Reading the sky, and what copper can do for you
Tonight: finding the planets by eye, growing a blue crystal over months, and the limits of a fanless PC.
Three threads run through tonight's issue, and none of them needs a working grid. One asks you to look up and name the planets by eye. Two put copper on a workbench: grow it into a blue crystal, or bend it into pipe that carries heat. Together they are a small lesson in what a person can still do with patience, a clear night and a few cheap materials.
EarthSky published its October 2026 night sky guide on October 5, written by Marcy Curran. It lists Jupiter as the brightest planet in the morning sky, next to red Mars and Saturn, while Venus and Saturn hold the evening. Venus disappears early in the month. Saturn brightens and stays up all night. On the morning of October 6, the guide says, the waning crescent moon lies near Jupiter, Mars and the Beehive star cluster, and observers across much of the US, Mexico, the Caribbean, southeast Canada and parts of Africa can watch the moon pass in front of Jupiter around 10 UTC.
More comes later in the month. On October 11, EarthSky says, Mars passes through the Beehive cluster in Cancer, between the bright stars Regulus, Pollux and Castor. Venus reaches inferior conjunction on October 23-24, which ends its run as an evening object. For star clusters and fainter targets the guide recommends binoculars, and it points readers to Stellarium Online for precise times from their own location rather than its general charts.
Copper sulfate crystals are probably among one of the prettiest crystals you can grow at home, Hackaday's Maya Posch wrote on October 5, describing a method from the channel Crystalverse. It starts with a saturated solution made with near-boiling water, with slightly more copper sulfate than will dissolve, so crystallization sites form on the bottom of the jar and draw growth away from the main crystal. A seed crystal is then suspended in the solution.
Large crystals take months, the article says. The temperature stays as constant as you can keep it, competing crystals get weeded from the bottom, and slower growth gives better results. You can buy copper sulfate directly, sold as a fungicide or root killer. A home mix of copper scrap and vinegar yields copper acetate, not copper sulfate. The crystal's deep blue comes from water held inside it, and it turns white as it dries out.
The third thread is a caution. Hackaday's Fenix Guthrie wrote on October 5 about Billet Labs' attempt at a silent, fanless gaming PC. Modern components are highly efficient at producing monumental quantities of thermal energy, the piece notes. The builders used an aluminum block as the case base, with thermal paste and pads pulling heat from the motherboard and graphics card. Then they soldered a water-cooling loop from household copper pipe and stacked three radiators to encourage natural airflow.
It wasn't enough. The stacked radiators could not keep the machine cool under a gaming load, and water flowing past the pressure gauge was noisy. Removing the gauge and adding a single 120mm fan between two of the radiators fixed both problems and produced a quiet PC. Passive cooling carried most of the weight. One small fan carried the rest.
Sources
- Visible planets and night sky guide for October · EarthSky, Tonight
- How to Grow a Giant Crystal from Copper Sulfate · Hackaday
- Failing to Make a Fanless PC · Hackaday