Blue Star Questions
Name: rachael mccullough
Date: 1993 - 1999
Is it true that blue stars are the hottest? If they are then how can
you tell the difference between a very hot(almost whitish blue) star and a white
star? In my magazine Natural History, It said that it is possible to see Saturn,
Jupiter, and mars. I have seen Venus she is very easy to spot. Do you have any t ips on
spotting the others without a telescope? Do you know when the next blue moon
WHERE IS JACK HORKHEIMER WHEN WE NEED HIM?!?!?! sorry about that..
Jack does a 5 minute fill spot for amateur astronomers that is broadcast on many
PBS TV stations; he lives for questions like these. as for observing the
planets, look for bright stars that don't twinkle, also, Mars is reddish (extra- credit: why do stars
twinkle but not planets?)
Check out Astronomy and Sky & Telescope magazines (often available at
the public library) for directions on where to look for the planets
month-by-month. At this time (early February) Venus and Jupiter can be seen in
the predawn sky (Jupiter rises around 3:15 am, Venus about an hour later). Mars is the easiest to find; it
rises right about sunset, stays up all night, and is bright and notably reddish.
Saturn is in the southwest at sunset and currently sets around 8pm (I haven't
been out at the right time to look for it lately, so I don't know how easy it is to spot). Mercury
is currently in the glare of the sun, so it can't be seen with the naked eye. It
is seldom easy to spot anyway, you usually have to know just where to look.
The expression "once in a blue moon" means "very seldom". It is not a regular
occurrence. According to Jearl Walker's book "The Flying
Circus of Physics", the moon can appear bluish when the upper atmosphere
contains dust from a volcanic eruption, or smoke from a forest fire, with
particles of a size that preferentially scatter light from the red end of the
spectrum, leaving the remaining light relatively enriched in blue.
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Update: June 2012