LTA Trivia Quiz for Monday, March 19, 2018 . (Sorry this report is almost a month late. I had computer problems and have just now recovered. The winners listed on the leaderboard below have their window of opportunity open for a month beginning today.)
TOPIC: Stellar Spectra
Absorption lines in the solar spectrum were first noticed by an English astronomer in 1802. In the 1800’s scientists did not know that these lines were chemical in origin.
- In 1892, Joseph von Fraunhofer studied the absorption lines of what nearby star?
- What is generally the cause of the absorption lines?
- What spectral type is our Sun?
- When we analyze the 20 brightest stars in our sky, what spectral type is the most common?
- When we analyze the 20 closest stars, which spectral type is most common?
- The Sun……JamesOn215: Our Sun is only 92 million miles way. It takes light about 8.5 minutes to cover that distance.
- The elements…….eastcoastpunx: The most abundant chemicals in our Sun are hydrogen and helium. Astronomers have discovered traces of just about every other element, too.
- Type G……Liquidhail: The seven traditional spectral types are, from hottest to coolest: O, B, A, F, G, K, M. Each of these types is decimalized, so we have, for example, A 8, A 9, F 0, F 1, and so on.
- Type A……… jellyjungle: Type A stars constitute 30% of the brightest stars we see in our sky. They are relatively bright, so they are visible over great distances, and they are not rare in our galaxy. Type B stars come in second at 25%.
- Type M…….TheVegasCloser: Type M stars apparently constitute 64% of our nearby stars. These stars are cooler, so they aren’t as bright as the other types, so they are difficult to see. Type K stars are second most common at 16%.
Leaders: make a contribution in the next 30 days to one of my charities listed and I will match your gift, up to $100. Tell the charity to contact me about your contribution.
Leaderboard posted April 10
|3/19 Winner||Number of correct answers|