NASA has launched an unprecedented rescue mission to raise the orbit of the Neil Gehrels Swift Observatory, which was threatened with falling to Earth due to its orbit becoming lower than expected.

The Link robotic rescue vehicle, equipped with three robotic arms, launched from the Marshall Islands today and is expected to take about a month to reach the telescope, which has been orbiting Earth since 2004.

Swift's altitude decreased due to increased solar activity, which heated and expanded the Earth's upper atmosphere, causing an increase in air resistance and gradually pulling the telescope towards Earth. Without the rescue mission, it was expected to burn up upon re-entry by October.

NASA has invested around $30 million “or approximately €27 million” with Katalyst Space Technologies to carry out the mission, which aims to grasp the telescope and raise its orbit to a safer altitude, so that it can continue monitoring some of the most violent cosmic phenomena, such as gamma-ray bursts and star explosions.

Link reached orbit after being launched by Northrop Grumman's Pegasus XL rocket on its final flight, where it was launched from beneath an altered plane over the Pacific Ocean.

Swift is currently orbiting at an altitude of 360 kilometers above Earth's surface and needs to raise its orbit by another 240 kilometers to reach a safe altitude. Link's engines will work gradually to avoid exposing the old telescope to any vibrations that could affect its safety.

If the mission is successful, it is expected that the observatory will resume its scientific operations by September. However, observations have been temporarily suspended to reduce altitude loss during the rescue operation.