I sometimes post stuff here
There's a story that goes something like this: In 1925, lightbulb manufactures secretly colluded to standardized lifespans at 1,000 hours. They would test each other's products to ensure compliance. This is true. At the time, many bulbs lasted longer than one thousand hours. This is true. Therefore, this must have been done so that people would always need to buy more light bulbs. This isn't quite…
One of the cool features of JPEG files is that there's the option to save low frequency components first. This means that a partially downloaded image will be displayed at low resolution instead of being cut off. In the file, this works by breaking up the compressed data into multiple "scans", each prefixed with a header. Here's the first scan of a representive image: FF DA - "start of scan"…
North is up (aprox). 0.53 "/pixel. [24' x 23' field] FWHM = 3.75" A relatively unremarkable spiral galaxy... but hey, what's that in the background? Click to toggle annotations. (needs JS) Well, it's not actually in the background: the nebula is closer than the galaxy. This particular reflection nebulously is unusual because it's quite far from the milky way, and it doesn't have a central star.…
Summer gets really hot, and it's not going to get better anytime soon. At my place, it isn't actively dangerous yet , but it's still unpleasant. A normal air conditioner uses a low boiling-point liquid: something like liquid propane can boil down to -42 C. Just like water, it's evaporation absorbs a lot of heat and the remaining liquid will become very cold. Of course, releasing the gas would be…
North is up (exact, mirrored). 0.53 "/pixel [18.8' x 7.4'] FWHM = 4.2" This galaxy has a massive (and rather bright) tidal tail, but I can't see an obvious companion galaxy. The general consensus is that there's a second galaxy behind it... although a nearby elliptical has a suspiciously similar redshift: Total exposure time: 364 * 30 seconds = 3 hours. Used in stack: 165 * 30 seconds = 1.3 hours.…