Blowing up a comet for the 4th of July

At around 06:52 – Lisbon Time - (or 05:52 UTC/GMT) the 4th of July, NASA's Deep Impact Mission is going to send an impactor to blow a hole in the "Tempel 1" comet.

The impactor is just a piece of metal with, more or less, the same size and shape of a small table.

Perhaps, in the future, people will look at this mission as the first trying to "explode" a comet, routine procedure to save the earth from catastrophic encounters (a subject science-fiction as visited several times, just remember the movie pictures: "Deep Impact" and "Armageddon”).

Since the internal structure of the comets is not know, there is no clear idea about what is going to happen and if the event would be seen from Earth (with a telescope).

Several other probes, beside “Deep Impact”, will try to collect info during the collision. The Hubble Space Telescope will take a snapshot.

There are not going to use explosives, but do not be fooled by that; with the velocity involved, and since the kinetic energy is proportional to de SQUARE of the velocity (i.e. each time you double the velocity, you multiply the energy by 4) the shock is going to be quite "explosive" (as everybody who as read "The Moon is an Harsh Mistress", my Robert A. Heinlein favorite book, know).

The velocity of impact is about 37 100 Km/h (30 times the speed of sound in the Earth surface). With 364 kg the impactor will reach to comet with almost 2E10 Joules of energy, the equivalent of around 5 tons of TNT.

Probably I will joint nuclio [ link: http://www.nuclio.pt ] to follow the event using a ESA satellite link (C-band?) . (Programs also available ay the internet)

The timetable (ESA TV):

*** 4 July

07:15 CEST (05:15 UTC/GMT) (06:15 Lisbon)
ESA TV live event (approx 60 minutes) based on NASA-TV plus studio interviews and inserts. with links to ESO, MPI Lindau (Rosetta), ESA/ ESAC (XMM/Newton) and ESA/ESOC (mission operations).

07:52 CEST (05:52 UTC/GMT) (06:52 Lisbon)
***** IMPACT *****

09:30 CEST (07:30 UTC/GMT) (08:30 Lisbon)
ESA TV update on European observations (approx 20 minutes).

10:00 CEST (08:00 UTC/GMT) (09:00 Lisbon)
NASA media briefing – live rebroadcast by ESA TV (approx 30 minutes).

18:00 CEST (16:00 UTC/GMT) (17:00 Lisbon)
ESA TV update with first Hubble image (black and white) (approx 20 minutes).

20:00 CEST (18:00 UTC/GMT) (19:00 Lisbon)
NASA media briefing – live rebroadcast by ESA TV (approx 30 minutes).

*** 5 July

06:00 CEST (04:00 UTC/GMT) (05:00 Lisbon)
ESA TV update with first ESO colour images

More links:

http://www.esa.int/SPECIALS/Rosetta/index.html

http://www.nasa.gov/mission_pages/deepimpact/main/index.html

ESA TV (Internet downlink guide):

http://television.esa.int

and see also "Things to watch" in the upper left corner of this blog.

UPDATE: (location)

http://maps.google.com/maps?q=lisbon+portugal&ll=38.778563,-9.114425&spn=0.005300,0.007124&t=k&hl=en

http://www.mapquest.com/maps/map.adp?latlongtype=decimal&latitude=38.77856&longitude=-9.11442

UPDATE2 – 28th of June: (picture on the top of this post) The comet from Hubble Space Telescope, in a picture taken in the 27th of June.

On the right we can see a natural burst from the comet. The result of the 4 o July impact may as well be like that.

http://www.nasa.gov/mission_pages/deepimpact/multimedia/tempel1-hst-062705.html