[dramatic percussion music]
>> HEY, WELCOME TO "NASA LAUNCHPAD."
I'M YOUR HOST, JUSTIN TULLY.
OKAY, SO I KNOW HOW MUCH THE STARS FASCINATE YOU
AND THE THOUGHT OF LOOKING THROUGH A SPECIAL TELESCOPE
TO SEE THINGS NOBODY ELSE HAS EVER SEEN.
WELL, EVER THOUGHT ABOUT VISITING THE OBSERVATORIES
ON MAUNA KEA IN BEAUTIFUL HAWAII?
FIRST STOP WOULD BE THE VISITOR INFORMATION STATION.
HERE YOU CAN LEARN ABOUT THE MOUNTAIN,
THE TELESCOPES, AND THE UNIVERSE
AND VIEW THE STARS AFTER DARK
USING PORTABLE TELESCOPES AT THIS SITE.
OF COURSE, YOU CAN'T ACTUALLY
LOOK THROUGH THE TELESCOPES AT THE OBSERVATORIES.
IN FACT, NO VISITORS ARE EVEN ALLOWED
UP TO THE SUMMIT AFTER DARK.
TO GET TO THE OBSERVATORIES THEMSELVES,
YOU HAVE ANOTHER LONG DRIVE TO THE TOP OF THE SUMMIT.
THE HIGH ALTITUDE OF THE OBSERVATORY
CAN CAUSE SERIOUS HEALTH RISKS, INCLUDING SEVERE HEADACHES,
BREATHING DIFFICULTIES, COUGHING,
BLUE LIPS OR FINGERNAILS,
AND MAY IMPAIR PHYSICAL AND MENTAL ACTIVITY.
AND THE ROAD CAN BE DANGEROUS, ESPECIALLY IN SNOW.
SNOW. WAIT A MINUTE.
I THOUGHT WE WERE GOING TO HAWAII,
YOU KNOW: SAND, SURF, BEAUTIFUL BEACHES, AND SUNTANS.
WHO SAID ANYTHING ABOUT SNOW?
BUT TO SEE THE HAWAIIAN OBSERVATORIES,
YOU MUST GO UP...
UP, UP, TO THE TOP OF MAUNA KEA,
THE TALLEST MOUNTAIN IN THE WORLD.
YEAH, I KNOW;
MOUNT EVEREST IS THE HIGHEST MOUNTAIN IN THE WORLD,
STANDING AT NEARLY 8,850 METERS ABOVE SEA LEVEL.
BUT MAUNA KEA IS THE TALLEST MOUNTAIN,
RISING ABOUT 10,200 METERS FROM THE PACIFIC OCEAN FLOOR.
ONLY ABOUT 4,200 METERS,
OR NEARLY 14,000 FEET, OF MAUNA KEA MOUNTAIN
SIT ABOVE SEA LEVEL.
EVEN USING THE SEA LEVEL MEASUREMENT,
THAT MAKES MAUNA KEA THE HIGHEST ISLAND MOUNTAIN IN THE WORLD.
AND THAT DEFINITELY MAKES IT HIGH ENOUGH FOR COLD WEATHER,
WITH TEMPS BELOW FREEZING AND OCCASIONAL SNOW.
WHAT'S SO IMPORTANT ABOUT AN ISLAND OBSERVATORY
THAT SITS ON A MOUNTAIN?
WELL, ATOP MAUNA KEA, YOU'RE GOING UP ABOVE
OVER 40% OF EARTH'S ATMOSPHERE.
YOU'RE LITERALLY ABOVE THE CLOUDS.
NO WONDER IT'S HARD TO BREATHE.
AND AS YOU CAN SEE,
THERE ARE A LOT OF OBSERVATORIES UP HERE.
WHY?
THE THINNER AIR AT THIS ALTITUDE HAS LESS TURBULENCE,
AND LESS TURBULENCE MEANS
THAT THE IMAGES OF STARS AND PLANETS ARE MUCH SHARPER.
PARTICLES IN THE AIR
ARE WHY WE HAVE BLUE SKIES AND COLORFUL SUNSETS.
BUT CHECK THIS OUT.
TAKE AN AQUARIUM OF COOL WATER AND PUT AN EYE CHART BEHIND IT.
YOU SHOULD BE ABLE TO SEE THE EYE CHART PRETTY CLEARLY, RIGHT?
