Cassiopeia through the trees
- I saw Casseopeia in the northeastern sky between two evergreen trees. I wondered, if we observe a star, are we getting photons that bounced from more distant stars and planets, perhaps even an older Earth?
- Silicon dioxide (Wikipedia)
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula SiO2, commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a synthetic product. Examples include fused quartz, fumed silica, opal, and aerogels. It is used in structural materials, microelectronics, and as components in the food and pharmaceutical industries. All forms are white or colorless, although impure samples can be colored.
- 2022-08-28 21:05:00 -0700