Wednesday, May 19, 2004 |
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Transit of Venus  As the Sun rises here in Connecticut on Tuesday morning, the 8th of June, an event so rare that nobody alive today has observed it will be underway. Our sister planet, Venus, will be seen (weather permitting) crossing the face of the Sun. This phenomenon is known as a Transit of Venus. These transits happen in pairs eight years apart and then more than a century passes till the next one. The last Transit of Venus happened in 1882, the next will occur in 2012, and then there will be no more until the year 2117. Before going any further, YOU MUST BE WARNED THAT LOOKING DIRECTLY AT THE SUN WILL DAMAGE YOUR EYES AND LOOKING AT THE SUN WITH BINOCULARS OR A TELESCOPE MAY CAUSE INSTANT BLINDNESS IF THE INSTRUMENT IS NOT PROPERLY FILTERED. There are safe methods of observing the Sun and they can be found on the web sites listed below. The transit of June, 2004 will be only the 6th time this event has been observed, that we know of. The first was observed by the young and very talented British self-taught astronomer, Jeremiah Horrox, in 1639. The angular size of Venus during a transit is about 1 arc-minute (just on the limit of visibility for the unaided human eye; remember you need a proper filter and sunglasses are not nearly good enough) and the apparent diameter of the Sun is about 30 times bigger or about half a degree. Transits of Venus have scientific value and a rich history. In 1678 Edmond Halley (of comet fame) suggested that a transit of Venus observed from well-separated sites on Earth would be the best way to determine the all-important value of the astronomical unit - the average distance from the Sun to the Earth. This led to the fantastic voyages of transit expeditions that went to the ends of the Earth in the eighteenth century and the more scientific expeditions in the nineteenth century. Transits of Venus also have a rich cultural heritage associated with them, including art, literature, poetry, and music. John Philip Sousa wrote a Transit of Venus march. The image above is Venus the way it looked on the evening of 16 May 2004, just 22 days before the Transit. It was taken through the 16-inch reflecting telescope of the McCarthy Observatory with a CCD camera and a blue filter. Since Venus is closer to the Sun than the Earth is, it goes though phases just like our Moon. Venus is now the bright 'star' in the western sky as it gets dark. Because Venus is closer to the Sun than Earth, its speed in orbit is faster than ours; so Venus is passing the Earth and will continue to get lower and lower in the sky as the time of transit approaches. The McCarthy Observatory is planning a wide range of activities for transit day. Weather permitting we will broadcast the event live on the local public access channel, Channel 17. Stay tuned to this web site for further information on the transit and our public outreach activities. Call the observatory if you have questions; 860 354-1595. For more information consult these excellent sites: http://www.vt-2004.org/index.html and http://www.transitofvenus.org/ Click to return to the table of contents Comet C/2001 Q4(NEAT) The JJMO is hosting a comet watch on Friday, May 14. Comet C/2001Q4 (NEAT) has emerged into the northern skies and is heading away from the sun. This comet's discovery occurred as a result of JPL's organized search for near earth objects in 2001. The comet appeared on May 10 due south of Procyon and is plotted to move through the Bee Hive cluster (May 14, 15) and on to Ursa Major and into Draco by the end of May. If the sky clears up, we will be treated to a nice view of one of this year's best comets. Click to return to the table of contents Astronomy Day 2004 Was A Great Success The sun was bright and clear on Saturday, April 24. The volunteers of the JJMO had set up a number of telescopes and displays on the New Milford green. The telescopes gave Saturday shoppers and strollers a chance to watch a pair of sun spots march across the disk of the sun. A photo display highlighted some of the neat things in the sky and included two panoramas of Mars that showed everyone how much nicer it is to be here, rather than there. Later in the day, toward twilight, the observatory opened up. Telescopes and binoculars were trained first on the moon, then Venus, then Jupiter and finally Saturn as day dimmed into night and each object magically appeared above us. Shrieks of Cool!, Wow! and Neat! exploded from the children. Hushed murmurs of awe occasionally were heard from their more reserved parents. What a great day it was! We would like to thank the public for its support. We would also like to offer an invitation. When the night sky is achingly clear and when the stars seem to be so close that they can be plucked out of the sky like cherries, come and visit us. We’ll be waiting. Click to return to the table of contents JJMO Reports its First Asteroid Discoveries Three new asteroids were discovered from site 932 during follow-up observations of the newly discovered Potentially Hazardous Asteroid and Virtual Impactor 2003 TH2, early on October 14, 2003. Two of these were reported, that night, to the Minor Planet Center (MPC) with the site's temporary designations of AQXZQZW and BQXZQZW. If the third asteroid can be re-acquired, further data will be taken and the full set of astrometry data for the third target will be forwarded to the MPC for review. The MPC has given AQXZQZW the Provisional Designation 2003 TG10 and BQXZQZW has been designated 2003 TH10. These discoveries will be credited to the John J. McCarthy Observatory since there were more than two individuals listed as observers