4.5-bil­lion-year-old Ice on Comet ‘Fluffi­er than Cap­puc­ci­no Froth’

Af­ter sev­en hours of freefall, Philae touched the Ag­ilkia land­ing site (top left out­side the im­age) at walk­ing pace as planned. How­ev­er, Phi­lae could not an­chor it­self be­cause the an­chor har­poons pro­vid­ed for this pur­pose did not ac­ti­vate. Due to the low grav­i­ty, Phi­lae bounced off the sur­face, rose to a height of more than one kilo­me­tre, col­lid­ed with a cliff edge while falling, touched the comet’s sur­face a sec­ond time (TD2) and fi­nal­ly came to a halt af­ter two hours (TD3). The lo­ca­tion of TD2 was un­known un­til re­cent­ly and could on­ly now be re­con­struct­ed. Phi­lae was lo­cat­ed in a place with suf­fi­cient sun­light to pro­duce enough en­er­gy to run its ten ex­per­i­ments for ap­prox­i­mate­ly 60 hours. (Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)
  • Reconstruction of second surface contact by Rosetta’s Philae lander during unplanned ‘hopping’ in November 2014 before its final ‘touchdown’.
  • The probe, rotating like a windmill, scraped a furrow in a highly porous, dark rocky area made of ice and dust on comet 67P, exposing 4.5-billion-year-old ice.
  • The ice has very weak internal cohesion and a consistency that is fluffier than cappuccino froth.

COLOGNE, Germany (DLR PR) — After years of detective work, scientists working on the European Space Agency (ESA) Rosetta mission have now been able to locate where the Philae lander made its second and penultimate contact with the surface of Comet 67P/Churyumov-Gerasimenko on 12 November 2014, before finally coming to a halt 30 metres away. This landing was monitored from the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) Philae Control Center.

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Ammonium Salts Found on Rosetta’s Comet

Scientists have detected ammonium salts on the surface of Comet 67P/Churyumov-Gerasimenko (shown in this image on the right). [Credit: O. Poch, IPAG, UGA/CNES/CNRS (left); ESA/Rosetta/NavCam – CC BY-SA IGO 3.0 (right)]

GRENOBLE, France (ESA PR) — Scientists have detected ammonium salts on the surface of Comet 67P/Churyumov-Gerasimenko by analysing data collected by the Visible, Infrared and Thermal Imaging Spectrometer (VIRTIS) on ESA’s Rosetta mission between August 2014 and May 2015.

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Comet’s Collapsing Cliffs and Bouncing Boulders

An example of a boulder having moved across the surface of Comet 67P/Churyumov-Gerasimenko’s surface, captured in Rosetta’s OSIRIS imagery. [Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA (CC BY-SA 4.0)]

PARIS (ESA PR) — Scientists analysing the treasure trove of images taken by ESA’s Rosetta mission have turned up more evidence for curious bouncing boulders and dramatic cliff collapses.

Rosetta operated at Comet 67P/Churyumov-Gerasimenko between August 2014 and September 2016, collecting data on the comet’s dust, gas and plasma environment, its surface characteristics and its interior structure.

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Rosetta’s Comet Sculpted by Stress

Single frame enhanced NavCam image taken on 27 March 2016, when Rosetta was 329 km from the nucleus of Comet 67P/Churyumov-Gerasimenko. The scale is 28 m/pixel and the image measures 28.7 km across. (Credit:  ESA/Rosetta/NavCam)

18 February 2019

MARSEILLE, France (ESA PR) — Feeling stressed? You’re not alone. ESA’s Rosetta mission has revealed that geological stress arising from the shape of Comet 67P/Churyumov–Gerasimenko has been a key process in sculpting the comet’s surface and interior following its formation.

Small, icy comets with two distinct lobes seem to be commonplace in the Solar System, with one possible mode of formation a slow collision of two primordial objects in the early stages of formation some 4.5 billion years ago. A new study using data collected by Rosetta during its two years at Comet 67P/C-G has illuminated the mechanisms that contributed to shaping the comet over the following billions of years.

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Cosmic Detective Work: Why We Care About Space Rocks

This artist’s concept depicts the spacecraft of NASA’s Psyche mission near the mission’s target, the metal asteroid Psyche. (Credits: NASA/JPL-Caltech/Arizona State Univ./Space Systems Loral/Peter Rubin)

By Elizabeth Landau
NASA

The entire history of human existence is a tiny blip in our solar system’s 4.5-billion-year history. No one was around to see planets forming and undergoing dramatic changes before settling in their present configuration. In order to understand what came before us — before life on Earth and before Earth itself — scientists need to hunt for clues to that mysterious distant past.

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Rosetta Finds Missing Philae Comet Lander

Rosetta’s lander Philae has been identified in OSIRIS narrow-angle camera images taken on 2 September 2016 from a distance of 2.7 km. The image scale is about 5 cm/pixel. (Credit: Main image and lander inset: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA; context: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0)
Rosetta’s lander Philae has been identified in OSIRIS narrow-angle camera images taken on 2 September 2016 from a distance of 2.7 km. The image scale is about 5 cm/pixel. (Credit: Main image and lander inset: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA; context: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0)

PARIS (ESA PR) — Less than a month before the end of the mission, Rosetta’s high-resolution camera has revealed the Philae lander wedged into a dark crack on Comet 67P/Churyumov–Gerasimenko.

The images were taken on 2 September by the OSIRIS narrow-angle camera as the orbiter came within 2.7 km of the surface and clearly show the main body of the lander, along with two of its three legs.

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J Marks the Spot for Rosetta’s Philae Comet Lander

Philae’s primary landing site. (Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)
Philae’s primary landing site. (Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

PARIS (ESA PR) — Rosetta’s lander Philae will target Site J, an intriguing region on Comet 67P/Churyumov–Gerasimenko that offers unique scientific potential, with hints of activity nearby, and minimum risk to the lander compared to the other candidate sites.

Site J is on the ‘head’ of the comet, an irregular shaped world that is just over 4 km across at its widest point. The decision to select Site J as the primary site was unanimous. The backup, Site C, is located on the ‘body’ of the comet.

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Rosetta Landing Sites Narrowed to 5

Philae candidate landing sites. (Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)
Philae candidate landing sites. (Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

PARIS, 25 August 2014 (ESA PR) — Using detailed information collected by ESA’s Rosetta spacecraft during its first two weeks at Comet 67P/Churyumov-Gerasimenko, five locations have been identified as candidate sites to set down the Philae lander in November – the first time a landing on a comet has ever been attempted.

Before arrival, Comet 67P/Churyumov-Gerasimenko had never been seen close up and so the race to find a suitable landing site for the 100 kg lander could only begin when Rosetta rendezvoused with the comet on 6 August.

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