And yes the twain shall meet! Tonight I have a couple new photos to share with you showing the asteroids Ceres and Vesta just before their face-to-face meeting on July 5. That night they’ll be 10 arc minutes or just a third of a full moon diameter apart. Don’t fret if the weather’s supposed to be cloudy then – they’ll be nearly close tonight through the 6th.
Besides, tonight the moon’s still a crescent and neither as bright nor as close to our asteroidal celebrities as it will be on the 5th. Glare that night will make seeing fainter Ceres difficult. If you have a telescope, both can be viewed right on through the full moon.
Vesta shines at magnitude 7, one magnitude fainter than the naked eye limit. I had no problem seeing either asteroid in 8×40 binoculars last night (July 2). They also showed up in my camera with a 15-second exposure at ISO 2500 with the lens wide open at f/2.8. The next few nights present a great opportunity for anyone with a medium to higher end digital camera and tripod to create a series of photos showing their convergence and divergence over time. A animated gif of the motion would be sweet!
Italian astronomer Gianluca Masi plans to feature live telescope images of Ceres and Vesta at closest approach on his Virtual Telescope site beginning at 3 p.m. CDT (4 p.m. EDT, 2 p.m. MDT and 1 p.m. PDT) Saturday July 5.
Hope you get to see the pair. Their last conjunction was in 1996 when they were much farther apart (2 degrees). And don’t forget the nearby conjunction of the moon and Mars with Spica nearby the same night.