pressure, the body
isn't getting the oxygen it needs to function properly.
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Experienced observers like Heidi always rest for a few hours at the
center to give their bodies time to adapt before going higher.
After checking into her room, Heidi calls her husband, Tim.
JUPITER
Heidi's children in 2003 She'd love to say hello to their three children--Beatrix, Tobias,
(from left): Tobias and Lucas--but it's nearly 11 P.M. back in Connecticut. By now
(age 3), Beatrix (age 5),
they're all sound asleep. Though Heidi has been awake for 18
and Lucas (age 1).
BEYOND hours and has traveled 5,000 miles,
she wants to hear the details of
Tim's Sunday with the children.
The conversation is short because
Tim has to get up early to go to
work the next morning. But as
usual, he leaves Heidi smiling.
Then it's time to get down to
business. Heidi freshens up and
goes to the dining room for a
meal with other members of her
observing team. Her day is still
not over. As the Sun sets, she
heads up the nine-mile hill to
the IRTF--this time in a four-
wheel-drive vehicle. All but
the last mile or two is
unpaved, with switchback
curves. Until recently, it was barely wide
enough for two vehicles to pass. Near the top, the road is paved
with asphalt to avoid stirring up dust that could damage the
observatories' mirrors, lenses, and sensitive equipment. Heidi
flicks off her headlights because their glare can interfere with
observing. She peers carefully into the darkness as she approaches
the facility.
Inside, telescope operator Paul Sears is already hard at work.
Tonight Heidi won't be doing any work herself. Her main mission
is to give her body time to adjust to the thin air.
She's glad Paul is on duty. A former tour guide, he entertains
her with stories of the geology of the mountain, the history of the
Big Island, and his many nights operating the telescope. Even with
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good conversation, Heidi's long day finally catches up with her. Stars of the Milky
She heads for her vehicle and looks up at the splash of the Milky Way shine above
Mauna Kea. Against
Way overhead. Mars, glowing deep red, dominates the eastern
moonlit clouds stands
sky. Uranus and Neptune are in the same general direction but are an "ahu hoku," or
too faint to be seen by her unaided eyes. Tomorrow night the star altar, built of
rocks and topped by
IRTF Telescope will make them visible.
white coral.
Heidi drives back down the dark, winding road to the dormitory.
It's 10 P.M. when she gets there. She has been awake for 23 hours!
As she drifts off to sleep, Heidi thinks about the observations to
A DATE WITH TWO PLANETS 3
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come. Neptune is always interesting, but it's a particularly fascinating
time on Uranus, the planet with the most extreme seasons in the
solar system. Uranus is approaching an equinox--the transition
JUPITER
into spring in one hemisphere and autumn in the other. The last
time Uranus had similar weather was 42 years earlier in 1961,
BEYOND
The Strange Seasons of Uranus
Uranus takes 84 Earth years to circle the spins nearly on its side. Its north pole
Sun, so its seasons each last 21 Earth years. actually points slightly south of its
When Heidi was born, an equinox on orbital path!
Uranus was only five years away. In Earth This makes for unearthly Uranian seasons.
terms, it was like the beginning of March, The planet's north pole points nearly
the time when early signs of spring appear directly at the Sun during midsummer.
in the northern hemisphere. Forty-two years later, at the depth of
Seasonal changes on Uranus are the most northern winter, its south pole points
extreme of any planet because its axis--the at the Sun (right).
imaginary line through its north and south With such dramatic sunlight shifts,
poles--has a crazy tilt. astronomers like Heidi suspect that an
Every planet's axis is angled at least slightly equinox on Uranus must be a time of
toward the planet's orbital path around amazing seasonal change. And because
the Sun (below). Earth's tilt is fairly large. it occurs only once every 42 Earth years,
Its axis is inclined about one-quarter of the it's a once-in-a-lifetime opportunity to
way toward its orbital path. But Uranus discover something interesting.
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when the young astronomer-to-be was only a year old. No one
could have guessed that Heidi would grow up to be an expert on
Uranus and Neptune. But then no one has been able to predict
most of what has happened in the life of Heidi Hammel--not
even Heidi herself.
A DATE WITH TWO PLANETS 5
Representative terms from entire chapter:
orbital path