Vermin of the sky strike again
WALTER Baade was a giant of 20thcentury astronomy. He is celebrated for accurately calculating the distance to the Andromeda galaxy by carefully studying variations of a particular class of star called Cepheids. During his distinguished career, Baade also discovered several asteroids. He wasn’t a fan, referring to them as ‘‘vermin of the sky’’ because their trails spoiled photographs of galaxies he was studying.
Baade’s phrase came to mind one morning last week. I was standing beside Papanui Inlet, hoping to get pictures of comet Swan. Having set up my telescope and located the comet I began a sequence of photographs. I relaxed and savoured the magnificent Milky Way high overhead. Unfortunately, soon after 6am, my cosmic ruminations were rudely interrupted by the passage of 60 bright satellites in a line which took nearly five minutes to cross the sky. I had been Starlinked.
Over the past few months, the American company SpaceX has been launching batches of Starlinks. Their aim is to create a megaconstellation comprising some 12,000 satellites whose purpose is to provide ‘‘lowcost’’ worldwide internet access. To put it in context, since the dawn of the space age, approximately 9000 satellites have been sent into orbit.
Soon after launch, Starlink satellites are visible as very bright ‘‘trains’’, which have given rise to many reports of UFOs. Starlink has also raised the ire of astronomers. This is because the passage of a satellite through an image can mean essential data may be lost. The satellites slowly spread out and get dimmer as they raise their orbits, but from dark sky sites they can still be seen with the unaided eye. SpaceX is supposedly trying to address the impact their satellites have on astronomy. However, after seven launches, the 420 satellites at present in orbit are becoming annoyingly familiar sights during this stargazer’s observing sessions.
Some have argued that the proliferation of satellites is progress, and their impact on the night is a small price to pay for highspeed global internet. I beg to differ and find myself wondering what Baade would think about the latest generation of celestial vermin.