On July 1st – The Battle of Gettysburg Began, Lexell’s Comet passes close, and Juno nears Jupiter!
As I reviewed the events that occurred on July 1st throughout history this morning, the first event that came to mind was the start of the Battle of Gettysburg on July 1, 1863…. From Wikipedia….
The Battle of Gettysburg] was fought July 1–3, 1863, in and around the town of Gettysburg, Pennsylvania, by Union and Confederate forces during the American Civil War. The battle involved the largest number of casualties of the entire war and is often described as the war’s turning point. Union Maj. Gen. George Meade‘s Army of the Potomac defeated attacks by Confederate Gen. Robert E. Lee‘s Army of Northern Virginia, ending Lee’s attempt to invade the North.
After his success at Chancellorsville in Virginia in May 1863, Lee led his army through the Shenandoah Valley to begin his second invasion of the North—the Gettysburg Campaign. With his army in high spirits, Lee intended to shift the focus of the summer campaign from war-ravaged northern Virginia and hoped to influence Northern politicians to give up their prosecution of the war by penetrating as far as Harrisburg, Pennsylvania, or even Philadelphia. Prodded by President Abraham Lincoln, Maj. Gen. Joseph Hooker moved his army in pursuit, but was relieved of command just three days before the battle and replaced by Meade. Continue Reading
Certainly a terrible three days in our nation’s history. Looking on I saw an interesting astronomical event that took place way back in 1770….
Lexell’s Comet Passes Closer than any other Comet in Recorded History – July 1, 1770
D/1770 L1, popularly known as Lexell’s Comet after its orbit computer Anders Johan Lexell, was a comet discovered by astronomer Charles Messier in June 1770.[note 1] It is notable for having passed closer to Earth than any other comet in recorded history, approaching to a
distance of only 0.015 astronomical units (2,200,000 km; 1,400,000 mi). The comet has not been seen since 1770 and is considered a lost comet…..
…..The comet was discovered on June 14, 1770, in the constellation Sagittarius by Messier, who had just completed an observation on Jupiter and was examining several nebulae….
……On July 1, 1770, the comet passed 0.015 astronomical units from Earth, or approximately 6 times the radius of the Moon’s orbit. Charles Messier measured the coma as 2° 23′ across, around four times the apparent angular size of the Moon. An English astronomer at the time noted the comet crossing over 42° of sky in 24 hours; he described the nucleus as being as large as Jupiter, “surrounded with a coma of silver light, the brightest part of which was as large as the moon’s orb”.
Early astronomical discoveries like this amaze me! They were all done without any fancy astronomical equipment. This is not the first time I have written about Charles Messier an amazing astronomer. Here’s an earlier post.
Speaking of astronomical equipment it appears that the eyes of the astronomic world will be on Jupiter this July 4th, when it completes its five-year world to the giant planet. From The Boston Globe……
As NASA’s Juno spacecraft closes in for its July 4 arrival at Jupiter, many other eyes are also staring at the solar system’s largest planet.
Data from about 25 observatories, including some of the largest on Earth, like the W.M. Keck Observatory in Hawaii, and in orbit around Earth like the Hubble Space Telescope, will aid scientists in interpreting the data that Juno is expected to gather as it swoops close to the cloud tops of Jupiter over the next 20 months.
It has taken Juno nearly five years to reach this point in its journey.
“In just a few days, we’re about to arrive at Jupiter, and it’s hard to believe,” Scott Bolton, the mission’s principal investigator, said at a NASA news conference on Thursday….. Read More
So doing a little time jumping we have traveled from Gettysburg in 1863, back to 1770 and Charles Messier’s discovery of Lexell’s Comet and then forward to the future exploration of Jupiter starting in a few days! Beat Mr. Messier would be eager to see what they discover!
A busy July 1st! Have a great holiday weekend!!