I think/hope that this is on-topic due as it can relate to spurious visual satellite sightings. According to the following NOAA Web site, USA weather balloons two meters in diameter are launched twice per day every day, usually at 00:00 and 12:00 UTC: http://www.nws.noaa.gov/er/gyx/weather_balloons.htm It says that they can reach an altitude of 35 km and drift 200 km in flights lasting up to two hours. I'm not sure what all types of research balloons might be launched in the USA for other purposes, but there is a Web site for the National Scientific Balloon Facility (NSBF): http://master.nsbf.nasa.gov/ One of the pages on their site includes this statement: "Today, payloads weighing 5000 pounds are quite common and balloons of 20 to 30 MCF are flown routinely." ("MCF" means million cubic feet, a unit for measuring the volume of the [inflated] balloon.) I don't have any idea how often "routinely" means. The time or two that I've seen one of the large balloons, they have been very impressive! But that was long before I got into watching satellites. I have no idea about balloons used by other countries, although perhaps there's information online. I know I've read recently about Australian research balloon flights. Ed Cannon - ecannon@mail.utexas.edu - Austin, Texas, USA ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www2.satellite.eu.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Fri May 25 2001 - 16:54:43 PDT