My boyfriend and I saw something weird last night from our home in suburban Franklin MA area - about 25 miles or so southwest of Boston. He brought my attention to it. It was after sunset and quite dark, maybe around 6:00 pm or so. He was getting ready to go somewhere and said there was a strange object in the sky with blinking lights going over the house. He told me to go to the back door and see it (as it should have been over the house by then). I think that would make the direction it was flying approximately southeast to northwest (I'm terrible with directions though). It was flying fairly low, at about commercial aircraft altitude (low enough to eventually pass out of sight behind the trees).
It was moving slowly, it looked like it was moving much slower than a regular plane, and it made no noise. I didn't see any other planes in the sky right at that point. It had 3 white lights (presumably on the backside that we were looking at as it flew away from us), in a straight horizontal line, and they were flashing on and off in a regular interval of every few seconds until the object itself disappeared from view. There were no other lights, like the red and green lights on a regular plane. I took a video of it on my crappy cell phone, but it was at quite a distance from us by that point and all you see is the row of white lights blinking in the distance, so I don't know if it's useful. The whole thing lasted less than 10 minutes from the time he sighted it.
Now it might just be a regular plane or some other known aircraft, but I haven't seen something like that before and neither has my boyfriend, and it just seemed odd. That's the only emotion either of us had, was that it seemed odd, with the flashing white lights. I'm wondering if you know that it's a regular aircraft of some type, or if not, you've seen other reports like this. I've seen planes with the blinking red lights, of course, but not with 3 white lights in a straight line, and I'm wondering what kind of plane or aircraft would have that physical configuration? So I'm not assuming it's some weird, unknown thing, just unknown to us. Maybe someone has some familiarity with this? We've never seen that before and we look at the skies out here quite a bit (we have a pretty clear view of much of the sky when the weather cooperates).