It’s a nice winter day in Minnesota today — but tomorrow the bottom drops out, and by Monday the forecast is so cold (high of -14 F) that Governor Dayton has ordered all public schools closed for safety reasons. And that’s up here where we’re sort of used to cold. The Arctic cold airmass will affect pretty much everything east of the Rockies, and that includes Virginia, home to the Antares launch pad at Wallops Island. With unusual cold and also rain in the forecast, Orbital Sciences has decided to wave off their Tuesday launch attempt. They are “preserving the option” of a Wednesday launch, but expect Thursday to be a more likely launch time. When it does fly, this will be the first operational Cygnus flight, with over a ton of cargo and 33 CubeSats hitchhiking on the Antares rocket. The launch will be carried live on NASA TV.