NASA's James Webb Space Telescope, designed to give the world an unprecedented glimpse of the universe's early baby galaxies, arrived on Monday at its gravitational stop in orbit around the sun, nearly 1 million miles from Earth. earth.
NASA officials said Weber arrived at its destination under the last 5-minute heading correction thrust of its airborne rocket, known as the second Helio-Di Lagrange point, or L2, a month after launch.
The thrusters were activated by mission control engineers at the Baltimore Space Telescope Science Institute, and radio signals confirmed that Weber had successfully "inserted" into the desired orbital ring around L2.
From there, Weber will follow a special "halo" path to keep it in tune with Earth but away from its shadow as planets and telescopes orbit the sun in tandem. As a result, the defined L2 orbit within the larger solar orbit allows for uninterrupted radio contact while bathing Weber's solar array in uninterrupted sunlight.
By comparison, Weber's 30-year-old predecessor, the Hubble Space Telescope, orbits the Earth from 340 miles (547 kilometers) away, moving in and out of the Shadow of the Earth every 90 minutes.
The combined pull of the Sun and Earth at L2 — a point of near-gravitational stability first deduced by the 18th-century mathematician Joseph Louis Legrange — will minimize the telescope's drift in space.
But the ground team needs to briefly turn on Webb's thrusters again about every three weeks to keep it up and running, Keith Parrish, observatory commissioning manager from NASA's Goddard Space Flight Center in Maryland, told reporters Monday.
Mission engineers are next preparing to fine-tune the telescope's main mirror— an array of 18 hexagonal gold-plated beryllium metal segments that are 21 feet 4 inches (6.5 meters) wide, much larger than Hubble's main mirror.
Its size and design — which operates primarily in the infrared spectrum — will allow Weber to look at objects at greater distances through clouds of gas and dust, and thus farther than Hubble or any other telescope.
These features are expected to spark an astronomical revolution, giving people the first glimpse of newborn galaxies dating back just 100 million years after the Big Bang, a theoretical flashpoint estimated to be the expansion of the known universe 13.8 billion years ago.
Weber's instrument is also ideal for looking around dozens of newly recorded exoplanets (objects orbiting distant stars) for signs of potentially life-sustaining atmospheres, as well as observing worlds closer to Earth, such as Titan, the icy moons of Mars and Saturn.
It will take a few more months of work to prepare for the telescope's astronomical debut.
Within two weeks of Weber's December 12 launch, the 18 sections of its main mirror had been folded together to fit into the cargo hold of the rocket that sent the telescope into space and unfolded along with other structural components. 25. Read more
These parts have recently separated from the fasteners and moved away from their original emitting positions. They must now be precisely aligned — within one-ten-thousandth of the thickness of a human hair — to form a single, complete light-collecting surface.
The ground team will also begin activating Weber's various imaging and spectroscopic instruments for use in the three-month mirror calibration. It will then take two months to calibrate the instrument yourself.
The specular calibration will first aim the telescope at a fairly ordinary isolated star, called HD-84406, located in the constellation Ursa Major or the "Big Dipper," but too faint to be visible from Earth with the naked eye.
Lee Feinberg, Weber's optical telescope component manager at Goddard, told a NASA conference call on Monday that engineers would gradually tweak Weber's segments to "stack" the 18 independent reflections of the star into a single focused image.
Calibration is expected to begin next week, when the telescope's infrared design makes it super sensitive to heat, cooling enough in space to function properly — temperatures below zero degrees Fahrenheit (-240 degrees Celsius) by about 400 degrees.
If all goes well, Weber should be ready to start scientific observations in the summer.
Sometime in June, NASA is expected to release its "early published observations," a set of "hottest" initial images used to show how webb's instruments functioned properly during its commissioning phase.
Weber's most ambitious work, including plans to train its mirrors on objects furthest from Earth, will take longer to carry out.
The telescope is an international cooperation project led by NASA, in collaboration with space agencies in Europe and Canada. Northrop Grumman Corporation (NOC. N) is the main contractor.