The sky this summer has two visitors from the asteroid belt that are getting with close range to each other visually to an observer from the surface of Earth. Recently both were promoted to be called dwarf planets by the text books.
For most of the year, (from observations and public open source data on the web) the two asteroids will be within few angular degrees from each other, and just recently, there at their closest point in July 4th/5th.
At the night of July-9th-2014, both asteroids were in the Virgo constellation area in the sky. Around 10 pm, the asteroids looked above the planet Mars and the star Spica (Mars and Spica were two degrees and a quarter apart from each other). As shown in the pictures taken this night, Ceres and Vesta were trapped between the stars Spica and Zeta Virgo.
Ceres is the one in the left, and Vesta is on its right side. Vesta looked brighter with magnitude of 6.38~6.7 than Ceres which had a magnitude of 7.69~8. (Again, the smaller the magnitude number, the bright the object is). Ceres roughly is twice the size of Vesta, however, due to asteroids locations from the Sun, and from Earth, it worked out for Vesta to be brighter in this time of their orbits.
The distance of Vesta that night was 1.818 AU, and Ceres to be 2.38 AU from Earth.
AU = Astronomical Unit = the average distance of earth from the Sun = 150 million Kilometers (93 million miles).
The visual separation of the asteroids was nearly 18 arcmin and a half. (Roughly, 2 thirds the appearing size of the Moon from earth surface).
The location in which the observations were taken was at South Fork trail in Santa Clarita, near the old bridge (Pictures included of the bridge) which had less light pollution than down town Los Angeles.
July – 9th -2014
Santa Clarita, California.