Starry Heavens Newsletter
Hau’oli Nowemapa…we are flying into the busy holiday season! Here at the Imaginarium we will offer our regular programs as well as additional shows to add to your choices of “edu-tainment” in the upcoming months. In the sky and beyond, we have an upcoming meteor shower, and a very interesting milestone for a mission to a comet!
But wait, you may ask: what is the difference between a meteor and a comet? Thatʻs a good question since sometimes folks get them confused. This is partly because pictures often show them both as objects “streaking” through the sky, and meteors are also popularly referred to as “shooting stars”, which tends to confuse the issue in other ways.
A meteor starts its life off as a meteoroid, generally an inert piece of rocky debris, which varies in size. Most meteoroids are the size of a grain of sand or smaller—fragments of the either asteroids or comets. These particles drift around in space, sometimes randomly dispersed, but as in the case of meteor showers, they are left behind as a dusty trail as a comet moves through our solar system.
As the Earth revolves around the sun through the course of the year, our atmosphere collides with these meteoroids. The resulting streak is caused by the energy released as the little particle, now called a meteor, plunges through the air at speeds up to 160,000 mph. If youʻre lucky, the trail is long enough for you to catch sight of it. But a lot of times by the time you hear the “ahhhh” from someone who is lucky enough to see it, itʻs gone by the time you turn your head!
Thatʻs why meteor showers are such a great opportunity to see meteors. Generally they are a period of increased activity, although that ranges from shower to shower and year to year. In November there is a famous meteor shower called the Leonids, peaking on the evening of Nov. 17-18. Although this shower has produced some spectacular activity in the past, this year will most likely not be one of them. It pains me to get people excited about meteor showers only to tell them to not
expect a massive light show, but between the right sky conditions and peoplesʻ expectations itʻs a difficult call. However, if you are still interested, look toward the east after midnight on Nov. 17 & 18. Who knows, you may see an "ahhh" or two!
Now about comets—I will get more in depth later in this article, but contrary to some depictions comets do not “streak” across the sky like meteors, rather they appear as relatively stationary objects. They are moving of course, however their movement is over a period of days and weeks rather than in seconds like meteors. Comets are very different objects than asteroids and meteoroids.
And Now A Word From Our Sponsor...
We have a special “double feature” matinee the day after Thanksgiving (Friday, November 28)-- Magic Tree House Space Mission
at 10:00AM or One World One Sky: Big Bird’s Adventure
at 11:15AM. You may consider seeing either one or both! Either of these programs is excellent and educational and we are offering a special discount at $1 off per ticket, per show!
In addition to our Thanksgiving special, our regular programs are as follows:
Wednesday, Nov. 12 – 7:00PM
Stargazing with Krissie
(A live program)
Friday, Nov. 14 – 7:00PM
(an Imaginarium program on the evolution of stars narrated by Mark Hamill)
Wednesday, Nov. 26 – 7:00PM
(a musical experience!)
You may find more information regarding these programs on our website (http://aerospace.wcc.hawaii.edu/imaginarium.html)
or call us at 235-7350. Reservations are recommended, call 235-7433 to reserve seats.
So what about comets? Comets are different from asteroids in that they are not comprised primarily of rock and metals like asteroids. Both are defined as objects “left over” from the formation of our solar system 4.6 billion years ago, but comets have a special ingredient that asteroids do not—water. Often described as dirty snowballs, comets are thought to have brought the building blocks of life to our planet.
Comets also are found in a different part of our solar system, way out past the orbits of the gas giant planets. Out there, the sun offers no warmth and the only light is from the millions of stars as distant points. Every so often one of these cold icy objects gets pushed into an orbit that brings them toward the inner solar system, and thatʻs when things get interesting. As the comet gets closer to the sun, heat causes it to vaporize leaving a trail of gas and dust behind it. Depending on the composition of the particular comet and its distance in space relative to us--determines the duration and quality of its appearance.
All this is relevant for this monthʻs newsletter because on November 12, a mission to a comet will culminate in landing a probe on that comet to study its nucleus. The mission is named Rosetta, from the ancient stone that led to the deciphering of Egyptian hieroglyphics. Launched in 2004, this European Space Agency spacecraft has been on course to the comet with the tongue-twisting name (at least to me), 67P/Churyumov-Gerasimenko
On the way Rosetta had other duties observing two asteroids and another comet it passed by, but its primary mission is to rendezvous with 67P/C-G and deploy a Philae, a small lander named after an island on the Nile. On that island an obelisk was discovered that was the key to unlocking the mysteries of the Rosetta Stone. After landing on the comet, Philae will attach itself to the surface and remain there, transmitting data to Earth as the comet continues on its journey towards the sun.
Although not the first mission to a comet, Rosetta will be the first to orbit and land on one to study it in-situ
. As Philae and Rosetta accompanies 67P/C-G into the inner solar system, scientists hope to unlock the cometʻs ancient secrets to build upon our understanding of our own origins.
Follow Rosetta and Philae and learn more on NASAʻs contribution to this mission at https://rosetta.jpl.nasa.gov.
If you are planning on attending any of our monthly shows, we highly recommend making reservations. For reservations, please call 235-7433. As a reminder, reserved tickets must be picked up at the box office at least 15 minutes prior to showtime. If tickets are not picked up, we may sell them to patrons on the waiting list as we approach the start of the show. Additionally, credit and debit cards are not accepted at the box office
. For those that don't have reservations, we do have some tickets set aside that are sold on a first come, first served basis. I recommend arriving at the box office early if you don't have don't reservations (box office opens 30 minutes before the show begins). Please note that reservations can be made from 8am-4pm Monday-Friday. The office is not open on the weekends.
Have a great Thanksgiving!