February 2023 Archives

Inevitable Improbabilities

Guys anything can happen. There is literally no way of avoiding something that you haven’t prepared for. So in the face of mounting anxiety over the huge number of unexpected scenarios that may be around the corner, what can you do? You can contemplate insulating yourself, try and minimise the hazards, control your environment to a fine level of detail so that the surprises are infrequent and hazards are mitigated. At work I am drowned in Health and Safety Guidance, IT security protocols, Fire Safety Training. This means that work is to a large extent a somewhat boringly protected environment for me, my colleagues and my patients. Yet, even this can not avoid surprises. So what about your home, sitting in front of your computer. All the protection provided by protocols here are more vague, less policed, seen more as guidelines rather than mandatory.

The worst enemy

Being left to your own devices is perhaps one of the most dangerous situations to find yourself in. I find it difficult to imagine there to be a more extreme difference between the personal perception of safety and the severity of potential calamities in these circumstances. It is therefore incumbent upon those with idle time, to utilise that time to create simulations to prepare for the unexpected apocalypse around the corner. The probability that one may find one’s self having become lost, ending up 400,000km away in an experimental lunar lander may be extremely small, but possibly not zero. There may be small risk that the lander’s automatic attitude and thrust controllers have become inoperative requiring manual control to land the craft in terrain that is not generally flat. Even if it is extremely unlikely, one might find this endeavour to be made more hazardous by previously undetected vacuum breathing aliens, also orbiting the moon. Got to be ready.

The right attitude

Rocket science this ain’t.

An orbiting landing module may have a transit roughly parallel to the surface of the satellite. In order to descend the lander would need to use thrusters to slow the craft facing away from the direction of travel; this decreases the forward motion, the craft descends to a lower orbit adding a motion vector in the direction of the surface of the planet, and gravitational forces start the acceleration towards the ground. to fast an approach makes the next burst of thrust directed at both slowing the forward velocity as well as the rate of descent. Once the forward velocity is reduced enough the loss of centripetal forces means the vehicle is now experience the full force of lunar gravity, and the right amount of downwards thrust is now required the safely land the vehicle

Earth’s last hope

The initial landing may hopefully avoid the orbiting space monsters; the craft is unarmed, as one might expect from rocket engineers who failed to consider the evidence from countless movies on this subject.. Whilst on the lunar surface I would need to build a regolith cannon to fight the aliens, whose next target would potentially be earth. Humanity would be counting on me to suppress this invasion or die trying. Wish me luck, guys, I am getting ready.

About Saif

user-pic An Orthopaedic Surgeon, A Tissue Engineering Scientist, Lecturer, (and Hobbyist Programmer, Electronics Engineer and Roboticist)