Today the planet Mercury passed across the Sun from the perspective of us Earthlings. Our orbit and that of Mercury have to align just so for this to occur. The last Mercury transit was in 2016; the next will be in 2032.
To observe a transit you need to protect your eyes with a proper solar filter. Once equipped, you can see Mercury in silhouette – a small black disk – moving across the Sun. The motion is fast enough that you can track Mercury’s progress by eye over the course of several minutes. The entire transit from first to last contact lasts about 5 1/2 hours.
I set up my telescope (with a solar filter) at my corner and invited passersby to look. Before long I had quite a crowd – I should do solar astronomy more often!
Location: 181 St., Washington Heights