On This Date in History: The Space Shuttle program had its roots in the heads of engineers in the late 1960′s. By 1975, construction began on Columbia, the first space shuttle to fly in space. The first flight of Columbia (STS-1) came on April 12, 1981 with veteran astronaut John Young in command and Robert Crippen as pilot. After 36 orbits, the shuttle returned safely to earth and the age of the “space truck” was upon us. Part of the mission of the shuttle was to provide a vehicle to ferry cargo to and from space. Part of its mission was to help in the construction of a space station, which has come to fruition in the form of the International Space Station (ISS). One of the more noteworthy pieces of luggage taken into space was the Hubble Space Telescope, which was delivered to orbit on this date in 1990 by the Space Shuttle Discovery (STS 31).
The Hubble Space Telescope (HST) is in an orbit about 380 miles above the earth and has provided spectacular images for both the trained and amateur eye. That location provides it a huge advantage over earth bound telescopes in that it doesn’t have to deal with the earth’s atmosphere. The physics of the atmosphere results in diffraction of light and the very nature of the atmosphere is that it is in constant movement. Between diffraction and an atmosphere in motion, objects in the sky appear to jiggle and the diffraction gives the twinkling affect of stars, which results in blurred images. The HST is free some such nuisance. With a clear line of sight and a 94 inch mirror, the HST is able to provide clear images of extremely distant objects. It also can view ultraviolet and infrared light that is otherwise blocked by the earth’s atmosphere. Infrared light is a longer wavelength than visible light and is associated with cooler processes such as the formation of stars from dust clouds. The HST can see it. Ultraviolet light has a shorter wavelength than visible light and is present with very energetic events, such as exploding stars or the formation of disks around black holes. The HST can see it.
The development of the Hubble Space Telescope is as amazing as it’s namesake’s road to astronomy. Edwin P. Hubble had been interested in science and astronomy as a kid. But he was no geek. He was an accomplished athlete, having broken the Illinois State high jump record. He continued in basketball and boxing at the University of Chicago, but, as a true student-athlete, found time to get degrees in mathematics and astronomy. His academics outpaced his athletic prowess and he went on to attend Oxford University as a Rhodes Scholar. But, this is where it gets weird. He didn’t study anything related to science. Instead, he studied the law. He returned to the United States in 1913 and set up a law practice in Louisville, Kentucky. Hubble was young enough to realize that he had made a mistake and was able to do something about it. He closed down his law practice and returned to study at the Yerkes Observatory where, in 1917, he received a PhD in Astronomy. However, he chose another route after graduation rather than immediately pursuing his passion. Instead, he joined the army and served for a tour of duty in World War I.
Finally, after concluding his service to the nation, Hubble went to the Mount Wilson Observatory near Los Angeles where he went to work developing several ground breaking ideas in astronomy. He came up with a classification system for galaxies and then created Hubble’s Law, which helped determine the age of the universe and to conclude that it was expanding. Albert Einstein had already developed his theory of relativity and had concluded that gravity curved space and, therefore, it could expand or contract. But, he thought he was wrong and revised his theory. After Hubble’s work, Einstein had to correct his error and in 1931 visited Hubble for the purpose of thanking him for his work in astronomy. Hubble’s work in determining the expanding universe is the basis for the Big Bang Theory.
As great as the HST has been, nothing lasts forever. The HST was designed for servicing and at least 4 service missions from the space shuttle have been undertaken. Perhaps the most famous was when the Space Shuttle Endeavor (STS-61) came to the rescue with corrections to a flawed mirror that messed up the optics. In February 1997, Discovery (STS-82) came to do some work and Discovery again returned in late 1999 (STS 103) and replaced the gyroscopes. A few years later in 2002, the last of the original instruments on the HST was replaced with some new hardware courtesy of Columbia (STS-109). In May 2009, most likely the final service mission to the Hubble Space Telescope took place with a visit from Space Shuttle Atlantis (STS-125). The crew of Atlantis replaced numerous instruments and parts and put the HST in an orbit that should keep it aloft until sometime between 2019 and 2032. It was originally designed to be brought back to earth in a shuttle but the program has been cancelled and the shuttle fleet will be retired soon. So, the HST will be allowed to die a quick and undigified death with an orbital decay that will eventually end with it being burned to a crisp. Maybe that’s not all bad. It came in a blaze of glory and will go out the same way, when it gives way to the James Webb Space Telescope. I’m sure that it will be outstanding…but you can never duplicate the first time.
Weather Bottom Line: I’ve been talking of the risk of severe weather for this weekend and it’s here. I have to admit some of the numbers coming through are showing something potentially a little more formidable than even what I expected. Every time that I’ve seen a SWEAT index over 500, something exciting happens. The models are not in full agreement on this issue but they are close. The RUC at 5Z was coming in with a SWEAT index of about 502 for 6 pm on Saturday. The NAM has about 424 for around that time and the GFS is at 491. CAPE for the NAM top out around 905, the RUC at 1521 and the GFS is more subdued at 406. The Lifted Index is -3.2 for the NAM, -1.4 for the GFS and the RUC goes bananas at -6.1. Helicity for NAM is 840 and 600 for the RUC while the GFS is negligible but I have to believe that its just crappy data.
So, what does this say. Guarantee for a widespread severe outbreak? No, but there is a pretty fair chance for numerous reports. Now, the timing of this with all three models is about 6-8 pm….closer to 6-7 pm. You’ll note that the SPC has the highest probability (45%) of the type of severe weather in our area for wind. The best chances for tornadoes will be well to our south in the Heart of Dixie. But, if this stuff…perhaps a lead super cell…comes moving through the flow in the afternoon during the heat of the day, it’s not out of the question for there to be enough dyamics to produce a twister or two. Best chance for that still seems to be from say Owensboro to Bowling Green and points to the Southwest. A concern that I may have would be for areas to the northeast of that…say toward Springfield or Lebanon. I would think that Lexington will be too far northeast.
I would get yardwork done early in the day. We’ll probably warm up nicely with breezy conditions. Isolated t’storms will start to float through in the early afternoon with more numerous cells by the end of the day. Any storms that show up in the afternoon should be taken note of as it will have the potential for some monkeybusiness. As we get toward sunset and after, be aware of the potential for strong winds as storms may be collapsing. Even before then, storms will be racing along and their sheer momentum will produce strong winds in addition to downbursts. Hail will also be a possibility but straight line winds will be the focus of concern followed by tornadoes. Typically, when we get to the evening hours, these types of situations evolve into one of line segments. When/if that happens, then there will be the potential for wind along bow echoes as well as isolated, short lived tornadoes on the edge of the apex of a bow segment. Actually, I believe this type of situtation is the more common derivation of tornadic activity in our area rather than super cells.
Rain totals are showed to be at about 1.5 inches by early Sunday morning for the NAM, 1.25 inches for the GFS. The 5Z RUC only goes out to 6pm so it’s inconclusive but my guess is that it will be coincidental with the other two. The axis of the main low will be just to our east on Sunday as this guy really gets bogged down. But, we will still be in the influence of the system such that we can expect slightly cooler but still wet conditions on Sunday with passing showers in the picture. I believe the GFS even wants to hold the rain chances over into Monday. The threat of severe weather though will have gone by the way side by around Midnight Saturday night.