Rosetta: getting close and personal with a comet

Matt Taylor, on behalf of the entire Rosetta community

A follow up to ESA's first deep space mission, Giotto

Halley, ESA/MPAE, 1986, 1996

Giotto at Halley

Distance 1430 km, resolution 100 m (comet 13 km long)!

Me in 1986

Courtesy of G. Jones, MSSL/UCL

Rosetta

Philae temple of Isis The Rosetta Stone

The combination of the Rosetta Stone and the Philae obelisk were key in deciphering the hieroglyphs and

unlocking the secrets of the civilisation of ancient Egypt.

Fly by’s - 100’s km 10’s km/s

Comet observations Spacecraft visits (imaged...)

•  Spacecraft Visits to Comets (imaged) •  The Halley Armada

• Giotto, Vega 1 and 2, Suisei, Sakigake

•  Deep Space 1 (Borrelly) •  Stardust (Wild 2) •  Deep Impact (Tempel 1) •  EPOXI (Hartley 2) •  Rosetta (C-G)

Comet observations Spacecraft visits (imaged...)

•  Spacecraft Visits to Comets (imaged) •  The Halley Armada

• Giotto, Vega 1 and 2, Suisei, Sakigake

•  Deep Space 1 (Borrelly) •  Stardust (Wild 2) •  Deep Impact (Tempel 1) •  EPOXI (Hartley 2) •  Rosetta (C-G)

<< 100 km at m/s

Rosetta- 2.8 m x 2.1 m x 2.0 m

32 m Philae - 0.85m x 0.85m (1.3 high and 1.46 m legs)

Rosetta Primary Mission Goals • Catch comet 67P/Churyumov-Gerasimenko in 2014 and accompany it into the interior solar system. • Observe the comet’s nucleus and coma from close range. • Measure the increase in cometary activity during perihelion. • Deploy a robotic lander to make the first controlled landing on a comet nucleus. !

Primary Science Goals •  Create a portrait of the comet’s nucleus •  Take a complete inventory of the comet’s composition. •  Detail the comet’s physical properties •  Examine the evolution of activity •  Explain the comet’s origin •  Create portraits of two asteroids

Rosetta Full suite of insitu and remote sensing instruments

Camera (250–1000nm) Wide-angle (12° FOV) Narrow angle (2.5° FOV) UV spectrometer (70–205nm) VIS and IR mapping spectrometer (250–5000nm) Microwave spectrometer

OSIRIS (H. Sierks, DE) ALICE (A. Stern, US) VIRTIS (F. Cappacioni, IT) MIRO (S. Gulkis, US)

Rosetta

Neutral gas- and ion mass spectrometer Chemical composition of gas in coma Solid mass spectrometer Chemical composition of coma dust Atomic force microscope Shape and size of dust grains

ROSINA (K. Altwegg, CH) COSIMA (M. Hilchenbach, DE) MIDAS (M. Bentley, AT)

Rosetta

Radio transmitter on lander and receiver on orbiter Tomography of nucleus Grain impact analyser and dust collector Rosetta plasma consortium Five plasma instruments Radio science investigation

CONSERT (W. Kofmann, FR) GIADA (A. Rotundi, IT) RPC (Several PI’s) RSI (M. Pätzold, DE)

Rosetta

Philae

Alpha X-ray spectrometer: composition

Six micro-cameras: surface imaging

Radio tomography of nucleus

Evolved gas analyser: organics

Evolved gas analyser: isotopic ratios

Probe on anchor: structure, properties

Imaging system: descent and landing

Magnetometer/plasma monitor

Drill to 20cm: deliver to analysis ovens

Probes comet outer layers

APXS

ÇIVA

CONSERT

COSAC

PTOLEMY

MUPUS

ROLIS

ROMAP

SD2

SESAME

Philae

Rosetta science Comet nuclei Overall, all look different: Different formation or different evolution?

