PHASE-TASTIC!
(Part 2)
JAMES: WELCOME TO STARGAZERS!
I'M JAMES ALBURY, DIRECTOR OF THE KIKA
SILVA PLA PLANETARIUM IN GAINESVILLE, FLORIDA.
DEAN: AND I'M DEAN
REGAS, ASTRONOMER FROM THE CINCINNATI OBSERVATORY.
YOU MIGHT REMEMBER THAT
TWO WEEKS AGO, JAMES ASKED ME A QUESTION ABOUT
WHAT PHASE THE MOON WOULD BE
IN IF IT ROSE AT NOON.
JAMES: YUP! AND YOU GOT IT RIGHT TOO.
DEAN: YES I DID!
SO, I HAVE A QUESTION FOR YOU.
ARE YOU READY?
JAMES: SURE!DEAN: OK, IF THE MOON SETS AT
NOON, WHAT PHASE
IS IT IN?
JAMES: AH!
IT WOULD BE AT LAST QUARTER.DEAN:
EXCELLENT!
JAMES : THANK YOU, THANK YOU!
OOO!
THAT REMINDS
ME OF A MOON JOKE.
DEAN: UH MAYBE SAVE IT FOR LATER,
JAMES.
JAMES: YAY!
SO, WE'LL SHOW YOU HOW I ANSWERED
THAT QUESTION AND WE HAVE A REALLY COOL CONJUNCTION
OF JUPITER AND MERCURY
AT THE END OF THIS WEEK AND THE MOON JOINS
THE TY RIGHT AFTER NEW YEARS!
LET'S SHOW YOU!
JAMES: WHEN WE TALKED TWO WEEKS
AGO ABOUT THE PHASES OF THE MOON, WE MENTIONED
THAT IT TAKES ABOUT A WEEK
FOR THE MOON TO GO FROM ONE MAJOR PHASE TO
THE NEXT.
FOR EXAMPLE,
IF THE MOON IS IN THE NEW PHASE ON DECEMBER
7TH, IT WILL BE AT FIRST QUARTER
ON DECEMBER 15TH.
DEAN: WHEN THE MOON IS AT FIRST QUARTER, IT'S
TRAVELED A QUARTER OF THE WAY AROUND THE EARTH
AND THEREFORE, IT'S 90 DEGREES
EAST OF THE SUN IN THE SKY.
SO, THE MOON RISES JUST AS THE SUN REACHES
IT'S HIGHEST POINT IN THE SKY AT NOON.
JAMES: THEN, A WEEK
AFTER THAT, ON DECEMBER 22ND, THE MOON IS
IN ITS FULL PHASE, AND IT'S 180 DEGREES
AWAY FROM THE SUN.
THIS MEANS THAT THE MOON WILL RISE AS THE
SUN SETS,
AND IT WILL SET AS THE SUN RISES.
JAMES: IN THE
DAYS FOLLOWING THE FULL MOON, WE BEGIN TO
SEE LESS AND LESS OF THE DAYTIME SIDE
OF THE MOON AND MORE AND MORE OF THE NIGHTTIME
SIDE.
THESE ARE CALLED
THE WANING PHASES.
WANING MEANS TO GET SMALLER, AND THE MOON
IS APPEARING
HUMPED AGAIN, SO WE CALL THIS THE WANING GIBBOUS
MOON.
DEAN:
ON DECEMBER 29TH IT WILL HAVE BEEN A WEEK
SINCE THE FULL MOON AND THE MOON HAS
TRAVELED THREE QUARTERS OF THE WAY AROUND
THE EARTH, SO WE CALL THIS PHASE LAST
QUARTER.
WE AGAIN SEEHALF OF THE DAYLIT SIDE AND HALF
OF THE NIGHTTIME
SIDE, BUT REVERSED FROM WHAT WE SAW AT FIRST
QUARTER.
THE MOON IS ALSO
VISIBLE IN THE EARLY MORNING INSTEAD OF THE
EARLY EVENING.
JAMES:
IN THIS CONFIGURATION, THE MOON IS NOW 90
DEGREES WEST OF THE SUN.
SO WHEN THE
SUN IS AT ITS HIGHEST POINT IN THE SKY AT
NOON, THE MOON WILL BE SETTING ON
THE WESTERN HORIZON.
DEAN: LASTLY, WE HAVE THE WANING CRESCENT
PHASE.
THIS OCCURS DURING THE LAST WEEK OF THE MOON'S
ORBIT AROUND THE
EARTH AND WE SEE THE DAYLIT SIDE SHRINK MORE
AND MORE AS THE DAYS PASS.
JAMES: ON JANUARY 5TH, 29 DAYS AFTER THE BEGINNING
OF THE MOON'S JOURNEY,
THE MOON IS BACK WHERE IT STARTED, IN A POSITION
PUTTING IT BETWEEN THE EARTH
AND THE SUN.
THE MOON IS NEW ONCE AGAIN.
HEY DEAN, CAN I TELL MY JOKE
NOW?
DEAN: GO AHEAD, JAMES.JAMES: OK, HOW DO YOU
KNOW
WHEN THE MOON HAS GONE COMPLETELY BROKE?DEAN:
HMMM I DONT
KNOW
JAMES, HOW?
JAMES: ITS DOWN TO ITS LAST QUARTER!
HA!
DEAN: TOTALLY WORTH
THE WAIT!
DEAN: OK, WE
HAVE OUR SKIES SET UP FOR DECEMBER 21, AN
HOUR BEFORE SUNRISE, FACING SOUTHEAST.
LOW ON THE HORIZON YOU'LL SEE THREE STARS
MARKING THE FACE OF SCORPIUS THE SCORPION
AND JUST BELOW THEM YOULL SEE ANTARES, THE
SCORPIONS HEART.
TO THE LEFT
OF THAT, YOU'LL SEE JUPITER AND MERCURY.
JAMES: THE TWO PLANETS
WILL APPEAR AT THEIR CLOSEST THAT DAY AND
THEY'LL BE LESS THAN A FULL MOON WIDTH
AT.
DEAN: MERCURY IS A SPEEDY PLANET, SO THIS
CONJUNCTION WON'T
LAST LONG.
IF YOU MISS SEEING THEM THAT MORNING, MAKE
SURE YOU CHECK THEM
OUT ON DECEMBER 22ND AND 23RD.
THEY'LL BE A LITTLE FURTHER AT, BUT STILL
AN IMPRESSIVE SIGHT.
JAMES: THEN, A WEEK LATER, THE WANING CRESCENT
MOON JOINS THE PARTY; PASSING BY VENUS ON
JANUARY 1ST AND THEN JUPITER ON JANUARY
3RD.
DEAN: SO THERE YOU HAVE IT, THE PHASES OF
THE MOON AND A WONDERFUL
PAIRING OF PLANETS TO END 2018.
JAMES: ITS ALL WAITING FOR
YOU WHEN YOU BOTH: KEEP LOOKING UP!