3 ms·
There's a great explanation of this on the astronomy stack exchange (https://astronomy.stackexchange.com/a/48317 https://astronomy.stackexchange.com/a/48317).
by muds 5y ago
There's a great explanation of this on the astronomy stack exchange (https://astronomy.stackexchange.com/a/48317 https://astronomy.stackexchange.com/a/48317).
- capableweb 5y agoSummary: - Available for observation for a prolonged time - A star that has just entered its field of view - Don't want a star in a field that is too crowded - The star should be bright, but probably not too bright