1P/Halley: Highly active, low albedo, relatively little geological information about the surface 19P/Borrelly: Diverse geology, different types of terrain, no ice found on surface! 81P/Wild: Rugged terrain, impact craters ? 9P/Tempel 1: Diverse terrain, primordial layers found?, impact craters ?, very little ice found on surface 103P/Hartley 2: Hyperactive, diverse terrain, extreme shape, ice blocks (cm-dm sized) emitted from nucleus

Rosetta science Comet nuclei Overall, all look different: Different formation or different evolution?

Icy conglomerate Fluffy aggregate

Rubble pile Icy glue

Primodial layers

Nucleus structure

•  Cameras will provide images down to 10’s cm resolution: Structural differences will become visible •  CONSERT will study the interior structure of the nucleus •  Lander will provide ground truth at one position on the nucleus

Rosetta science

Cometary activity - How does the sublimation process work ? How are dust grains accelerated by the gas ?

Rosetta science

• Images and spectra taken of active regions at dm – m scales near nadir (surface) and at the limb (inner coma) Will help understand interaction surface-> coma

• Near-IR and sub-mm spectra will investigate presence of surface ice at high resolution

• ROSINA will measure the gas production and composition throughout the orbit

• GIADA will measure the dust flux and size distribution throughout the orbit Largest sizes may be accessible through imaging

• MIDAS will measure the structure of individual dust particles • COSIMA will measure the composition of individual dust

particles • Lander will provide full information at one point on the surface (if landing on an active area)

How does cometary activity work?

Rosetta science

From Ip and Axford, (1986) STEREO: 2P/Encke, Tail disconnection

•  Induced magnetosphere formed by dust - gas emission interaction with solar wind

•  Field draping and ion pick up •  RPC + ROMAP

Rosetta science

• ROSINA will measure the composition of many species and isotopes, incl. D/H Orders of magnitude more sensitive composition measurement than anything before

• Lander will provide composition and isotope ratios for nucleus material at one point of the surface

• Additional composition information from remote sensing instruments

Composition

Rosetta science

Discovery Perihelion Aphelion Semi-major axis Eccentricity Inclination Orbital period

1969 1.2458 AU 5.6839 AU 3.4648 AU 0.64043 7.0424° 6.45 yr

Klim Churyumov, Jean-Jacques Dordain (ESA), & Svetlana

Gerasimenko at Rosetta launch

Credit: MPS http://www.mps.mpg.de/en/aktuelles/pressenotizen/pressenotiz_20130820.html

Target: 67P/Churyumov-Gerasimenko

Reconstruction of light-curve data rotation rate ~12.7 hours

Lowry et al., 2012

Lamy et al., 2007

Target: 67P/Churyumov-Gerasimenko

Rosetta so far

Launch 2 March 2004 ���First Earth swing-by 4 March 2005���Mars swing-by 25 February 2007���Second Earth swing-by 13 November 2007���Steins fly-by 5 September 2008���Third Earth swing-by 13 November 2009���Lutetia fly-by 10 July 2010���Hibernation Entry 8 June 2011

First Earth !y-by

NavCAM image on March 4, 2005 / ESA

Rosetta so far

Eastwood et al., JGR, 2011

First Earth !y-by Rosetta so far

Rosetta so far

Rosetta at Mars

As seen at 240,000km, one day before fly-by on February 25, 2007 / ESA

Rosetta so far

Near closest approach at 1,000km, February 25, 2007 / ESA

Rosetta so far Rosetta sel"e at Mars

Edberg et al., 2009a+b

Rosetta so far

Near simultaneous observations by Rosetta and Mars Express. Bow shock found closer to planet than expected. 2 point measurements revealed high pressure solar wind pulses to cause asymmetry in the plasma boundaries.

Rosetta at Mars

thanks N. Howes

Asteroid 2867 Šteins Rosetta so far

Fly-by on September 5, 2008

Asteroid 2867 Šteins •  Unlocked physical properties of this main-belt asteroid. •  Loosely-bound 'rubble pile' whose diamond shape has been honed by

the YORP effect, the modification of rotation rate from IR emission and momentum, redistribute material towards the equator of the object (landslides!)

•  This is the first time this effect has been seen in a main-belt asteroid.

