Breaking news! The James Webb Telescope can reach L2 in less than 3 hours! See here how

Credit: NASA
Credit: NASA

Breaking news! The James Webb Telescope is so close to L2 that it can reach that point in less than 3 hours if it maintains its speed. According to NASA, Webb is at approx. 2000 km away from L2. Its speed is 0.2020 km / s. According to the formula speed = distance / time, this means that time = distance / speed. Substituting numerically, we will have 2000km / 0.2020km / s = ~ 9900 s (seconds). It turns out that 9900 s = ~ 165 minutes, and 165 minutes = ~ 2.75 hours, which means less than 3 hours to L2. 

But Webb can change its speed a little, but we should expect it to reach L2 in a maximum of 3 and a half hours in case the speed changes suddenly, but the chances are small that it will change a lot. Webb may change speed a little bit due to the latest burn correction prepared by NASA today, January 24, 2022. According to NASA: "On Monday, Jan. 24, engineers plan to instruct NASA's James Webb Space Telescope to complete a final correction burn that will place it into its desired orbit, nearly 1 million miles away from Earth at what is called the second Sun-Earth Lagrange point, or "L2" for short." 

(The burn correction will take place before Webb reaches L2.)

The James Webb telescope has traveled about 1.5 million kilometers so far (a little more), which is about 1 million miles away. 

More explanations from a NASA expert about Webb's journey and some details before the historic moment (reaching L2): 

"Think about throwing a ball straight up in the air, as hard as you can; it starts out very fast but slows down as gravity pulls it back towards Earth, eventually stopping at its peak and then returning to the ground. Similar to your arm giving the ball energy to go up a few meters from the Earth's surface, the Ariane 5 rocket gave Webb energy to go the great distance of 1.1 million kilometers, but not quite enough energy to escape Earth's gravity. Just like the ball, Webb is slowing down, and, if we allowed it, would eventually stop and fall back toward Earth. Unlike the ball, Webb wouldn't return to Earth's surface but would be in an extremely elliptical orbit, with a perigee altitude of 300 kilometers and an apogee altitude of 1,300,000 kilometers. Utilizing thrust every three weeks or so from small rocket engines aboard Webb will keep it orbiting L2, looping around it in a halo orbit once every six months. "

"So, why did the Ariane not give Webb more energy and why did Webb need course correction? If the Ariane had given Webb even a little bit too much energy than needed to get it to L2, it would be going too fast when it got there and would overshoot its desired science orbit. Webb would have to do a significant braking maneuver by thrusting toward the Sun to slow down. Not only would that big burn cost a lot of propellant, it would be impossible because it would require Webb to turn 180 degrees in order to thrust toward the Sun, which would have exposed its telescope optics and instruments directly to the Sun, thus overheating their structures and literally melting the glue that holds them together. Mounting thrusters on the telescope as a way to direct braking thrust was infeasible for a number of reasons and was never a design option."

"Therefore, Webb requested just enough energy from the Ariane rocket to ensure that we would never have to do a retro burn, but would always require a burn from the observatory to precisely make up the difference and place it in the desired orbit. The Ariane 5 targeted Webb so accurately that our first and most critical burn was smaller than we had to plan and design for, leaving more fuel for an extended mission!"

-Karen Richon, Webb Flight Dynamics lead engineer, NASA's Goddard Space Flight Center

Article by: Andacs Robert Eugen, on 24 January 2022, at 08:28 am Los Angeles time

You can write your news here:

Bailey Universe contact:

Be the first to read what's new from space!