Friday, December 26, 2014
YOLO COUNTY NEWS
99 CENTS

Explorit: Twinkle, twinkle, little star, how I wonder what you are

By
From page A5 | September 13, 2013 |

By Vinita Domier

Ever wonder how astronomers determine physical properties of distant stars such as their chemical composition, surface temperature, luminosity, etc.? How they infer the speeds of stars and galaxies relative to the Earth? Or how they calculate the vast distances of stars and galaxies from the Earth?

If so, then please come to the Davis Astronomy Club’s next free meeting on Saturday at Explorit Science Center, 3141 Fifth St. in Davis, starting at 7 p.m., for a presentation on some of the observational techniques that astronomers use to answer these and other fundamental questions about the universe. All ages are welcome to attend the featured presentation indoors, followed by the star party outdoors.

Starlight emanating from a star’s extremely hot and dense photosphere produces a continuous spectrum of visible light when dispersed through a spectroscope. When this light passes through the relatively cooler and less dense gasses enveloping the star’s surface, dark lines appear in the continuous spectrum. There are more than 600 distinct dark lines in the sun’s visible spectrum.

The chemical composition of the star’s cooler gasses can be determined by comparing the dark line patterns in its spectrum to the signature patterns produced in the laboratory by the 92 naturally occurring elements in their neutral and ionized states. The chemical make-up of the star’s interior can then be surmised to be similar to its surface, with the thickness of the lines indicating relative proportions of the elements.

Dark spectral lines also indicate stellar surface temperatures as elements ionize at different temperatures. The absence of dark lines of elements in stars can mask the fact that the elements do exist, but are in a completely ionized. If the temperature of a star exceeds an element’s ionization temperature, that element can still exist in the star even though it does not produce dark lines. Visual colors of the stars also indicate their temperatures, with blue stars being hottest and red stars being coolest.

Join us Saturday to find out more about spectral analysis and the wonders of the galaxy.

————

Explorit events:

Saturday, Oct. 19: You’re invited to our October fundraiser “Touched by Science, Touched by Explorit Celebrating 30 Years of Putting Hands On Science,” from 5:30 to 8 p.m. Enjoy food, wine, special guests and get your own commemorative long-STEM wine glass! Explorit members and UC Davis Alumni Association members can purchase discounted tickets to this fundraiser. For more information and to buy tickets, visit http://www.brownpapertickets.com/event/437033.

— Explorit Science Center is at 3141 Fifth St. For more information, call 530-756-0191, visit http://www.explorit.org or “like” Explorit on Facebook at www.facebook.com/explorit.fb.

Comments

comments

Special to The Enterprise

  • Recent Posts

  • Enter your email address to subscribe to this newspaper and receive notifications of new articles by email.

  • .

    News

    Transit survey: 47 percent ride bikes to UCD campus

    By Special to The Enterprise | From Page: A1 | Gallery

     
    Exchange students bring the world to Davis

    By Anne Ternus-Bellamy | From Page: A1 | Gallery

     
    Pastor has many plans for CA House

    By Jeff Hudson | From Page: A1 | Gallery

    Playing Santa

    By Enterprise staff | From Page: A2 | Gallery

     
    Goats help recycle Christmas trees

    By The Associated Press | From Page: A2 | Gallery

     
    Special holiday gifts

    By Sue Cockrell | From Page: A3

    Woodland-Davis commute bus service expands

    By Enterprise staff | From Page: A3

     
    Learn fruit tree tips at free class

    By Enterprise staff | From Page: A3

    Davis Bike Club hears about British cycling tour

    By Enterprise staff | From Page: A3

     
    Pick up a Davis map at Chamber office

    By Enterprise staff | From Page: A3

    Sierra Club calendars on sale Saturday

    By Enterprise staff | From Page: A3

     
    Explorit: Get a rise out of science

    By Lisa Justice | From Page: A4

    NAMI meeting offers family support

    By Special to The Enterprise | From Page: A6

     
    Yoga, chanting intro offered

    By Enterprise staff | From Page: A8

    .

    Forum

    Blamed for her sister’s rage

    By Creators Syndicate | From Page: B5

     
    How much for the calling birds?

    By Creators Syndicate | From Page: B5

    Steve Sack cartoon

    By Debbie Davis | From Page: A10

     
    Many ensured a successful parade

    By Letters to the Editor | From Page: A10

     
    Thanks for putting food on the table

    By Letters to the Editor | From Page: A10

     
    .

    Sports

     
    Two more for the road for 9-1 Aggie men

    By Bruce Gallaudet | From Page: B1 | Gallery

    Patterson is college football’s top coach

    By The Associated Press | From Page: B1 | Gallery

     
    Clippers get a win over Golden State

    By The Associated Press | From Page: B1 | Gallery

    NBA roundup: Heat beat Cavs in LeBron’s return to Miami

    By The Associated Press | From Page: B10 | Gallery

     
    .

    Features

    .

    Arts

    ‘Unbroken': A bit underwhelming

    By Derrick Bang | From Page: A11 | Gallery

     
    Folk musicians will jam on Jan. 2

    By Enterprise staff | From Page: A11

    .

    Business

    Passat: Roomy, affordable sedan with German engineering

    By Ann M. Job | From Page: B3 | Gallery

     
    .

    Obituaries

    James J. Dunning Jr.

    By Special to The Enterprise | From Page: A4

     
    Floyd W. Fenocchio

    By Special to The Enterprise | From Page: A4

    .

    Comics

    Comics: Friday, December 26, 2014 (set 2)

    By Creator | From Page: B7

     
    Comics: Thursday, December 26, 2014 (set 1)

    By Creator | From Page: A9