Get the Image of the Day and learn something new at NASA's Earth Observatory website
The NASA Earth Observatory has an Image of the Day page with free downloadable .jpg images. Most are related to the Earth and the environment, and have accompanying information about the subject of the image. The images aren't all the same size and are good for general use, and some are large enough (and nice enough) for wallpapers.
The Earth Observatory's mission is to share with the public the images, stories, and discoveries about the environment, Earth systems, and climate that emerge from NASA research, including its satellite missions, in-the-field research, and models. It's been keeping an eye on the Earth and the environment since 1999. The site has a wealth of data in the form of maps, articles and datasets.
If you want to see more of the site, the Topics drop down menu has nine categories to explore. Atmosphere, heart, humans, land, life, natural events, remote sensing, snow and ice, and water have individual categories. Similar to NASA's Astronomy Picture of the Day and the NASA Image of the Day, the site hosts great photos and interesting commentary. You can get the image of the day sent to your Inbox via their newsletter if you prefer.
Note: if you want to download the NASA Image of the Day, click on the photo, then on the downward pointing arrow next to the title of the photo. If you use an ad blocker, the download arrow may not be visible. Whitelist the site in your ad blocker and reload the page, it should appear.
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