Welcome to the website for the 2012 TC4 Observing Campaign. Our intention is to provide a central clearinghouse for basic information about the near Earth asteroid 2012 TC4 and about the observations that will be obtained during its upcoming apparition.

This site will contain background information about 2012 TC4, a list of observations that are planned/scheduled/obtained, and status reports on the events leading up to the close approach. We will also produce an email list where updates can be broadcast to subscribers.

What is special about 2012 TC4?

2012 TC4 is a near-Earth asteroid discovered in 2012
It has the potential to get very close to the Earth, but its orbit is currently not very well determined, having been derived from only a 7 day arc from 2012. Thus, there is significant interest in observing it this fall to improve its orbit, so that future Earth encounters can be investigated.
2012 TC4 makes a very close approach to the Earth this fall
On 12 Oct 2017, it will pass within the orbit of the Moon, At closest approach, it will be ~83,000 km from the surface of the Earth (based on the current orbit, which will change with improved astrometry after it is recovered.)
Observing conditions vary through the encounter
During its approach to the Earth, the observing conditions are good (near opposition for ~2 months, with Earth-facing surface mostly illuminated). After passing the Earth, however, it will be difficult to observe (small solar elongation, with most of the Earth-facing surface in shadow).

Updates & News

2017.08.06: 2012 TC4 recovered by VLT observers! See 2017 Apparition for details.

2012 TC4 observed Credit: ESO / ESA NEOCC / Olivier Hainaut (ESO), Marco Micheli (ESA) and Detlef Koschny (ESA) Details: 2012 TC4 observed (annotated)

Credit: ESO / ESA NEOCC / Olivier Hainaut (ESO), Marco Micheli (ESA) and Detlef Koschny (ESA)

Related releases:
A Very Close Encounter

Mailing List

We are maintaining an email list for broadcasting occasional updates regarding the 2012 TC4, and for making announcements regarding short-term transient events that might prompt follow-up observations.

If you want to be added to (or removed from) this list, then send your name, affiliation and email address to the Contact Web Form