After a detailed analysis of where the James Webb Space Telescope is now (December 29, 2021) and how it got there, NASA decided that the observatory must have enough fuel to operate in space for well over 10 years.
The Webb mission was designed to last for a minimum of 5-1 / 2 years, and mission engineers and scientists had hoped for about 10 years.
The announcement this week is “well over 10 years” due to two factors: the accuracy of the Ariane 5 launch on December 25, which experts say exceeds the requirements needed to get Webb on the right track.
And now, due to how accurate the JWST’s trajectory was, the first two corrective maneuvers mid-course required significantly less fuel than expected.
The first fix to the course was a 65 minute burn, which occurred approximately 12.5 hours after launch. While 65 minutes sounds like a long time, it could require burning for up to 3 hours.
This first burn set the observatory on an even more accurate track and increased the observatory’s speed by about 45 miles per hour (20 meters / sec). A second shorter corrective maneuver on December 27 added about 6.3 mph (2.8 m / s) to the speed.
The JWST’s lifespan is limited by the amount of fuel used to reach L2 and maintain its orbit, and the possibility that Webb’s components will decompose over time in the harsh conditions of space.
The exact trajectory that the observatory is currently following means more fuel to maintain orbit and control momentum in the future, which means longer service life.
Which also means more science!
Illustration showing Lagrange point 2. (NASA)
“The largest and most important Intermediate Correction (MCC), designated MCC-1a, was already successfully completed as planned 12.5 hours after launch,” wrote Randy Kimble, Research Assistant for the Integration, Testing and Commissioning Project at JWST at NASA. Goddard, in a blog post detailing course correction maneuvers.
“This time was chosen because the earlier the course correction is made, the less fuel will be needed.”
What are Lagrange points and why is the JWST going there?
I’ve made this digestible breakdown: I hope it will be helpful to someone here on Twitter! 1/6# Physics # Space exploration pic.twitter.com/MTpCxnH62T
– Marie-Liis with a double “i” (@bymarieliis) December 27, 2021
Another big news from Webb is that the first tennis-court-sized sunscreens have been successfully deployed.
On December 28, the bow and stern anti-sun trays were deployed. The deployable tower assembly was also expanded – a six-hour operation controlled remotely from the Operations Center. This tower creates space between the spacecraft and the telescope, giving the sunscreen space to deploy. When everything is deployed, this space will also help keep the telescope cold.
The next steps are to remove the sun visors, lengthen the middle rods, and finally tension the five Kapton layers of the sun visor itself.
Animation of JWST revealing its sun visors. (NASA)
This will happen over the next few days. NASA says that because sun visor deployment is one of the most challenging spacecraft deployment options ever undertaken by NASA teams, the mission’s task force has brought flexibility into the planned timeline so that the schedule and even the sequence of next steps may change in the near future. days.
NASA also noted that more details are being added to the Where Is Webb website, where all kinds of information about the observatory can be found. You can now track the temperature of the spacecraft.
Webb will actually have two different temperatures due to the fact that it is warm on one side and cold on the other. The sunscreen will always be facing the Sun to block heat and light, as Webb’s mirrors must remain very cold in order to observe faint heat signals in the universe.
You are hot and you are cold … ?#NASAWebb divided into “hot side” and “cold side” by its sunscreen. The sunscreen will always be facing the Sun to block heat and light, as Webb’s mirrors must remain very cold to observe faint heat signals in the universe! pic.twitter.com/GciNPo04nr
– NASA Webb Telescope (@NASAWebb) December 29, 2021
On the other hand, in parts of Webb, temperatures reach 85 degrees Celsius or 185 degrees Fahrenheit. On the cold side of Webb it will be around -233 degrees Celsius or -388 degrees Fahrenheit.
NASA said temperatures will continue to change as Webb unfolds and then cools down to operating temperatures over the next months.
This article was originally published by Universe Today. Read the original article.
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