- Messier 91 (also known as NGC 4548 or M91) is a barred spiral galaxy that is found in the south of Coma Berenices. It is in the local supercluster and is part of the Virgo Cluster of galaxies. It is about 63 million light-years away from our galaxy. It was the last of a group of eight “nebulae” – the term ‘galaxy’ only coming into use for these objects once it was realized in the 20th century that they were extragalactic – discovered by Charles Messier in 1781. It is the faintest object in the Messier catalog, with an apparent magnitude of 10.2.
- MICROSOFT GW-BASIC User’s Guide and Reference (PDF) (computerhistory.org)
Microsoft® GW-BASIC® is a simple, easy-to-learn, easy-to-use computer programming language with English-like statements and mathematical notations. With GW-BASIC you will be able to write both simple and complex programs to run on your computer. You will also be able to modify existing software that is written in GW-BASIC.