On Friday night – June 20th – I went to the club’s observatory to meet with Michel Renaud and observe some asteroids. After 10 pm, when the last visitors departed, we prepared for our observations. Our initial plan was to observe Near Earth Asteroid 2014 KS40 , which was discovered last month, on May 25th 2014. But since there were many clouds at the direction of the asteroid (a very dificult target, mag 17) we decided to look for something easier. At Starry Night we found Main Belt asteroid 45-Eugenia, which was conveniently placed well above the Ecliptic, at about 35 degrees South, in constellation Libra, free of clouds!
We the help of Starry Night software and the Minor Planet Center Ephemeris Service http://www.minorplanetcenter.net/iau/MPEph/MPEph.html for exact coordinates, we started our step by step star hopping, with the finder scope and a Celestron 35 mm eyepiece. The order of the pre-pont target stas was: Zubeneschamali (β Librae, 2.5 mag), the optical double star HIP 75718 – HIP 75722 (5.5 & 6.0 mag), HIP 75763 (7.7 mag), TYC 5595-492 (9.3 mag), HIP 76086 (9.1 mag) and finally the equilateral triangle of three 2UCAC catalog stars: 28742673 (12.6 mag), 28742663 (12.85 mag) and 28742667 (13.17 mag). All stars were easily seen and identified by both of us. The position of 45-Eugenia was expected to be symmetrical to 2UCAC 28742673, so that a new rhombus (diamond) shape is formed by extending the triangle. You can see the star field and these geometrical shapes in the following star chart produced with the Simbad Astronomical Database & Aladin Sky Atlas.
The asteroid was there! At the position of the purple cross no star is expected, but a 11.3 mag light source was there: Eugenia!!!
The time was now after midnight, June 21st and we were technically in the day of the Summer Solstice! Before we go Michel decided to take captures of the asteroid, so we stayed half an hour more, in order to get two shots with difference in time, so that we could identify the asteroid by its motion. Michel placed his camera on the eyepiece holder of the telescope and took a 10 second exposure. As we were waiting for the 2nd exposure, we had a great time talking about astronomy and music!
Next morning I worked with Michel’s jpg captures. I used the MaximDL software to align them, Adobe Photoshop to enhance contrast and reduce brightness a bit, and Image Ready to produce a GIF image to animate the asteroid’s motion. Here it is! Michel, thank you for the wonderful night at the observatory!
Click on image to see the asteroid motion
For the history, asteroid Eugenia was discovered in Paris on June 27th 1857 by German-French astronomer Herman Goldschmidt.