In times like these, we all need to look beyond ourselves. This project might help: OnStep is an open-source telescope controller, a device that controls a telescope to point at something interesting in the sky. Want to take a look at M31? Use an app on a PC or smartphone, select the object and the OnStep will pan and tilt your telescope until the Andromeda Galaxy pops into view.
The South Florida Science Center recently added a new ten-inch telescope and turned to [Andres Paris] and his brother to replace the hand-cranked dome door system. They turned to an Arduino along with some beefy motor drivers. You can see some videos of the beast in operation, below.
According to a Reddit post, the brothers picked up a 5A 12V motor but decided to overdesign and selected an H-bridge that would handle 20A peak current. An IR remote allows the operator to open and shut the door and reed switches sense the extremes of the door’s motion.
Join us on Wednesday, January 15 at noon Pacific for the Habitable Exoplanets Hack Chat with Alberto Caballero!
Many of the major scientific achievements of the last 100 years or so have boiled down to problems of picking out a signal from the noise. Think about analyzing the human genome, for instance: we each have something like two meters of DNA coiled up inside each cell in our body, and yet teasing out the information in a single gene had to wait until we developed sufficiently sophisticated methods like PCR and CRISPR.
Similarly, albeit on the other end of the scale, the search for planets beyond our solar system wasn’t practical until methods and instruments that could measure the infinitesimal affect a planet’s orbit on its star were developed. Once that door was unlocked, reports of exoplanets came flooding in, and Earth went from being a unique place in the galaxy to just one of many, many places life could possibly have gotten a foothold. And now, the barrier for entry to the club of planet hunters has dropped low enough that amateur astronomers are getting in on the action.
Alberto Caballero is one such stargazer, and he has turned his passion for astronomy into an organized project that is taking a good, hard look at some of our nearest stellar neighbors in the hope of finding exoplanets in the habitable zone. The Habitable Exoplanet Hunting Project is training the instruments in 33 observatories around the globe on ten stars within 100 light-years, hoping to detect the faint signal that indicates an orbiting planet. They hope to add to the list of places worthy of exploration, both from Earth via optical and radio telescopes, and perhaps, someday, in person.
Continue reading “Habitable Exoplanets Hack Chat”
Spotting satellites from the ground is a popular pastime among amateur astronomers. Typically, the ISS and Iridium satellites have been common sightings, with their orbits and design causing them to appear sufficiently bright in the sky. More recently, SpaceX’s mass launches of Starlink satellites have been drawing attention for the wrong reasons.
Starlink is a project run by SpaceX to provide internet via satellite, using a variety of techniques to keep latency down and bandwidth high. There’s talk of inter-satellite laser communications, autonomous obstacle avoidance, and special designs to limit the amount of space junk created. We’ve covered the technology in a comprehensive post earlier this year.
The Starlink craft have long worried astronomers, who rely on a dark and unobstructed view of the sky to carry out their work. There are now large numbers of the satellites in relatively low orbits, and the craft have a high albedo, meaning they reflect a significant amount of the sunlight that hits them. With the craft also launching in a closely-packed train formation, there have already been impacts on research operations.
There is some hope that as the craft move to higher orbits when they enter service, this problem will be reduced. SpaceX are also reportedly considering modifications to the design to reduce albedo, helping to keep the astronomy community onside. Regardless, with plans on the table to launch anywhere from 12,000 to 42,000 satellites, it’s likely this isn’t the last we’ll hear about the issue.
By now you’ve almost certainly heard about the recent release of a high-resolution satellite image showing the aftermath of Iran’s failed attempt to launch their Safir liquid fuel rocket. The geopolitical ramifications of Iran developing this type of ballistic missile technology is certainly a newsworthy story in its own right, but in this case, there’s been far more interest in how the picture was taken. Given known variables such as the time and date of the incident and the location of the launch pad, analysts have determined it was likely taken by a classified American KH-11 satellite.
The image is certainly striking, showing a level of detail that far exceeds what’s available through any of the space observation services we as civilians have access to. Estimated to have been taken from a distance of approximately 382 km, the image appears to have a resolution of at least ten centimeters per pixel. Given that the orbit of the satellite in question dips as low as 270 km on its closest approach to the Earth’s surface, it’s likely that the maximum resolution is even higher.
Of course, there are many aspects of the KH-11 satellites that remain highly classified, especially in regards to the latest hardware revisions. But their existence and general design has been common knowledge for decades. Images taken from earlier generation KH-11 satellites were leaked or otherwise released in the 1980s and 1990s, and while the Iranian image is certainly of a higher fidelity, this is not wholly surprising given the intervening decades.
What we know far less about are the orbital surveillance assets that supersede the KH-11. The satellite that took this image, known by its designation USA 224, has been in orbit since 2011. The National Reconnaissance Office (NRO) has launched a number of newer spacecraft since then, with several more slated to be lifted into orbit between now and 2021.
So let’s take a closer look at the KH-11 series of reconnaissance satellites, and compare that to what we can piece together about the next generation or orbital espionage technology that’s already circling overhead might be capable of.
Humans first walked on the moon 50 years ago, yet there are some people who don’t think it happened. This story is not about them. It turns out there was another great conspiracy theory involving a well-known astronomer, unicorns, and humanoids with bat wings. This one came 134 years before the words “We chose to go to the moon” were uttered.
The 1835 affair — known as the Great Moon Hoax — took the form of six articles published in The Sun, a newspaper in New York City. Think of it like “War of the Worlds” but in newspaper form — reported as if true but completely made up. Although well-known astronomer John Herschel was named in the story, he wasn’t actually involved in the hoax. Richard Adams Locke was the reporter who invented the story. His main goal seemed to be to sell newspapers, but he also may have been poking fun at some of the more outlandish scientific claims of the day.
Perched atop a dormant volcano far above the roiling tropical air of the Big Island of Hawai’i sit two of the largest optical telescopes in the world. Each 10-meter main mirror is but a single part of a magnificent machine weighing in at some 400 tons that needs to be positioned with incredible precision. Keeping Keck 1 and Keck 2 in peak operating condition is the job of a team of engineers and scientists, so when the servo amplifiers running the twelve motors that move each scope started to show their age, [Andrew] bit the bullet and rebuilt the obsolete boards from scratch.
The Keck telescopes were built over three decades ago, and many of the parts, including the problematic servo amps, are no longer made. Accumulated wear and tear from constant use and repeated repairs had taken their toll on the boards, from overheated components to lifted solder pads. With only some barely legible schematics of the original amplifiers to go by, [Andrew] reverse engineered new amps. Some substitutions for obsolete components were needed, the PCB design was updated to support SMD parts, and higher-quality components were specified, but the end result is essentially new amplifiers that are plug-in replacements for the original units. This should keep the telescopes on track for decades to come.
Not to sound jealous, but it seems like [Andrew] has a great gig. He’s shared a couple of his Keck adventures before, like the time a failed LED blinded the telescope. He’s also had a few more down-to-earth hacks, like fixing a dodgy LCD monitor and making spooky blinkeneyes for Halloween.