ESA Rosetta mission: Philae lander - the sound of a Comet Touchdown

Image credit: ESA/ATG medialab – Audio file credit: ESA /Rosetta /Philae /SESAME /DLR

Sensors in the feet of Rosetta’s lander Philae have recorded the sound of touchdown as it first came into contact with Comet 67P/Churyumov-Gerasimenko. 

The instrument, SESAME-CASSE, was turned on during the descent and clearly registered the first touchdown as Philae came into contact with the comet, in the form of vibrations detected in the soles of the lander’s feet.

Focus on SESAME. Sensors are located in the three feet as well as in the units of the APXS (centre) and MUPUS-Pen (to the upper right of centre) instruments. Credits: ESA/ATG medialab

SESAME is the lander’s Surface Electrical Sounding and Acoustic Monitoring Experiment, and comprises three suites of instruments:

• CASSE – the Comet Acoustic Surface Sounding Experiment, which allows mechanical parameters of the surface to be deduced, along with details of the structure of the subsurface;
• DIM – the Dust Impact Monitor, which measures properties of impacting comet grains;
• PP – the Permittivity Probe, which determines one of the key electrical properties of the material beneath Philae, which is linked to the water ice content of the surface.

Klaus Seidensticker from the DLR Institute of Planetary Research says: “Our data record the first touchdown and show that Philae’s feet first penetrated a soft surface layer – possibly a dust layer – several centimetres thick until they hit a hard surface – probably a sintered ice-dust layer – a few milliseconds later.”

Expedition 39 Touchdown! Space Station Crew Return to Terra Firma

Expedition 39 astronauts Koichi Wakata, Mikhail Tyurin and Rick Mastracchio (left to right) rest after landing in a Soyuz capsule on May 13, 2014.

Credit: NASA TV

Three crew members of the International Space Station have returned safely to Earth, ending their six-month orbital mission.

A Russian Soyuz capsule carrying NASA astronaut Rick Mastracchio, Japanese astronaut Koichi Wakata and cosmonaut Mikhail Tyurin landed on the steppes of Kazakhstan at 9:58 p.m. EDT Tuesday night (May 13; 7:58 a.m. local time on Wednesday, May 14).

The Soyuz undocked from the space station 3 1/2 hours earlier while the two vehicles were above Mongolia, marking the end of Expedition 39 and the beginning of Expedition 40 aboard the orbiting lab.

"What an exciting time we shared in this increment," Expedition 39 Commander Wakata said Monday (May 12) as he handed the station's reins over to NASA astronaut Steve Swanson.

"Congratulations, and best wishes to the crew of Expedition 40 for a successful mission."

Wakata, Mastracchio and Tyurin enjoyed an eventful and historic stint in orbit after arriving at the space station on Nov. 7, 2013.

For example, Wakata became the first Japanese person ever to command the station when he took charge of Expedition 39 on March 10.

Just four days later, Wakata and Mastracchio participated in "Live from Space," a two-hour TV event hosted by Soledad O'Brien that aired on National Geographic Channel, as well as Channel 4 in the United Kingdom.

"Live from Space" gave viewers in more than 140 countries an idea of what it's like to live and work on the orbiting lab, with Wakata giving a guided tour of the $100-billion complex.

Japanese astronaut Koichi Wakata, commander of the International Space Station's Expedition 39 mission, is helped out of the Soyuz capsule.

ISS Expedition 36 Crew touchdown safely

Russian cosmonaut Pavel Vinogradov (right) waves to cameras alongside NASA astronaut Chris Cassidy after a successful Soyuz landing in Kazakhstan on Sept. 10, 2013 EDT (Sept. 11 local time), ending a five-month mission to the International Space Station. Crewmate Alexander Misurkin is not pictured.

Credit: NASA TV

A Soyuz capsule carrying three astronauts has touched down on Earth after undocking from the International Space Station after 166 days in space.

Nasa's Chris Cassidy and Russians Pavel Vinogradov and Alexander Misurkin landed safely in Kazakhstan, where they launched on March 29.

Live Nasa footage showed the three men emerging from the capsule and onto the sunny Kazakh steppe, where they will first be put into reclining chairs that will help them readjust to the Earth's gravity.

The Soyuz is the only means for international astronauts to reach the orbiting laboratory since the decommissioning of the US shuttle fleet in 2011.

Before leaving the space station, Cassidy told reporters he would be sad to leave the orbiting lab behind, but at the same time he was excited to return home and see his wife and three children again.

In addition to rejoining his family, a "gooey, fresh-baked chocolate chip cookie ranks right on the top of my list," stated Cassidy.

The Expedition 36 crew of the International Space Station waves farewell before undocking a Soyuz space capsule to return to Earth on Sept. 10, 2013. 

They are Russian cosmonauts Alexander Misurkin (right), Pavel Vinogradov (left) and NASA astronaut Chris Cassidy. 

Credit: NASA