Get ready planet Earth – there’s no escaping celebrity. Not only will NASA’s Cassini spacecraft be taking your picture tomorrow but so will the Mercury MESSENGER probe at the other end of the solar system.
Last month I described NASA’s plan to snap a picture of Earth from Saturn using the Cassini spacecraft, which has orbited the ringed planet since 2004. That happens tomorrow July 19 over a 15-minute span beginning at 4:27 p.m. (Central Daylight Time) and ending at 4:42 p.m.
Inspired in part by the Cassini team’s plans, scientists reexamined planned observations of NASA’s MESSENGER spacecraft in orbit around Mercury and realized that Earth would coincidentally be in some of the images during a planned search for possible Mercury moons on July 19-20.
Also coincidentally, MESSENGER will see the side of Earth that Cassini does not and more. Taken together, the two spacecraft will picture most of humanity compressed down to a pixel or two. This is an important point — literally. Earth is too far from both probes to appear as anything more than a tiny dot.
If you live in North America, Central America and the northern part of South America, Saturn will appear in the daylight sky. NASA encourages you to look to the southeast at the time and wave at the planet. You might even consider going that extra mile and shouting out “cheese!”
While it will be daylight in much of the western hemisphere at the time of the photo shoot, European and African observers will see Saturn glowing in the southwestern sky when the shutter winks open and close. Meanwhile, MESSENGER will snap its portraits of Earth at 6:49 a.m., 7:38 a.m. and 8:41 a.m. CDT on both days. Mercury will be about one fist held at arm’s length to the right (west) of the sun at the time and invisible in its glare.
“Nearly half of the Earth, including all the Americas, Africa, and Europe and Central Asia will be illuminated and facing MESSENGER, says Hari Nair, the Johns Hopkins University Applied Physics Laboratory planetary scientist who designed and is implementing the campaign,” according to a press release on the MESSENGER website.
The images on the second day will also include pictures of the Moon as will the Cassini photos. Details about the Saturn campaign including maps for various cities to help you find the planet can be found HERE. More information on the event’s Facebook page.
While the photos won’t reveal any details on the planet, seeing Earth as a point of light will refresh our day with a cosmic perspective on life.