5.9 x 4 km, from 800 km at 8.6 km/s H. U. Keller, et al., Science, 2010

ESA ©2008 MPS for OSIRIS Team MPS/UPD/LAM/IAA

ESA ©2009 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

ESA ©2009 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

Hurley et al., 2014

Asteroid 21 Lutetia

H. Sierks, et al., Science, 2011

More than 350 craters were identified with diameters between 600 metres and 55 km and depths of up to 10 km, ~3.6 billion years old

121 km x 101 km x 75 km from 3170 km at 15 km/s

Asteroid 21 Lutetia

Movie made from images taken by OSIRIS, released May 30, 2012 / OSIRIS, ESA

Asteroid 21 Lutetia

Fly-by on July 10, 2010

• 21-km diameter crater cluster close to the north pole. • Most of the ejecta from the initial impacts seems to have failed to reach escape velocity and fallen back to the surface. ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

Copyright ESA 2011 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA and Yuri Beletsky / ESO

And ....sleep.... In the meantime, back on Earth...

http://www.rosetta-campaign.net/

Ground based support and observations of CG 67P

October 2013

ESO/C. Snodgrass (Max Planck Institute for Solar System Research, Germany)

Pro-Am collaborative Astronomy Group Padma A. Yanamandra-Fisher: Flickr, Pinterest, Facebook, twitter

Rosetta Working Group X provides modelling support to the project http://ices.engin.umich.edu/index.php

20 January 2014

Ramp up of outreach campaign - wake up competition

20 January 2014 Hibernation exit.... and an ear worm....

1971 Top of the Pops

Alan Price and Georgie Fame - Rosetta

“Rosetta, are you better? are you well?”

Keep up to date: @ESA_Rosetta

Rosetta blog http://blogs.esa.int/rosetta/

• Nearly 500,000 people watched wakeup • #rosetta and #wakeuprosetta •  32.295 tweets by 18.513 contributors with a reach of 75.11 million people, within 24 hours around the wake up.

Where are we now

Navigation camera - 23 February 2014

Rosetta 2014-2015

ESO- VLT

ESO VLT 28 February 2014

ESO/C. Snodgrass (Max Planck Institute for Solar System Research, Germany) & O. Hainaut (ESO)

Including first light from OSIRIS Wide Angle Camera

around 5 million km from 67P ESA © 2014 MPS for OSIRIS-Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

around 5 million km from 67P ESA © 2014 MPS for OSIRIS-Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Including first light from OSIRIS Narrow Angle Camera

M107

VLT image - 7 May 2014

VLT image - 7 May 2014

OSIRIS NAC

27 March 3 April 14 April 17 April 20 April 27 April 4 May

20/01/14-04/05/14: Wake-up and commissioning 05/05/14-02/07/14: NCD phase (‘Near Comet Drift’) 02/07/14-31/07/14: FAT phase (‘Far Approach Trajectory’) 01/08/14-16/08/14: CAT phase (‘Close Approach Trajectory’) 17/08/14-26/08/14: TGM phase (‘Transition to Global Mapping’) 27/08/14-23/09/14: GMP phase (‘Global Mapping Phase’) 24/09/14-25/10/14: COP phase (‘Close Observation Phase’) 26/10/14-11/11/14: Landing preparation and Landing

Rosetta 2014-2015

Separation velocity 0.05 - .5 m/s

at 3 km altitude

Rosetta 2014-2015

Following lander deployment - begin Escort phase of mission

Rosetta 2014-2015

• Navigation relies on navigation camera • ̃ 1.5 hour round trip communication delay • bound orbits only possible at a few 10s km

Rosetta will be the first mission to rendezvous with a

comet, the first mission to escort a comet, travelling at a relative walking pace.

In addition, it will deliver a lander, Philae, to the comet to get

ground truth from insitu measurements.

Will provide the most detailed study of a comet during its closest approach to the Sun

Conclusion

Arrival at comet Lander deployment Perihelion Nominal end-of-mission

Summer 2014 November 2014 August 2015 December 31, 2015

@ESA_Rosetta http://blogs.esa.int/rosetta/

Stay tuned...

END