Making History: Rosetta Catches its Comet on November 12!
It’s an exciting time for solar system scientists, as on Wednesday, November 12, 2014, the European Space Agency‘s Rosetta mission will become the first spacecraft in human history to land on a comet — one of the primitive, icy bodies that are left overs from our solar system’s formation about 4.6 billion years ago.
Rosetta is scheduled to touchdown on comet 67P/Churyumov-Gerasimenko (“67P/C-G” for short) at 10:35 AM Eastern Time, with a signal confirming the landing reaching Earth at 11:03 AM. A live-stream of the landing will be available as a webcast, and a special free public program will be held in our Daily Planet Theater, including the live stream and presentation by Dr. Rachel Smith, Director of the Astronomy & Astrophysics Research Lab at the Museum.
Rosetta first made history on August 4, 2014, when it awoke from its ten-year hibernation while en route to comet 67P/C-G to became the first spacecraft to lock in synchronous orbit with a comet. When its robot lander, called Philae, will deploy next week, Rosetta will begin unprecedented detailed studies of the comet’s nucleus — the big chunk of ice and rock that comprises much of the mass, and coma — the material that spews off the surface when it begins to sublime during its approach toward a few hundred million miles of the Sun. This spewed material creates the images that we are perhaps most familiar with when we think of comets coming close to Earth.
Comets are thought to be one of the most primitive groups of solar system bodies, vestiges of our early formation that hold clues to our chemical origins. Like the asteroids we see more frequently (and pieces of which we find on Earth as meteorites), comets impacted Earth and other planets and moons in the past. One of the most burning questions that Rosetta will help answer is how Earth obtained its oceans; many scientists think that comets could have seeded our planet’s oceans through impacts during our early history several billion years ago. In 2011, spectroscopic measurements from the Herschel Space Observatory showed that water from comet Hartley 2 was chemically very similar to Earth’s water; Rosetta will analyze the chemistry of water in Comet 67P/C-G in even greater detail to thoroughly investigate the comet origin theory.
Further, in 2006, the mission Stardust passed through the tail of comet Wild 2, collecting tiny particles that were found to be rich in organic matter. These particles support the theory that, like our oceans, organic molecules, including the building blocks of living organisms, could have been seeded by cometary impacts. One of Rosetta’s key scientific missions will be to study a detailed inventory of Comet 67P/C-G’s chemical, mineralogical, and isotopic composition in order to advance our understanding of organics on comets and how they may relate to the origin of life on Earth.
Comet 67P/C-G is about 3 AU from the Sun, or 450 million km, about 3 times the distance from the Earth to the Sun. After landing its robot onto the surface, Rosetta will travel with 67P/C-G as it travels to the inner solar system and is heated by the Sun, enabling first-ever studies of detailed changes to a comet occurring during its approach to perihelion (a body’s closest distance to the Sun).
Earlier this year, Rosetta’s cameras sent images of the 67P/C-G’s surface, showing its dual-lobed surface in startling, first-ever detail. A few of these spectacular images are shown below; you can find a wider selection of images from Rosetta on the JPL website.
Next week’s soft landing will be scientifically groundbreaking, and one of the most exciting times for planetary science! Join us on Wednesday in the Daily Planet theater to witness this live landing, and hear more about Rosetta’s science and technological breakthroughs.
Solar system research at the Museum: I am an observational astronomer studying solar system origins from a different vantage point: outside of our solar system. I use the largest ground-based optical/infrared telescopes to study the chemistry of forming planetary systems in our Galaxy, and compare these data to the oldest material from our solar system, including meteorites, the Sun, and hopefully soon, Comet 67P/C-G. Visit my Museum webpage and other research blogs as well as the astrophysics displays in the Astronomy & Astrophysics Research Lab and the Museum’s meteorite collection to learn more!