Attention Space Cadets! The International Space Station has been a regular visitor lately for those hardy souls who are up and outside before dawn breaks. For the rest of us, the ISS is returning this weekend to the more user-friendly evening sky.
Friday marks the beginning of a fine series of flyovers by the growing, and increasingly brilliant manned space laboratory. If you have never seen it go by, or have not rousted the kids out from behind their computer games to see it, make a resolution to do so this weekend. The weather looks promising. And who knows? The spectacle might inspire the videoheads to crack the science books and become astronomers, or astronauts, or (if things go badly) newspaper science writers.
The ISS, traveling at an orbital velocity of about 17,500 mph, circles the planet once every 90 minutes, so there are more opportunities to see it than I will note here. I'll spare you the passes that are very close to the horizon, and liable to be lost in the clutter of trees, rooftops and urban air pollution. I also skip those that are rather short - when the station rises above the horizon, for example, and quickly plunges into the Earth's shadow, and disappears from sight.
Here then, are the brightest and best four opportunities for the coming weekend. If skies are clear, or mostly so, just step outside at the stated times, look in the right direction, and you will see the station. For the uninitiated, it will rise above the horizon looking like a steady white star, except it will be moving higher into the sky at a brisk clip. It's traveling at about 17,500 miles per hour, and will usually cross the entire sky in just 4 or 5 minutes.
If you see something moving with multiple lights, or flashing lights or colored lights, it's an airplane. Keep looking. What you're seeing of the station is actually sunlight, reflected off the ISS's reflective solar panels, or shiny metal shell. And as the ISS has become larger during the construction of the last few years, the more sunlight it's been reflecting. It is bright enough now to shine through hazy skies and thin clouds. And it can be seen even before the sky is totally dark. Some satellite enthusiasts have spotted it in the daytime.
There is a crew of three on board. Here's more on them and what they're up to.
If you want to see more of the station, you can get flyby predictions online from Heavens-Above.com Just sign in, punch in your location, and it will provide all sorts of information, from ISS flybys to maps of the night sky. Try it. Those are your tax dollars up there.
So, without further ado, here are the specifics for the best ISS passes for the Baltimore area from Friday through Monday evenings:
FRIDAY: The ISS will appear above the southwestern horizon at 7:59 p.m. as it soars up the East Coast from Florida to the Outer Banks, it will appear from Baltimore to fly just above and very close to the bright planet Jupiter in the southern sky. It will be not quite halfway up the southeastern sky at 8:01 p.m., moving just below the bright star Altair, the southernmost member of the Summer Triangle. From there, the station will move off toward the eastern horizon, disappearing into Earth's shadow at 8:03 p.m.
SATURDAY: This time, the ISS will be flying a parallel track to Friday's, but farther to the west, flying up the Appalachian mountain chain toward New England. From here, it will appear above the southwestern horizon at 8:25 p.m., climbing to about 50 degrees above the northwest horizon - more than halfway up the sky and well above the Big Dipper, if you can see that constellation. From there it will zip off toward the northeast, vanishing near the "W"-shaped constellation Cassiopeia at 8:29 p.m.
SUNDAY: This pass will be almost identical to Friday's, except the times will change, and it will be slightly higher in the sky. Look for the station to rise above the southwestern horizon at 7:16 p.m., flying above the planet Jupiter - the brightest object in the southern sky. It will pass just beneath Altair again, then head off toward the northeast, disappearing close to the horizon around 7:24 p.m.
MONDAY: This will be a pass much like Saturday's, as the station once again flys up the Appalachian chain toward the Canadian maritime provinces. Look for it above the western horizon at 7:43 p.m., rising to about halfway above the northwestern horizon by 7:45 p.m. Then it will fly off toward the northeast, disappearing at 7:49 p.m.
If you're really into this stuff, there will be opportunities this weekend to spot the much smaller and fainter, 22-ton European spacecraft Jules Verne. It recently left the ISS and is headed for a fiery re-entry later this month. Here are the specs on Jules Verne's passes over Baltimore, along with the ISS.
Good luck. Be sure to come back here after the show and leave a comment. Share the experience.