The Sunspot Cycle and its Possible Effects on Future Manned Spaceflight

We have known for more than a century that solar activity shows a pronounced cyclic variation with an 11-year period. About every 11 years there is a maximum in activity and sunspots become very prominent and very common. Back in my younger days, I was a keen solar observer during one particular holiday around the [...]

How many Apollo astronauts are still alive?

One of the greatest features of a Herschel mission lunch in the canteen – although most of the Herschel veterans around the table have now moved on to other missions – is the remarkable conversations. A topic comes up and a bunch of scientists and engineers start ruminating on it. These days the topic is [...]