Helium-3, writes David Kramer, “occurs at a ratio of 0.2 parts per million of 4He.” However, according to the International Union of Pure and Applied Chemistry,
1
the natural abundance of 3He is 1.37 ppm. Otherwise, the article was excellent.
The Week in Physics" is likely a reference to the regular updates or summaries of new physics research, such as those found in publications like Physics Today from AIP Publishing or on news aggregators like Phys.org.