Yes, there are two Americas’ Virginia, they exist as certainly as love and generosity and devotion exist. One tolerant and broadminded, the other intolerant and narrow-minded!
Sincerely, thinkingblue, from the TOLERANT AND BROADMINDED USA
PS: Joe (You Lie) Wilson, et al reside in the other America!
Thursday, March 21, 2013
So many questions, so little time.
goodness for The Internet (and those who use it thoughtfully)
which tries to answer the many questions we have from time to
time about existence. If only technology had advanced a bit
quicker, perhaps we, the Hoi Polloi, would be so much the wiser.
have a question from our young friends at the Mountain Home Air
Force Base Youth Activities Center in Mountain Home, Idaho. They
wonder how many solar systems are in our galaxy. Well, I wish I
knew the answer to this thought-provoking question, but not only
do I not know, no one does. Even so, this question brings up some
many years scientists have studied our own solar system. But
until the last few years, we knew of no other solar systems.
may seem surprising, as the Sun is one of about 200 billion stars
(or perhaps more) just in the Milky Way galaxy alone. With all
those other stars, why haven't scientists studied other solar
systems, at least enough to know how many are in our galaxy?
regular visible light telescopes, planets are very hard to see in
the glare of a star. Using infrared space telescopes, the planets
shows up much more clearly.
the reason is that planets around other stars are really hard to
find. Planets shine only by the light they reflect from the star
they orbit, and they don't reflect much light at that. And the
stars, along with any planets under their control, are so far
away that picking out a faint planet near a distant star is like
spotting a mosquito next to a brilliant searchlight miles away.
Rayman at age 14 meets astronomer Peter van de Kamp (center), who
had "discovered" planets outside our solar system. On
the right is radio astronomer Grote Reber. (Image from Sky and
Telescope, Aug. 1971.)
although scientists, philosophers, writers, and people like you
who have been fascinated by the universe have thought about other
solar systems for centuries, they haven't had any to study. When
I was young, this was one of many topics that I spent a great
deal of time wondering about. In fact, when I was in the ninth
grade, I was lucky enough to meet an astronomer who thought he
had detected two planets around Barnard's Star, one of the
closest stars to our solar system. It was quite a thrill for me
to meet someone involved in such exciting work. Alas, later
evidence suggested his conclusions were incorrect, but I learned
a great deal about the subject, as well as about the scientific
method, by studying what this impressive astronomer had
in the middle 1990s, astronomers found strong evidence of planets
around other stars. In all cases, they found the planets not by
taking pictures of them, but rather by detecting their
astonishingly gentle tugs on the stars they orbit. Although the
star holds the planet tightly in its gravitational grip, the
planet also exerts a gravitational pull back on the star, and
that is what astronomers measure. It amounts to seeing the star
wobble back and forth very slightly as the planet completes each
orbit. Learn more about this gravitational dance as you try to
solve the extraterrestrial
that, astronomers started detecting planets through several other
methods as well. For example, if the orbit of a planet happens to
be aligned so that planet occasionally travels in front of the
star from our perspective on Earth, it blocks some of the light.
Even though the planet is tiny compared to the star, extremely
sensitive instruments can measure the tiny change in brightness.
NASA's Kepler mission used this technique to identify hundreds of
stars that may have planets. Astronomers are observing these
stars more carefully to confirm the presence of the candidate
is working on more space missions that will allow scientists not
only to find other solar systems but also to study the planets
there in greater detail. Some of the intriguing questions these
missions might help answer are how common are other solar
systems; is our solar system typical, with giant planets like
Jupiter and smaller ones like Earth; how do solar systems form
and evolve; are there other planets capable of supporting life;
and is there life on other planets?
shows a steaming hot (with water!) planet discovered in another
So far, astronomers have found more than 500 solar systems and
are discovering new ones every year. Given how many they have
found in our own neighborhood of the Milky Way galaxy, scientists
estimate that there may be tens of billions of solar systems in
our galaxy, perhaps even as many as 100 billion.
Whether this estimate is correct and how similar other solar
systems are to ours, remain to be seen. It has only been a few
years since the first solar system apart from ours was detected,
and they are still extremely difficult to study, so this whole
subject is still in its infancy. By the time our friends who
asked the questions are adults, we will know a great deal more.
Perhaps someday you will help find the answers. And even if
you don't, you may grow up in a time when humankind has a much
clearer idea of how we and our home planet fit into the cosmos.
Yes, there are two Americas’ Virginia, they exist as certainly as love and generosity and devotion exist. One tolerant and
free-thinking, the other intolerant and close-minded!
Sincerely, thinkingblue, from the TOLERANT AND FREE-THINKING USA
PS: Joe (You Lie) Wilson, Glenn Beck, Sarah Palin, Rush Limbaugh et al reside in the intolerant America!