A Windows theme consists of desktop wallpaper, a colour scheme for windows, borders, buttons and so on, and sounds for system events. Microsoft has a collection of high quality themes on its website and there are three that are of interest to astronomers:
Click the links to go to the web page and click the Download theme button. Open an Explorer window and go to the Downloads folder. Double click a theme file to install it and activate it.
The last theme you install will remain as the currently selected one, so to switch to one of the others, right click an empty part of the desktop and select Personalize. Click a theme and it is automatically applied. It takes a couple of seconds, so don’t assume it has not worked if it does not instantly change.
Click Desktop background at the bottom and you can see all the images used in the theme. The images automatically change on a schedule and you can select the time each one is displayed for at the bottom. Select from every 10 seconds (a bit silly, but possible), to one day.
Just above the images in this window is Picture location and there is a Browse button to the right. You can select any folder on the disk drive that contains images and the theme will use them and automatically cycle through them according to the schedule.
This is a useful feature and if you go to the NASA Jet Propulsion Laboratory website there are hundreds of space images organised into categories like Sun, Mercury, Venus, and the rest of the planets, dwarf planets, asteroids and comets, the universe, and spacecraft and technology.
Select a category, click a thumbnail and a page opens that shows a larger version of the image and download links. There are seven different image sizes. Right click the one that is closest to the Windows desktop resolution and select Save link as or Save target as, depending on which browser you use.
Download as many space images as you want, then open an Explorer window and go to the Downloads folder. That’s where all the images are. I created a NASA folder in my Pictures folder and moved them there. Then you can click the Browse button in the desktop background window and select the folder.
Here you can see all the images I downloaded. Select them all or just tick the ones you want to use. Select the Change picture every schedule, tick Shuffle if you want, and click Save changes. The desktop now uses those NASA space images you downloaded.
It is good fun to download Windows themes and to customise them with your own images. Try it and see.