Archive for May 16, 2020

The Geostationary Orbit

Posted in Cute Problems, The Universe and Stuff with tags , , , on May 16, 2020 by telescoper

I’m was mucking out this blog’s blocked comments folder and unsurprisingly found a few from Mr Hine, a regular if sadly deranged correspondent.

One of his blocked comments begins

In the forlorn hope that Mr Hine might some day learn something scientifically correct I thought I’d repost this problem, which is very easy if you have a high school education in physics or applied mathematics but no doubt very difficult if you’re Mr Hine.

Verify that the radius of a circular geostationary orbit around the Earth is about 42,000 km, i.e. find the radius of a circular orbit around the Earth which has a period of 24 hours so that its orbital period matches the Earth’s rotation period, thus ensuring that an object travelling in such an orbit in the same direction as the Earth’s rotation is always above the same point on the Earth’s surface.

(You will need to look up the mass of the Earth.)

Phase 1 Approaches

Posted in Biographical, Covid-19, Education, Maynooth with tags on May 16, 2020 by telescoper

Yesterday (Friday 15th May) the Government of Ireland announced that Phase 1 of the Roadmap for relaxation of its Covid-19 restrictions would commence as planned on Monday 18th May.

This won’t make a huge difference to those people working in third level institutions because it means that anyone who can work from home should continue to do so. As you can see in the graphic above, though, some (limited) access to buildings will be available to allow staff access “to facilitate remote learning”.

Here at Maynooth University our teaching term is over and we’re into the examination period, so there is no actual teaching going on. There are exams, however, and some staff (including myself) will be going onto campus to oversee these, including sitting by their office phones in case of emergency. It is a great relief that we can do this during the examination period as things would have been far more complicated otherwise, especially for those of us who don’t have full internet access at home.

Access for this purpose will be strictly limited and in general the campus is not open. The rules for those coming into campus are quite strict. These are excerpts from the instructions sent out by the University last night:

  • Everyone who can work effectively from home should continue to do so, and non-essential travel should not be undertaken.
  • The campus is not open, and there is no general access, but you may access your office in limited circumstances if you cannot otherwise prepare for or deliver remote teaching and assessment. Approval from your Head of Department is required in all instances.
  • Always observe physical distancing of 2m and ensure thorough hand hygiene. These are key individual responsibilities to minimise the spread of the virus.
  • Employees should wash their hands when they arrive and leave.
  • Essential access will be limited to an individual’s office, provided it is not shared. If you work in a shared office, you should co-ordinate with your colleagues to make sure that you are not there at the same time.
  • There will be no general access to any shared facilities, except toilets. Toilets will be cleaned every evening, but it is the responsibility of every individual to ensure personal hand hygiene on leaving the toilets.
  • Anyone who does require access to their office should make their way directly to their office and avoid congregating in groups. Once the essential work is complete, you should leave the campus directly.

A more general ‘return-to-work’ will start in Phase 2 (in three weeks’ time) but several things related to health and safety will need to be organised before that. In the meantime I expect the Department of Theoretical Physics will continue to be empty apart from occasional visits by myself and one or two other members of staff.

Anyway, we need to take life one phase at a time. My main priority on Monday will be trying to remember where my office is, as I haven’t been there for nine weeks!

P. S. Schools in Ireland will not reopen until the start of the new school year, in August.