The anatomy of an asteroid: Asteroids can have a highly varied internal structure

This kind of research is of fundamental importance for asteroid mining.

After Big Bang

ESO’s New Technology Telescope (NTT) has been used to find the first evidence that asteroids can have a highly varied internal structure. By making exquisitely precise measurements astronomers have found that different parts of the asteroid Itokawa have different densities. As well as revealing secrets about the asteroid’s formation, finding out what lies below the surface of asteroids may also shed light on what happens when bodies collide in the Solar System, and provide clues about how planets form.

Using very precise ground-based observations, Stephen Lowry (University of Kent, UK) and colleagues have measured the speed at which the near-Earth asteroid (25143) Itokawa spins and how that spin rate is changing over time. They have combined these delicate observations with new theoretical work on how asteroids radiate heat.

This small asteroid is an intriguing subject as it has a strange peanut shape, as revealed by the Japanese spacecraft Hayabusa in…

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Exit visas and international child abduction

In the modern world only a few countries, mostly with dictatorial governments, require their citizens or residents to buy a visa for leaving the country. Most countries only require foreigners to buy a visa for entering the country.

Since the freedom of movement, including the right of leaving one’s own country at will, is considered a fundamental human right, most civilized nations consider a general restriction on departing one’s country as an abomination. Only in a few serious cases (e.g. of convicted criminals or people awaiting trial), it’s nowadays acceptable for a state to put restrictions on their citizens’ freedom to leave the country.

This is all fine for adults who are capable to decide for their own whether they will leave the country or not. There’s these days, however, a huge problem of international child abduction. It’s our opinion that an exit visa requirement for minors can be an effective measure to combat international child abductions.

In most cases of international child abduction, a non-custodial parent take his or her own child to another country against the will of the custodial parent. Usually the motive is the result of a failed marriage or another intimate relationship and a subsequent custody battle between the parents.

The system we propose will works as follows. All minors, defined as all persons below the age of sixteen years, who will travel to a foreign destination are required to be in the possession of an exit visa. Only the custodial parent is authorized to apply for this exit visa, which does not mean that a child cannot travel with his non-custodial parent, it only ensures the permission of the custodial parent.

On the application form the custodial parent will declare the minor’s destination (multiple destinations are possible), the duration of the stay abroad, whether the child will travel alone or in company of an adult, and in the latter case with whom.

In order to ensure the cooperation of foreign countries, the passport of minors should contain instead of “valid for all countries”, the phrase “valid only with appropriate exit visa”. The subsequent effect of this measure, is that expiration of the exit visa, the minor will automatically remain illegal in the foreign country, and hence the authorities are obliged to extradite the minor back to his or her home country. And the person, mostly the non-custodial parent, can be charged of harboring an illegal immigrant.