With the second-to last space shuttle mission winding down in the next few days skywatchers get their last chance ever to see Endeavour fly in the skies above, before it’s retired. The shuttle is scheduled to undock from the International Space Station late this Sunday night (May 29), and so the two spacecrafts will slowly separate in the following hours and days, making both dramatically visible as two individual, gliding stars chasing each other above backyards across much of North America and Europe.
Best times to watch will be in the early morning hours – around 4:45 am (local time) on Monday and 3:35 am (local time) Tuesday before the shuttle returns to Earth on June 1. You should be able to tell the two giant spacecrafts apart when looking up, with the space station trailing behind the shuttle, and appearing as the brighter of the two – due to its larger size and highly reflective solar panels. But not to worry, both should be so brilliant that as long as you have clear skies, they will be easily visible even from within light polluted city limits. Satellites sort of look like high flying planes without the flashing lights, moving at a brisk pace across the fixed starry background.
Taking only 90 minutes to make one orbit around Earth, expect them to cross your local sky in only 2 to 4 minutes. So to know exactly when and where you need to look for this early bird show go to the satellite tracking website heavens-above.com and enter your city and town to get a custom viewing time table. That way you know exactly when to set your alarm clock and watch history in the making .
Also visible but with much fainter flybys above North American and European skies is the first solar sail to orbit Earth. NASA’s NanoSail-D is a 100 square foot, flat, polymer sail that was placed into low Earth orbit in December 2010. Nearing the end of its experimental mission, the solar sail is in a slow tumble as it enters the Earth’s atmosphere, creating moments of bright flashes as the sun reflects off its shiny, but one dimensional surface.
Eagle-eyed skywatchers who want to take up the challenge and spot this unique artificial satellite for themselves before it burns up in Earth’s atmosphere can get viewing times on spaceweather.com’s satellite trackers webpage.
As an added viewing bonus in the last three mornings of May witness some of Earth’s neighboring worlds align, as the thin crescent moon pays a visit to planets huddling above the eastern horizon. The sky show begins about half hour before local dawn on Sunday, May 29 when the Moon first parks itself to the upper left of bright star-like Jupiter. The sparkly pair will be separated by no more than 4 degrees – only 8 full moon disks apart.
For Memorial Day morning the moon will slide lower in the sky only to be sandwiched between Jupiter above and Mars and Venus below.
By Tuesday, May 31, the waning crescent moon will have sunk much closer to the horizon, snuggling up to within 5 degrees of white beacon-like Venus. As an added observing challenge try and hunt down faint Mercury by using binoculars to scan just below the moon. What a cosmic way to end the month!
Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.