Each year of this closing decade brought at least one memorable astronomical event. Nearly everyone remembers something outstanding, such as the unusually close approach of Mars, the Venus transit, Comet Holmes, or one of the lunar eclipses. The official decade runs from January 1, 2001 through December 31, 2010, but somehow it seems more appropriate to look at the years from 2000 to 2009. The following are considered the most significant and memorable celestial events of the past ten years.
2000: The year started out with a frigid total lunar eclipse on the evening of January 20 that produced a beautiful coppery Moon visible even with an occasional light snow falling in the 5ºF cold. The summer featured Comet LINEAR appearing like a tiny white tornado passing below the Big Dipper during July. The year ended with a dramatic partial eclipse of the Sun on Christmas Day. The Sun was 60% eclipsed above a snow covered world shortly after noon with the temperature hovering just above 0ºF.
2001: Mars made a very close approach to Earth during June, but this opposition was memorable because a global dust storm obliterated all hope of seeing any surface detail that summer. July featured a visit from a different Comet LINEAR as it passed near Pegasus appearing like a cotton ball. The Leonid meteors stormed on the morning of November 18 with 537 seen in 2½ hours before dawn broke and several were even seen after that in bright twilight. Still another Comet LINEAR was seen from November into December as it dropped into Cetus and developed a bright stubby tail. Within minutes the very swift movement of asteroid 1998 WT24 was observed when it passed unusually close to Earth on December 15.
2002: Spring started off with beautiful Comet Ikeya-Zhang, which was visible into June. It was the best Comet since Hale-Bopp with a beautiful tail as it climbed out of the northwest evening skies near M31 and passed overhead before fading in June in Serpens Caput. A slight partial eclipse of the Sun before sunset on June 10 was marred by thick haze and high clouds along the horizon. Asteroid 2002 NY40 made a close flyby of Earth during the evening of August 17; its swift motion among the stars was obvious. Comet Hoenig was seen during Labor Day weekend as a ghostly glowing fuzz ball. A beautiful aurora flared up during the MVAS star party on September 7 dazzling all.
2003: A total eclipse of the Moon on the evening of May 15 was clouded out. The marquee event of the decade was the unusually close approach to Earth in nearly 60,000 years by Mars during late August, which treated observers to incredible views of surface detail for months. The author spoke on WIBX radio about the opposition and promoted a public Mars observing event at Lee Town Park on the evening of August 30 that drew over 300 people and lasted well past midnight. Beautiful green and pink displays of the Aurora Borealis were seen very briefly on the evening of October 30. A very short and unusually bright total eclipse of the Moon was observed during the evening of November 8.
2004: Venus was observed in the daylight during the late afternoons in late April. Two comets, NEAT Q4 and LINEAR T7, were seen at the same time during several evenings in late May. NEAT Q4 had a beautiful tail when it was near the Beehive Cluster in mid-May and LINEAR T7 had a long, narrow tail in Hydra. The awesome transit of Venus was visible at sunrise on June 8 under delightfully clear and warm skies. Comet LINEAR K4 appeared in the evening in June and was seen into August as it developed a small tail while passing through Bootes and past Arcturus. A beautiful total eclipse of the Moon was seen during the evening of October 27 looking like the Great Pumpkin with its orange glow along with several meteors leaving smoke trains. A busy year ended with Comet Machholz appearing like a beautiful delicate flower of radiating streamers during the Christmas season near Orion.
2005: Comet Machholz started off the year near the Pleiades but lost the streamers as it appeared like a bright fuzzy ball in March as it passed Polaris and then faded rapidly. A beautiful triple conjunction between Mercury, Venus, and Saturn all within a wide-angle telescope field was seen during late June. A bright solar flare was observed through hydrogen alpha telescopes on September 10 and later that evening there was a beautiful aurora. Mars made another fairly close approach to Earth around Halloween. Its placement high in the night sky delighted observers with impressive views of the red planet once again.
2006: This was another big year for comets as Comet Schwassman-Wachmann 3 with a beautiful tail was seen during April in Corona Borealis. Comet SWAN was seen on October 30 in Hercules also with a beautiful tail, but it faded dramatically in November. The transit of Mercury across the Sun on November 8 near sunset was clouded out. Comet Faye was seen later in November as nothing more than an extremely faint ghostly glowing ball, almost at the limit of visibility.
2007: A total eclipse of the Moon at sunset on March 3 was clouded out. Venus was seen as a huge and slender 1%-3% lit crescent before sunset during several evenings in late July and early August. A partially eclipsed Moon was seen setting shortly before sunrise on August 28. Comet Holmes appeared dramatically in late October like a brilliant yellowish-green cotton ball with a compact coma and bright nucleus. The coma expanded into a huge glowing ball in November with a hint of a tiny tail as it moved through Perseus and gradually faded into the winter.
2008: A beautiful total eclipse of the Moon was observed on the evening of February 20 in a perfectly clear sky, but only during the time of totality, a rare twist of fate. The Moon was a clean orange with some blues and grays. This was the only event of the year, the quietest year in the 10-year period.
2009: The International Year of Astronomy. Comet Lulin kicked off this historical year as it was seen in the evening near Saturn and Regulus during the end of February. Venus was seen just before sunset on March 27 hardly 1% lit with the crescent displaying an extension of its cusps only two days before inferior conjunction. The Pleiades, Mercury, and a thin crescent Moon made a beautiful, close grouping during the evening of April 26. Jupiter was seen with no moons in the wee hours of September 3 and Saturn spent most of the year with its rings nearly edge on.
It was a decade full of astronomical events that awed and amazed everyone that observed them. There are a few that will be remembered by many forever, such as the Great Mars Opposition of 2003, and there are other events that will be forgotten, only to be remembered again by reading articles like this. The astronomical hits of the past ten years will give way to the new decade ahead, filled with the promise of anticipated and unexpected events that define the joy of observing the heavens.