A number of questions have come into ESA’s NEO Coord Centre, ESRIN, Italy, concerning the forecast reentry on 13 November of an unknown object designated WT1190F (see: Reentry data will help improve prediction models).
The rare reentry of a suspected rocket body from a very high orbit offers an excellent opportunity to gather data to improve our knowledge of how objects interact with Earth’s atmosphere. The reentry poses very little risk to anyone but could help scientists improve our understanding of how any object – man-made or natural – interacts with Earth’s atmosphere.
It is now predicted to reenter Earth’s atmosphere around 06:19 GMT (11:49 local; 07:19 CET) on 13 November 2015. A significant fraction if not all of it can be expected to completely burn up in the atmosphere; whatever is left is expected to fall into the ocean about 100 km off the southern coast of Sri Lanka.
One question that has come in is, What uncertainties can be expected for the reentry, and will it be visible?
ESA’s NEOCC answers:
It is not easy to predict from where the reentry might be visible, because it’s unclear how far up in the atmosphere the object would start to disintegrate, and this is reflected in an uncertainty in the actual re-entry point of as much as 100-200 km.
Being local noon in the area, only the brightest part of the trajectory may become observable. We would therefore expect observations to be possible from land only from the southern province of Sri Lanka; Colombo, the capital of Sri Lanka, is ~200 km away, which may be a bit too far.
ESA NEO Coordination Centre team