Tiangong-1 reentry updates

Latest reentry time window forecast provided by the Space Debris Office at ESA’s ESOC mission control centre, Darmstadt, Germany.

Note: Read our updated FAQ

Update 7 February 2018

The current estimated window is ~25 March to ~17 April; this is highly variable.

Reentry will take place anywhere between 43ºN and 43ºS (e.g. Spain, France, Portugal, Greece, etc.). Areas outside of these latitudes can be excluded. At no time will a precise time/location prediction from ESA be possible. This forecast will be updated approximately every week in January and February.

Current reentry time window forecast Credit: ESA

Current reentry time window forecast Credit: ESA

Current altitude deCurrent altitude decay forecast Credit: ESAcay forecast Credit: ESACurrent altitude decay forecast Credit: ESA

Current altitude decay forecast Credit: ESA 

Comments

8 Comments

  • T Zevo says:

    The parenthesis referring to spain, portugal, greece seems irrelevant to re-entry of tiangong between 43° north and 43° south!
    It seems that scientific community is rather casual about potential consequences of this un controlled re-entry situation.
    Little press on this for fear of embarrassing China?

  • John Kinahan says:

    People (e.g. Fox News) interprets your examples for 43 degrees N to 43 degrees S to mean Europe, and the continental US is not in its path… You should clarify this…

  • Viktor says:

    The positive side of that potential tragedy is more positions at space depris science.

  • CH says:

    Its amazing that these space stations are coming down and there is no back up system to blow them up..OR guide them ..
    I thought we all learned a lesson when sky lab came down about 30+ years ago..
    Its all well and good that there is more land and water, than populated areas. BUT , its going to come down somewhere and land on ONE grain of sand.. And what was the calculations on being that one grain of sand?
    it could as easily be the middle of a city.. A building full of thousands of people.
    If they put them up. There should be some way to deal with a re entry..
    Simpe ..Right?

    • Daniel says:

      Hi CH: We passed your comment to Holger Krag, Head of ESA’s Space Debris Office here at ESOC in Darmstadt, Germany. He replied as follows:

      Indeed, if it is shown that the on-ground casualty risk would be unacceptably high, most national guidelines recommend designing missions so as to enable a controlled reentry. A controlled reentry entails ensuring that the spacecraft or satellite has on board systems to lower its orbit by propulsive means, typically comprising a thruster and fuel, such that a specific geographical area on ground can be targeted. Most operators use a largely uninhabited area on the South Pacific Ocean.

      However, even if this is implemented in the design, in-flight failures could prevent such a controlled reentry and, hence, spaceflight will never be 100% risk free.

      When it comes to the actual risk associated with reentries, we have to say that from the about 30 000 tonnes of hardware that have re-entered so far, no casualty on ground has ever been confirmed.

      In fact, the amount of mass re-entering each year is, today, much lower than it was in the age of the Space Race in the 1970s and 1980s. In general terms, the likelihood of a person being hit by a piece of space debris is lower than the likelihood of being hit by lightning twice in the same year.

      Note that atmospheric break up will cause reentering objects, like satellites, to disintegrate into their constituent parts or components, small portions of which may survive to reach the surface. These will not all fall on the same spot, but rather will be dragged apart and will land with significant separations, typically on the order of over 100 km.

      Hence, the components of a complete spacecraft will never fall together into a city.

      Note also that the velocity with which these fall is much slower (typically < 300 km/hr) than, for example, a meteoroid. As a consequence, no crater is ever generated by falling space debris.

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