I didn't know it's from a magazine.

I continue to learn correct usage of the English language.

The main difference between the two is that 'although' is slightly more formal.

Your quote is from the website of the Colorado School of Mines, and the page is written in a 'chatty' (informal) style. As you can see, the writer uses the less forMal 'though'. So either of the words could start a sentence.