Jakarta (ANTARA) – The James Webb space telescope belonging to the United States Aeronautics and Space Administration (NASA) on Monday approached its gravitational parking space in orbit around the sun nearly 1.6 million km from Earth.
The telescope was designed to give the world a new view of the early stages of the creation of the early universe.
The rocket booster will perform the final maneuver to correct direction at 19 GMT (Tuesday, 2 pm).
After that, Webb is expected to arrive at a stable orbital position between the earth and the sun known as Lagrange Point Two, or L2, one month after launch.
The thrusters will be activated by mission control technicians at the Space Telescope Science Institute in Baltimore.
The ground team will use radio signals to determine whether Webb was successfully “inserted” into orbit, said Eric Smith, NASA’s Webb program scientist.
From his vantage point in space, Webb will traverse a special path so that the telescope and the earth are always aligned as they revolve around the sun so as not to interfere with radio contact.
For comparison, Webb’s now 30-year-old predecessor, the Hubble telescope, orbits Earth from a distance of 547 km, circling the blue planet every 90 minutes.
The combination of the sun’s and earth’s pulls at L2 kept Webb in such a position that only a small amount of rocket thrust was needed to keep the telescope out of orbit.
The L2 position has been used by a number of satellites over the years because it allows “the least fuel consumption to stay in orbit”, Smith said.
The operations center has also started adjusting the direction of the Webb main mirror.
The mirror is composed of 18 hexagonal segments made of gold-plated beryllium metal measuring 6.5 meters, larger than the main Hubble mirror.
Its size and shape, designed to operate in the infrared spectrum, allow Webb to see through clouds of gas and dust, and to observe objects in the distance, allowing it to peer further into the “past” than Hubble or any other telescope.
These features are expected to bring about a revolution in astronomy, providing the first glimpses of infant galaxies 100 million years old after the Big Bang.
Big bang or Big Bang is the theoretical point from which the universe began about 13.8 billion years ago.
Webb’s instruments also make them ideal for looking for signs of life-sustaining atmospheres on a number of exoplanets – planets orbiting distant stars – and for observing other worlds closer to Earth, such as Mars and Saturn’s icy moon Titan.
Next step
It took several more months to prepare Webb for his debut.
Its main mirror segments – folded and loaded into the rocket’s cargo hold as it is carried into space – are stretched alongside other components for two weeks from its launch on December 25.
The segments were recently removed from the straps and slowly moved forward half an inch from the initial configuration, so that they could be stretched into one complete light-gathering plane.
The 18 segments must now be aligned so that the mirror has proper focus. The process will take three months.
During the alignment process, the ground team will begin activating the spectrographs, cameras and other instruments at the observatory, followed by a two-month instrument calibration process, Smith said.
If all goes well, Webb will be ready to start his observations in early summer, and send in preliminary pictures to check that the instruments are working properly.
But Smith said Webb’s most ambitious task, including plans to train his mirror to capture objects furthest from Earth, would take much longer for the world to see the images captured by the telescope.
The Webb Telescope is an international collaboration of space agencies in Europe and Canada led by NASA. Northrop Grumman Corp. is the prime contractor.
Source: Reuters
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