DUH, WATER'S CLEAR.
OR IS IT?
IF YOU WERE TO HEAT UP THE WATER, LIKE THIS,
NOT QUITE SO CLEAR, HUH?
SO JUST LIKE THE CLARITY OF THE WATER
HAS TO DO WITH TEMPERATURE,
SO DOES THE CLARITY OF THE SKY FOR TELESCOPES TO LOOK THROUGH.
BUT IF YOU GET ABOVE THE CLOUDS,
THE ATMOSPHERE IS GOING TO BE DRIER
BECAUSE OF THE COLDER TEMPERATURE.
SO MAUNA KEA'S PROPORTION OF CLEAR NIGHTS
IS AMONG THE HIGHEST IN THE WORLD,
SINCE THE CLOUDS STAY AT LOWER ALTITUDES MOST OF THE TIME.
ANOTHER THING THAT MAUNA KEA HAS GOING FOR IT
IS THAT IT'S ON AN ISLAND IN THE MIDDLE OF THE OCEAN,
AND EVEN ON THE ISLAND,
IT'S A GOOD DISTANCE AWAY FROM THE NEAREST CITY.
HAVE YOU EVER TRIED TO LOOK AT THE STARS
WHEN YOU WERE IN A CITY?
IT'S A LOT HARDER TO DO SO IN THAT CITY
THAN IF YOU WERE TO GO STARGAZING
IN A MORE RURAL AREA,
BECAUSE OF A LITTLE SOMETHING CALLED LIGHT POLLUTION.
HOW DO YOU KNOW IF YOU LIVE IN AN AREA WITH LIGHT POLLUTION?
WELL, ONE WAY TO CHECK IS PRETTY SIMPLE.
GO OUTSIDE AT NIGHT, LET YOUR EYES ADJUST,
AND SEE IF YOU CAN SEE THE MILKY WAY.
THAT'S THE MILKY BAND ACROSS THE SKY,
CONSISTING OF THE HUNDREDS OF MILLIONS OF STARS
THAT MAKE UP OUR OWN GALAXY.
BUT CHANCES ARE, TWO OUT OF THREE OF YOU
WON'T BE ABLE TO SEE IT.
THAT'S RIGHT; HERE IN THE U.S.,
ALMOST 2/3 OF US LIVE IN PLACES THAT HAVE LIGHT POLLUTION.
BUT UP IN A REMOTE LOCATION LIKE MAUNA KEA,
UP AND AWAY FROM POPULATED AREAS,
LIGHT POLLUTION WILL BE MINIMAL,
ALLOWING OBSERVERS TO SEE MORE CLEARLY OUT INTO SPACE.
THAT'S KIND OF THE SAME PRINCIPLE
BEHIND SPACE TELESCOPES, SUCH AS HUBBLE.
ORBITING OUR PLANET,
HUBBLE AND OTHER SPACE TELESCOPES
DON'T HAVE TO DEAL WITH OUR TURBULENT ATMOSPHERE
AND PARTICLES FLOATING AROUND IN IT,
SO THEY GET MUCH CLEARER IMAGES RIGHT FROM THE START.
BUT THERE IS A TRADE-OFF.
WHILE HUBBLE DOES GET CLEARER IMAGES,
IT'S ALSO NOT AS EASY TO MAINTAIN.
WITH THESE GROUND-BASED OBSERVATORIES,
IT'S A LOT EASIER TO GET AN ENGINEER OUT
IF SOMETHING WERE TO NEED ADJUSTMENT.
OH, AND IF YOU DO DECIDE TO VISIT MAUNA KEA,
TAKE YOUR COAT
AND REMEMBER TO WEAR YOUR SUN BLOCK,
BECAUSE WITHOUT THE PROTECTION OF THE THICKER ATMOSPHERE,
YOU WILL BE EXPOSED TO STRONG ULTRAVIOLET RAYS
THAT CAN CAUSE REALLY BAD SUNBURNS
IN A VERY SHORT TIME.
BUT, HEY, MORE ABOUT THAT ON ANOTHER EPISODE.
THAT'S ALL FOR NOW. I'M JUSTIN TULLY.
THANKS FOR WATCHING,
AND WE'LL CATCH YOU NEXT TIME ON "NASA LAUNCHPAD."