by Randy Muller
I had a wonderful view of the Venus and Jupiter conjunction Tuesday night, February 23, between 6:15 and 6:45pm. I felt very lucky, because the sky was covered with clouds the day before, the day after and even during the day.
I dragged a friend of mine at work outside and we attempted to view the conjunction by naked eye at about 2pm, but there was a thin layer of cirrus clouds scattering the sun's light, making it impossible to see the planets.
After work, I rushed home through rush-hour traffic that was not rushing as much as I wanted. I used the time to decide which scope to set up. I decided on the Big Feller, my 10" f/5.6 dob, because of the minimal setup time. I knew I was not going to have much time to watch the celestial show.
Minutes after I got home, I had the scope set up in the backyard. The show had begun. By naked eye, the view was absolutely stunning: The two brightest planets in the sky were extremely close together at medium-to-low altitude in the west. Both Saturn and the moon were also visible higher and further to the east.
Venus was much brighter, and barely above Jupiter, making it (Jupiter) look almost faint by comparison. A very casual observer might not have even noticed Jupiter because it was so close to the far brighter Venus. This was definitely the closest grouping of two planets I've ever seen, but this is unremarkable because I have not closely observed many others.
Looking through the scope, Venus showed an obvious gibbous phase, with the terminator pointing nearly straight down (in my inverted newtonian view), with Jupiter above it, approximately 30 degrees off a vertical line, on the opposite side of Venus' terminator.
The image of Venus was swimming a bit and was suffering some pretty good chromatic aberration due to the atmosphere.
I was barely able to frame Jupiter and Venus in the same field of view with my 10mm eyepiece, at 142x. This yields a rough estimate of how close the objects were: The eyepiece has a 50 degree apparent field of view, thus the planets were closer than 50/142 = .35 degree, or 21 arc minutes.
The color contrast between Jupiter and Venus was very interesting and stark: Venus was blindingly bright white -- pure white. Jupiter was much paler and tannish. The tan color was very distinct when compared to Venus. It was clearly not white or yellow or off-white. The North and South Equatorial Belts were deeper tan.
On Jupiter, I could see the N & SEBs, but no other detail. The seeing that low was pretty ratty. Callisto and Europa were on the opposite side of the planet from Venus, and Ganymede was on the Venus side of Jupiter.
The moon was REALLY high, so I took a peak and it was just fabulous! There were rilles and crater chains and humps and bumps and pits and rocks all over the place.
I also looked at the Orion Nebula, and could easily see 6 stars in the Trapezium, so the seeing was actually pretty good.
After Jupiter and Venus got low, I left my scope outside cooling off to view the moon later. Of course, later the whole sky was covered with clouds, so I felt really lucky that it was clear for the conjunction at precisely the right time for me to see it.
| Date | February 23, 1999 6:15-6:45pm (0215-0245 Feb 24 UTC) |
|---|---|
| Location | Backyard, in Roseville, CA 121W 16', 38N 44' |
| Instrument | Orion DSE 10" f/5.6 dob-newt |
| Oculars | 10mm, 26mm plossls |
| Seeing | 8/10 very steady, scope not in equilibrium |