rosetta media briefing 16 october 2014 - dr. gerhard schwehm, former rosetta mission manager &...

Gerhard Schwehm & Matt Taylor

and the Rosetta SWT

Rosetta: Science at Comet 67P/Churyumov-Gerasimenko

Lowry et al., 2012

Lamy et al., 2007

Vincent et al 2013

C67P/Churyumov-Gerasimenko

How we imagined the comet before the arrival

Lowry et al., 2012

Lamy et al., 2007

Vincent et al 2013

C67P/Churyumov-Gerasimenko – the Fiction

C67P/Churyumov-Gerasimenko – the Reality

Mass ~ 1013 kg

Volume ~ 25 km3

Density ~ 0.4g/cm3

Rotation ~ 12.4 hour

Mass ~ 1013 kg

Volume ~ 25 km3

Density ~ 0.4g/cm3

Rotation ~ 12.4 hour

Comet nucleus

Mass ~ 1013 kg

Volume ~ 25 km3

Density ~ 0.4g/cm3

Rotation ~ 12.4 hour

Comet nucleus

More recently - Temperature variations across regions and with local time. average ~ -70o C , peaking -40o C

ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

ESA/Rosetta/Navcam

Comet nucleus

‘Cheops’

ESA/Rosetta/Navcam

ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Comet nucleus

ESO/ESA Snodgrass et al., 2014

19,000 km

Comet activity and coma

19,000 km

ESO/ESA Snodgrass et al., 2014

Comet activity and coma

Comet activity and coma - gas

ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

“selfie” taken Sept. 8th from Philae,

still attached to the Orbiter, with

our target comet at 50 km

ESA/ROSETTA/PHILAE/CIVA

Sss

Selfie from 16 km Composite Image

ESA/ROSETTA/PHILAE/CIVA

COSIMA GIADA

Comet activity and coma - dust

1 cm

Total number densities measured by

ROSINA-COPS

The density varies with the rotation period

and the latitude (summer/winter) of the

comet due to illumination from the Sun

15 20 25 30 35 40 45 50

0

20000

40000

60000

80000

100000

120000

CO2

CO

row A_22-08-2014

row A_01-08-2014

ion

num

be

r

m/z

H2O

Distance of Rosetta from

67P/CG

01-08-2014 10:15 =>

885km

22-08-2014 13:50 => 61

km

Distance from Rosetta to

the Sun

01-08-2014 => 3.6 A.U.

22-08-2014 => 3.5 A.U.

DFMS – first results on chemical composition

Nu

mb

er

of

ion

s i

n 2

0s

Major species

High resolution neutral mass spectrum

of mass 28 Da

Conclusions: the

perfume of C-G

There are a lot of sulfur species in the coma

The comet smells of rotten eggs

There is ammonia in the coma

The comet smells like horse droppings

There are a lot of acids, alcohols, hydrocarbons

The perfume of C-G is very special, but

interesting

Comet activity and coma - plasma