in the report to the MPC. The two new asteroids appear to be normal main asteroid belt objects, 2003 TG10 was magnitude 18.4 and TH10 was magnitude 18.3. Locating and observing Near Earth Asteroids is a key activity at the JJMO, that requires the coordinated output from the telescopes and imagers. Astronomical Image Processing Astrometry Software, compares the data from the imagers to the star catalog of the USNO A-2.0 data base to determine the coordinates of the target asteroid. The asteroid’s position at the exact time of observation is then sent to the MPC for review. The Near-Earth Dynamic Site now lists 106 NEA observations from the JJMO. All 106 observations have been used to help refine the orbits of these asteroids. Further detail on 932’s submissions to the MPC for NEO asteroids can be found at http://newton.dm.unipi.it/cgi-bin/neodys/neoibo?sites:932;main Click to return to the table of contents |
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JJMO Repeats Flamsteed's Measurement of the AU John Flamsteed, Britain’s first Astronomer Royal, developed a procedure to determine the value of the astronomical unit (AU) and accomplished the task in Derby, England on the night of 6 October 1672. Flamsteed labored at the telescope for over six hours, measuring the angular separation between Mars and 'three little stars' in the constellation Aquarius, with a micrometer attached to the eyepiece. He was looking for the elusive parallax of Mars. Parallax is the apparent displacement of an object’s position compared to a more distant background when viewed from different sites. Knowing the parallax angle and the distance between sites, the baseline, triangulation produces the distance to the target. The rotating Earth would provide a baseline distance for his calculations since he and his telescope were seeing Mars from a different vantage point after six hours. Parker Moreland and his team duplicated Flamsteed’s work on their third attempt since the August 28 opposition of Mars, on September 16 and 17, 2003. At 8:31 PM EDT on both nights, the measurement team (Parker Moreland, Monty Robson, Amy Ziffer, and Sheila McMahon) used a micrometer eyepiece and the observatory's Takahashi 106mm telescope to measure the distance from Mars to a nearby, magnitude 7.3 star, to the nearest arc-second. They measured the distance again six hours later at 2:31 AM EDT on both nights. Parker’s team combined Kepler's Laws of planetary motion with the properties of elliptical orbits and used the combined data from both sets of observations to calculate the parallax, the distance to Mars and the Astronomical Unit (AU). Preliminary analysis of the data revealed that the Mars parallax was 22.8±4.0 arc-seconds, the distance to Mars the night of the 16th was ~38 million miles, and the Astronomical Unit works out to be 93.4 million miles. These values compare very well with simulated measurements made using the JPL HORIZONS Ephemeris data of Mars’ position and with the now well established value of the Astronomical Unit. Click to return to the table of contents Mars Mania Mobs the McCarthy Observatory  The Mars encounter on August 27 was attended by over 400 people from the community. Telescopes were out and running, there was a line of people outside of the observatory who were eager to get a glimpse of Mars from the main telescope. A video feed was hooked up from the Takahashi mounted Astrocam and a monitor was placed outside for viewers to watch while they waited. Bill Cloutier brought his 10 inch Dob, Monty, his 8 inch Celestron, and John Gebauer, his 5 inch telescope. The new 15 x 70 binoculars were set up on the binocular stand. Initially cloudiness reduced the quality of the viewing, but by 10:00 pm the seeing conditions were outstanding. The polar cap and various surface features were clearly visible from the 16 inch Meade. Those who attended the event came away with a strong appreciation for the facilities of the JJMO. Click to return to the table of contents JJMO Studies Potentially Hazardous Objects  The JJMO staff and students at New Milford High School are fully engaged in one of the McCarthy Observatory's primary science missions: observing, precisely measuring the position of, and helping validate the orbits of newly-discovered Potentially Hazardous Objects. These objects are asteroids that professional watchers have determined may have orbits that bring them dangerously close to the earth at some future date. Our first observations were of asteroid 1620 Geographos. In early April of 2002, we imaged 2002 FU5, and JJMO was one of only 14 observatories in the world that succcessfully imaged and measured it's location to the required precision. To date, JJMO has submitted 21 observations of potentially hazardous asteroids as dim as magnitude 18.4, and have 100% of our measurements accepted. We will continue to expand this collaboration with the IAU Minor Planet Center, JPL and NEODyS. Click to return to the table of contents Ring Nebula (M57) Imaged at JJMO  An amazing object for sure, and one of the top 5 nebulae that amateur astronomers try to discern through their telescopes. Here Jeff Tarvin imaged the object and Randy Fender did the digital processing to create this stunning view. The Ring Nebula or M57 (Messier object # 57) is what happens to a star about the mass of our own sun that nears the end of its life. The ring is actually the result of the star losing its gaseous shell outward at approximately 16.5 miles per second. We are viewing this object, which is 1100 light years away, and the event occurred about 20,000 years ago. In about 5 billion years our own sun will meet the same fate. Click to return to the table of contents |