- Iota-1 Scorpii (stars.astro.illinois.edu)
IOTA-1 SCO (Iota-1 Scorpii). Supergiants are rare, and to find two of them within a quarter-degree of each other is rarer still. To find two forms of supergiants that for the class are rare in themselves draws the eye, or at least should. Nevertheless, these two magnificent stars, which have no proper names and are known as Iota-1 (the western and brighter) and Iota-2 Scorpii, are quite neglected, perhaps by contrast to Scorpius’s brighter magnificent stars, which include one of the most prominent of all supergiants, Antares.
- Chemical compound (Wikipedia)
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed.