A stellar wind is a flow of gas ejected from the upper atmosphere of a star. It is distinguished from the bipolar outflows characteristic of young stars by being less collimated, although stellar winds are not generally spherically symmetric.
Different types of stars have different types of stellar winds.
Massive stars of typesO and B have stellar winds with lower mass loss rates ( solar masses per year) but very high velocities (v > 1–2000km/s). Such winds are driven by radiation pressure on the resonance absorption lines of heavy elements such as carbon and nitrogen. These high-energy stellar winds blow stellar wind bubbles.
The program's activities involved data mining of a large database of the communications of American citizens, including e-mail communications, telephone conversations, financial transactions, and Internet activity.William Binney, a retired technical leader with the NSA, discussed some of the architectural and operational elements of the program at the 2012 Chaos Communication Congress.
The intelligence community also was able to obtain from the U.S. Treasury Department suspicious activity reports, or "SARS", which are reports of activities such as large cash transactions that are submitted by financial institutions under anti-money laundering rules.