1What are photons?
Photons are light packets carrying energy.
2Blue light _____ more energy compared to red ones.
carries
3What is one of the brightest stars in our galaxy?
Eta Carinae.
4Lumonsity describes…
The total power of the star.
5What is flux?
The number of photons passing through a surface a second.
6How is flux measured?
Based on how far the star is.
7What can impact how photons arrive at your telescope?
Dectectors, atmospheric transparency, telescope imperfections, and local sources of stray light.
8How can you estimate the brightness of stars?
By comparing them to one another.
9What did Hipparchus do in 129 B.C.?
Produced the first known catalog of stars.
10What did Ptolemy do?
Created a 6 catagory catalog measuring the brightness of stars (Alamogest)
11What catalog is most compariable to the one we use today?
Ptolemy’s Alamagest catalog
12Who updated the Alamagest catalog?
Al-Battani (500 stars in 899 A.D.) and Al-Sufi (1151 stars in 964 A.D.)
13Who was the first person to introduce trig into the catalog calculations?
Al-Battani
14What did Tycho Brahes do in 1603?
Catalogged 777 stars in the Uranometria.
15What did Galileo do?
Discovered that magnitudes can describe the brightnesses of stars.
16What did Edmond Halley do?
Produced a 341 star catalog.
17What did William Herschel notice?
That measurements of stars were inconsistent with one another.
18What can photographic plates do?
Photograph nebulas.
19How many stars are catalogged today?
300 million stars as of 2006.
20What can telescope filters allow you to see?
Certain colors, wavelengths, and energies of light.