Hi Tom, Just as follow up, what do you think of the value of the Messenger mission, and can we ever see Merucry with the naked eye in the sky? Thanks, Bev
Hi Bev, Last question first...Yes, Mercury is sometimes visible to the naked eye, but you have to work at it. It's only easily visible to the naked-eye as a fairly bright starlike object but only twice per year; once in the western spring evening sky for about a 10 day period, and once in the fall early morning eastern sky for about 10 days also. (Assuming you live in the Northern Hemisphere, BTW). Being so close to the sun, most other times it's too close to the horizon as the sun rises or sets. Spring is already past, so if you write me sometime in Jan or Feb. I will supply you with next years best apparitions in the springtime evening sky...This fall, Mercury will be visible in the crack of dawn sky rising around 5:30 am Daylight time from October 1st thru the 11th. Make sure you have a clear, unobstructed eastern dawn horizon. On the morning of October 8th Mercury will be particularly easy as the brighter planet Saturn will be only 1/2 degree (a dime atarm's length) to the upper left of Mercury. Don't confuse these two planets with brilliant Venus which rises 30 minutes before the crack of dawn (and therefore higher in the sky than the other two planets). Around 6 am daylight time, with the sun still 12 degrees below the eastern horizon, Venus will be 10 degrees high in the east, and the Mercury/Saturn duo 5 degrees high, almost right under Venus, due east at that time. (5 degrees is about one closed fist span, at arm's length).
As far as the value of the Messenger mission to Mercury, I prefer not to comment or give an opinion....I recently got burned (rating-wise) on a 'matter of opinion' question from one of those crazy/nutty/UFO picture questioners where I disagreed with his assessment, so I prefer to let history be the final judge of a mission's value. Hope you understand, but at least I covered half of your question. Clear Skies, Tom Whiting Erie, PA