Rob,
For a person (plaintiff) to sue another (defendant) in relation to an injury, they must show that:
1. The defendant has a duty of care to the plaintiff
2. The defendant has failed in that duty ("negligence"), and
3. The defendant's negligence is responsible for the plaintiff's injuries.
In the example you have cited, the person (other than the would be plaintiff) with the only control over whether the injury occurs is the owner of the scope. The organisers of the starparty could not, on any analysis, have any control over such an incident. If the organisers can't control the incident, they can't be held to have failed in exercising a duty of care. Therefore, no case against the organisers.
Could the injured party sue the owner of the scope? Possibly. However, in NSW, the Court of Appeal has consistently held since October 2002 that persons must act reasonably to protect their own safety. It is for this reason that it is now virtually impossible in NSW to sue a Council because of the classic footpath trip and fall. The courts now say that people should know as a matter of common sense that footpaths are often uneven, and that they should be vigilent when taking a stroll. In like terms, amateur astronomers should know as a matter of common sense to approach a solar scope with extreme caution. A claim against the owner of the scope would almost certainly fail as well.
Before I was an industrial lawyer, I ran many hundreds of personal injury cases, firstly acting for insurers like Zurich and QBE, and later for injured persons. I have been in PI cases ranging in value from $10K to $3.5million. If the model that we are following is that we are an informal community, and not an organisation, I remain of the view that we will not be able to obtain insurance, and that we have no need to do so. Our star party will be no different to a group of mates getting together for a beer after work. We will all be equals, meeting together to pursue our mutual interests.
Here endeth the lesson.
