Asteroid 433 Eros, Part 3

The late 1800s and early 1900s was an era of immense astronomical focus on 433 Eros. During this time at Harvard College Observatory, a series of documents called Circulars were disseminated as a way to publish discoveries and other important findings by the observatory. One thing to note when reading early papers on Eros is that it is often referred to as a planet. The designation of an asteroid was created by William Herschel in 1802, almost 100 years before these papers.[1] Despite this, it was common for asteroids to be referred to as planets for decades after this designation was formalized,[2] so it not likely that Eros was believed to be a new planet at the time.

This era was also a time when the “Women Computers” carried out a large portion of the data analysis at the HCO. Williamina Fleming was one of the scientist at Harvard College Observatory who worked with plates of Eros. Williamina Fleming was originally the housekeeper of Edward Pickering, the director of the Harvard College Observatory. As the legend goes, Pickering, who became frustrated with the men who worked at the observatory, stated that his housekeeper could do a better job. Fleming, his housekeeper, then became one of the famous “Women Computers” of the observatory.[3] Other women who worked on Eros include Evelyn Leland, Ida Woods, and Anna Winlock.[4] Reduction of Eros data is one of the many ways the women at Harvard College Observatory contributed to the astronomical studies of the time.

In more modern times, Eros has been a part of other groundbreaking studies. NASA’s NEAR Shoemaker mission was the first probe to land on an asteroid in 2000. That asteroid was 433 Eros. While operational, NEAR Shoemaker analyzed mass distribution and gravity fields around the asteroid, took the first close-up, high-resolution images of an asteroid, and detected gamma-ray bursts.[5]

Eros, over the past 120 years, has been a central area of numerous astronomical studies, even beyond those explored in these posts. The HCO’s role to these projects has been invaluable. Eros will forever hold a special place in scientific history.


The above image, courtesy of NASA, was taken by the NEAR mission 83 kilometers above the surface of Eros.[6]

[1] “William Herschel And The First Two Asteroids.” The SAO/NASA Astrophysics Data System, n.d. Web. 12 Aug. 2013. .…11….3C
[2] Hilton, James. “When Did the Asteroids Become Minor Planets?” Naval Oceanography Portal, n.d. Web. 13 Aug. 2013.
[3] “Williamina Fleming.” Williamina Fleming. N.p., 2013. Web. 20 Aug. 2013.
[4] Pickering, Edward Charles. “Early Observations of Eros (433).” The SAO/NASA Astrophysics Data System, 1905. Web. 28 July 2013.
[5] “NEAR Shoemaker.” NASA, n.d. Web. 3 Sept. 2013.
[6] Williams, David R., Dr. “NEAR Orbit Around Asteroid 433 Eros.” NEAR Eros Images. NASA, 2001. Web. 26 Sept. 2013.
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