Here is the latest article from the Astronomy site at BellaOnline.com.
Searching for Exoplanets
A number of planets orbiting stars outside the Solar System have been directly imaged, but most of the 4000 known exoplanets haven't been. Very few have been discovered by direct imaging. How do astronomers find what they can't see?
*Water on Mars*
How many claims have there been for water on Mars? I can't remember. But this water isn't on the surface, so it's more believable than some. It seems to be a lake 1.6 km under the surface. This is based on radar data collected from Mars Express.
(1) July 22, 1784: German astronomer and mathematician Friedrich Bessel was the first to determine reliable values for the distance from the Sun to another star by the parallax method.
(2) July 23, 1928: American astronomer Vera Rubin whose work on galaxy rotation rates uncovered a discrepancy between the predictions and the observations. This was early evidence of the existence of dark matter.
(3) July 28, 1635: English polymath Robert Hooke, known as “England's Leonardo”, contributed to astronomy, geology, structural engineering, chemistry and physics, helped rebuild London after the Great Fire, and was a renowned experimenter, inventor, musician and artist.
(4) August 1, 1818: American astronomer Maria Mitchell was the first American woman to discover a comet, the first to be a college professor, and the first to be elected to scientific societies in the USA.
(1) July 23, 1999: NASA's Chandra X-ray Observatory was deployed by STS-93 Columbia. Columbia was under the command of Eileen Collins, the first woman commander of a space shuttle mission.
(2) July 24, 1969: the crew of Apollo 11 returned safely to Earth. President John F. Kennedy's goal "of landing a man on the moon and returning him safely to the earth" had been achieved "before this decade is out", though he didn't live to see it.
(3) July 25, 1982: Svetlana Savitskaya became the first woman to walk in space. The Soviet cosmonaut was the first woman to go into space after Valentina Tereshkova's initial flight nineteen years earlier.
(4) July 28, 1851: the first successful photographic image of a solar eclipse, showing the Sun's corona, was made. It was a daguerrotype made by J. Berkowski at the Royal Observatory in Königsberg, Germany (now Kaliningrad, Russia).
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I wish you clear skies.
Mona Evans, Astronomy Editor