ST. GEORGE — In November, the Kepler telescope ended all of its communication with Earth, but the first batch of data from a brand new telescope was received by NASA scientists just three days ago.
A set of “goodnight” commands finalized the Kepler spacecraft’s mission, officially sending the satellite into retirement, but as one mission ends, another begins. With the launch of the Transiting Exoplanet Survey Satellite — or TESS — comes the next step in the search for planets outside of the solar system, including ones that could potentially support life.
Launched April 18 on a Falcon 9 rocket, TESS is designed to survey the sky over the course of its two-year mission by breaking it up into 26 different sectors. The satellite is programmed to stare at each sector for at least 27 days using its powerful cameras.
The first set of images from the mission reached NASA scientists Thursday, representing data collected by TESS from July 25 through the end of September. The images have been made public and are included in this report.
While Kepler’s discoveries were a game-changer for NASA and helped put to rest the theory that Earth to Neptune-sized planets were uncommon, the TESS Mission is designed to survey an area 400 times larger than Kepler was capable of. TESS is capable of surveying more than 85 percent of the sky and studying stars that are 30-100 times brighter.
Like Kepler, TESS is able to observe planets in transit — periods when a planet’s star dims as it passes over it in orbit. Unlike Kepler, TESS has the advantage of an unobstructed view thanks to its unique elliptical high Earth orbit, according to NASA.
Many satellites used for communication and imaging circle the earth in a low-earth orbit, or roughly 150-350 miles above the surface of the Earth (for a point of reference, the International Space Station is approximately 200 miles up). However, most satellites used for communication are in “high-earth” synchronous orbits, approximately 22,300 miles in space. At that distance, it takes a satellite in orbit around the equator 24 hours to complete an orbit – the same as it takes the Earth to complete a full turn. Thus the satellite appears in a fixed point in the sky, and consequently, small rooftop antennas are typically fixed in place.
However, since satellites positioned in orbit above the equator can’t “see” the poles, low-altitude satellites are deployed to cover these “polar orbits.” (See Ed. note)
Kepler’s remarkable legacy
Even with a much more powerful telescope replacing it, the unbelievably successful Kepler mission revealed more than 4,500 exoplanets
during its nine years of transmission starting in 2009. NASA scientists are still mining the mass of data it sent back for new discoveries.
Typically, numerous instruments are built into a spacecraft or satellite depending on the mission, but with Kepler, NASA put all of its eggs in just one basket — the photometer, a 3-foot telescope that illuminated a 95 megapixel digital camera the size of a cookie sheet, the largest camera ever launched into space at the time.
In fact, Kepler’s telescope was so powerful it could detect a person in a small town turning off a porch light at night.
The photometer locked its eyes on 150,000 individual stars during the course of the nine-year mission, detecting the presence of planets by measuring subtle changes in light caused by the planet passing in front if its star.
The Kepler spacecraft launched with a little more than 3 gallons of fuel on board for what was expected to be a three and a half-year mission. The hearty spacecraft endured many setbacks and near-misses as it orbited around the sun, from mechanical failures to being blasted by cosmic rays.
Even so, Kepler carried on for more than nine years until it finally ran out of fuel at the end of October.
The Kepler now drifts abandoned and locked in eternal silence more than 94 million miles from the earth in a wide orbit around the sun and will eventually make its way back toward home by 2069.
Ed. note: An earlier version of this story misidentified the varying levels of orbits and satellite travel.
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