Looking for a new project, or just want to admire some serious mechanical intricacy? Check out [illusionmanager]’s Astronomical Clock which not only tells time, but shows the the positions of the planets in our solar system, the times of sunrise and sunset, the phases of the moon, and more — including solar and lunar eclipses.

One might assume that the inside of the Astronomical Clock is stuffed with a considerable number of custom gears, but this is not so. The clock’s workings rely on a series of tabs on movable rings that interact with each other to allow careful positioning of each element. After all, intricate results don’t necessarily require complex gearing. The astrolabe, for example, did its work with only a few moving parts.

The Astronomical Clock’s mechanical elements are driven by a single stepper motor, and the only gear is the one that interfaces the motor shaft to the rest of the device. An ESP32-C3 microcontroller takes care of everything else, and every day it updates the position of each element as well as displaying the correct time on the large dial on the base.

The video below shows the clock in operation. Curious its inner workings? You can see the entire construction process from beginning to end, too.

For many decades, the USA has been at the forefront of astronomy, whether with ground-based telescopes or space-based observatories like Hubble and the JWST. Yet this is now at risk as US astronomers are forced to choose between funding either the Giant Magellan Telescope (GMT) or the Thirty Meter Telescope (TMT) as part of the US Extremely Large Telescope (USELT) program. This rightfully has the presidents of Carnegie Science and Caltech – [Eric D. Isaacs] and [Thomas F. Rosenbaum] respectively – upset, with their opinion piece in the Los Angeles Times going over all the reasons why this funding cut is a terrible idea.

The slow death of US astronomy is perhaps best exemplified by the slow death and eventual collapse of the Arecibo radio telescope. Originally constructed as a Cold War era ICBM detector, it found grateful use by radio astronomers, but saw constant budget cuts and decommissioning threats. After Arecibo’s collapse, it’s now China with its FAST telescope that has mostly taken the limelight. In the case of optical telescopes, the EU’s own ELT is expected to be online in 2028, sited close to the GMT in the Atacama desert. The TMT would be sited in Hawai’i.

Of note is also that the TMT and GMT are both not solely US-funded at this point in time, but rather a partnership with a range of other nations, including Australia, Chile, South Korea, China, Canada, Japan, India and others. Even if the US only contributes funds to either telescope, the other partners may decide to pick up the slack, however the TMT project is currently in dire straits as the selected site on Mauna Kea has run into severe local resistance. This may force the TMT project to be sited elsewhere.

GMT and ESO’s ELT would seem to overlap significantly in terms of functionality and observed parts of the sky, making the TMT perhaps the most useful choice for US astronomers if they cannot have both. No matter what choice is made, however, it’ll mean more US budget cuts for astronomy and more US astronomers having to schedule observation time at EU and Asian observatories. Ultimately the USA as the guiding star in astronomy may significantly diminish, along with the positive effects of this status in the scientific community.

Although we have a gaggle of space telescopes floating around these days, there is still a lot of value in ground-based telescopes. These generally operate in the visible light spectrum, but infrared ground-based telescopes can also work on Earth, assuming that you put them somewhere high in an area where the atmosphere is short on infrared-radiation absorbing moisture. The newly opened Universe of Tokyo Atacama Observatory (TAO) with its 6.5 meter silver-coated primary mirror is therefore placed on the summit of Cerro Chajnantor at 5,640 meters, in the Atacama desert in Chile.

This puts it only a few kilometers away from the Atacama Large Millimeter Array (ALMA), but at a higher altitude by about 580 meters. As noted on the University of Tokyo project site (in Japanese), the project began in 1998, with a miniTAO 1 meter mirror version being constructed in 2009 to provide data for the 6.5 meter version. TAO features two instruments (SWIMS and MIMIZUKU), each with a specific mission profile, but both focused on deciphering the clues about the Universe’s early history, a task for which infrared is significantly more suitable due to redshift.