Starlink Satellites May Change The Night Sky As We Know It


SpaceX Starlink satellite “train” passing over San Diego on Nov. 12, 2019. You can’t deny how many amazing they look, but will the satellites prove too much of a good thing? Click here for another recent video.

Prepare for the industrialization of space. On Nov. 11, SpaceX launched a Falcon 9 rocket loaded with 60 new Starlink satellites, part of an ambitious effort by the organization’s founder, Elon Musk, to provide worldwide internet access via satellite. Tuesday’s liftoff was the second following the inaugural launch in May.

Musk’s initial plan was to create a “constellation” of 12,000 satellites, each the size of a kitchen table, in three orbital shells at altitudes of 217 miles, 342 miles and 715 miles (350 km, 550 km and 1,150 km). That number gave many of us pause because of concerns about changing the appearance of the night sky.

In this artist concept, Starlink satellites unfurl their solar arrays. Electricity from the cells powers a krypton ion propulsion system so that each satellite can move to a designated spot in the constellation. SpaceX

Consider this. There are just under 10,000 stars visible with the naked eye across the entire planet on the darkest nights, which would mean more Starlinks than stars! Professional astronomers as well voiced concerns about the effects of so many moving lights on photos and measurements taken by telescopes at observatories across the world. I think most of us would say that satellites are fun to watch. But if they’re crawling the skies during much of the night as this constellation is expected to do, our joy may dwindle.

If 12,000 artificial stars isn’t bad enough from a skywatcher’s perspective, hold your breath. That might be just the first wave. SpaceX filed paperwork with the International Telecommunication Union recently for an additional 30,000 satellites to operate in low Earth orbit between 204 and 360 miles (328-580 km) altitude. Talks are also underway with the U.S. Air Force to provide internet access plane communications.

I tried to capture the first Starlink train last May in this 1-second exposure at ISO 32,000 — the fastest I could make but still not enough to stop motion so you can see the many individual satellites. Bob King

To address concerns, Musk agreed to paint the undersides of the satellites black. But given that the solar arrays are the brightest part of each Starlink it’s doubtful the move will alleviate the problem. There are currently 18,400 large, artificial objects in orbit including rocket boosters and debris, a number that could nearly triple in just a few years in large part due to a single company.

We tend to think of the sky above as local, but it’s shared by every human on the planet. When satellites are launched into orbit from the U.S. (or anywhere else for that matter) they also track across African, South American and  European skies. Nor is SpaceX the only company interested in space-based services. Amazon’s Kuiper Systems and OneWeb are expected to send up constellations of their own.

So how bright are these things and will we really notice? From city and bright suburban locations there are easily visible within a few days of launch. But as their orbits are raised after their operation is checked they become fainter because they’re farther away. During the most recent launch observers in the southern U.S. had good views for about two nights — there were few if any passes over the northern U.S.

This week they will become widely visible in the morning sky shortly before and at dawn but have since faded and spread out. Most are now as bright as the fainter stars or around magnitude 5. To see the majority you’ll need to use a pair of binoculars from suburban and rural locations. As for the original 60 that are now in place in orbit, their brightness ranges from about magnitude 4 (visible without binoculars from a reasonably dark sky) to dimmer than 8. In other words, they’re still relatively bright, a bad sign that they could become a nuisance to amateur and professional astronomers. Especially as more volleys are lofted into orbit.

I understand the desire for better internet access especially in areas where there is no service, but as a sky lover I’m concerned about how my favorite wilderness will be compromised. Not just for me but for everyone.

How to See the Starlink satellites

The easiest way is to go to Heavens Above and click the Login link under Configuration. Once you create a free account, select your city and then return to the main page and click the Starlink — all objects from second launch link. You’ll next see a list of all the new objects in orbit. Information in the table includes brightness — magnitudes 1 and 2 are bright and easy to see; magnitude 4.5 and lower will require binoculars — along with peak altitude and direction in which to look.

Heaven’s Above home page with key links outlined. Courtesy of Heavens Above / Chris Peat

While helpful, you really need a map to know exactly where to look. To get one, click the time link and a map pops up showing the satellites path across the sky. From many locations, the Starlinks will track low across the southern sky for some of the passes and higher up in the southern or northern sky during more favorable ones. Remember to go outside about 15 minutes before a pass to allow time for your eyes to dark-adapt and to make sure there are no trees or buildings blocking the view of the path.

Clicking on the Starlink link brings you to a list of passes of each Starlink satellite with times and altitudes. When you click the highlighted time link you’ll get a map of its path. This list is for Minneapolis, Minn. Courtesy of Heavens Above / Chris Peat

The satellites are getting fainter and more spread out with time, so try to see them now.  Many of the Starlinks require binoculars to see. I try to pick a bright star near the path and offset from it to where I expect to see the satellite. I point the binoculars there and wait for the satellite to zip across the field of view. The brilliant star Arcturus will be a good choice from some locations.

After you click on the time link you’ll get a chart with the satellite’s path for a particular day and time. Courtesy of Heavens Above / Chris Peat

Since all the satellites follow nearly the same path, once you’ve spotted the first one you can just wait for the rest to follow, one after another. For instance, in Duluth on Nov. 23, the first Starlink appears very low in the southeastern sky at 5:47 a.m. followed by the last at 6:36 a.m., a spread of more than 45 minutes! They range in brightness from magnitude 5 to 2.7 and pass below the tail of Leo the lion and very near Arcturus.

If you don’t see them this time around you won’t have to wait long for the next batch. SpaceX plans monthly launches of 60 satellites at a pop every month of 2020. The best time to catch them is within the first couple nights of launch when they’re still bunched up in a line.