Herschel and Planck Missions to Study Cosmos Share Ride to Space
“The missions are quite different, but they’ll hitch a ride to space together,” said
Israelsson is with NASA’s Jet Propulsion Laboratory, or JPL, in
The Herschel observatory has the unique ability to peek into the dustiest and earliest stages of planet, star and galaxy growth. The spacecraft’s astronomy mirror — about 11.5 feet (3.5 meters) in diameter — is the largest ever launched into space. The mirror will collect longer-wavelength light in the infrared and submillimeter range — light never before investigated by an astronomy mission.
“We haven’t had ready access to the wavelengths between infrared and microwaves before, in part because Earth’s atmosphere blocks them from reaching the ground,” said
The coolest objects in the universe, such as dusty, developing stars and galaxies, appear as dark blobs when viewed with visible-light telescopes. As a result, astronomers do not know what is happening inside them. However, at longer wavelengths in the far-infrared and submillimeter range, cool objects shine brightly. Herschel will detect light from objects as cold as -263 degrees Celsius, or 10 Kelvin, which is 10 degrees above the coldest temperature theoretically attainable. Onboard liquid helium, which is expected to last more than three and a half years, will chill one of Herschel’s detectors to a frosty 0.3 Kelvin.
Planck will answer fundamental questions about how the universe came to be and how it will change in the future. It will look back in time to just 400,000 years after our universe exploded into existence nearly 14 billion years ago in the event known as the Big Bang. The mission will spend at least 15 months making the most precise measurements yet of light at microwave wavelengths across our entire sky, including what is called the cosmic microwave background. This light is from the primordial soup of particles that eventually evolved to become our modern-day universe. The light has traveled about 14 billion years to reach us, and, in that time, has cooled and stretched to longer wavelengths because space is expanding.
“The cosmic microwave background shows us the universe directly at age 400,000 years, not the movie, not the historical novel, but the original photons,” said
Planck will be cold too. One of its instruments will be cooled to just 0.1 Kelvin. Innovative “cryocooler” technology, developed in part by JPL, will chill the instruments.
Shortly after launch, Planck and Herschel will separate from the rocket and follow different trajectories to the second Lagrangian point of our solar system, a point in space 930,000 miles (1.5 million kilometers) from Earth.
Herschel and Planck are both ESA missions with important participation from NASA. NASA’s Herschel Project Office and Planck Project Office are both based at JPL. A consortium of European-led institutes provided science instruments for Herschel. JPL contributed mission-enabling technology for two of Herschel’s three science instruments and both of Planck’s science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the
More information about the Herschel mission is available online at:
More information about the Planck mission is available online at: