Collaborate Disseminate
Astronomers have discovered the most distant – and therefore earliest – known black hole. Hiding in a galaxy called GN-z11, this black hole is bigger than should be possible given the age of the universe.Continue ReadingCategory: Space, ScienceTags: Bl… Continue reading Most distant black hole discovered, but it’s “impossibly massive”
Without any sort of restrictions on designs for trebuchets, these medieval siege weapons are known to send 90 kilogram projectiles over 300 meters. The egg-launching trebuchet contest that [AndysMachines] is …read more Continue reading Trebuchet Sends Eggs Flying
For the first time in more than 30 years, new terms have been officially added to the International System of Units (SI). The four new prefixes – ronna, quetta, ronto and quecto – describe very large and very small numbers that until now didn’t have th… Continue reading Quettabytes and ronnagrams: Extreme numbers get new official names
It’s fascinating to see what happens when a creative hacker is given a set of constraints to work within. [rctestflight] found themselves in a very specific set of circumstances: Free …read more Continue reading RC Car Test Tether Takes Car Testing To New Lengths
Those with small garages might be familiar with the method of hanging a tennis ball from a ceiling to make sure they don’t hit the back wall with their car. If the car isn’t in the garage, though, the tennis ball dangling from a string tends to get in the way. To alleviate this problem, [asaucet] created a distance sensor that can tell him when his car is the perfect distance from the garage wall.
At the heart of the distance sensor is an HC-SR04 ultrasonic rangefinder and a PIC16F88 microcontroller. [asaucet] uses a set of four LEDs to alert …read more
Continue reading Garage Distance Sensor Kicks Tennis Ball To Curb
Pour yourself a nice hot cup of tea, because [iliasam]’s latest work on a laser rangefinder (in Russian, translated here) is a long and interesting read. The shorter version is that he got his hands on a broken laser security scanner, nearly completely reverse-engineered it, got it working again, put it on a Roomba that was able to map out his apartment, and then re-designed it to become a tripod-mounted, full-room 3D scanner. Wow.
The scanner in question has a spinning mirror and a laser time-of-flight ranger, and is designed to shut down machinery when people enter a “no-go” region. …read more
