[ad_1]
MADRID, 13 Nov. (EUROPA PRESS) –
In 1966, NASA launched the Surveyor 2 mission to the moon. Now, your Centaur booster rocket has apparently returned to near-Earth space, captured by the gravity of our planet.
As reported by the space agency, This tiny object will remain as a temporary satellite for a few months before escaping back into solar orbit.
This celestial capture and release story begins with the detection of an unknown object by the NASA-funded Pan-STARRS1 reconnaissance telescope in Maui in September. Pan-STARRS astronomers noted that this object followed a slightly but clearly curved path in the sky, which is a sign of its proximity to Earth. The apparent curvature is caused by the observer’s rotation around the Earth’s axis as our planet rotates.
Assuming it is an asteroid orbiting the Sun, the object has received a standard designation from the Minor Planet Center in Cambridge, Massachusetts: 2020 SO. But scientists from NASA’s Center for Near Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Laboratory saw the object’s orbit and suspected it was not an ordinary asteroid.
Most asteroid orbits are more elongated and inclined than Earth’s orbit. But the 2020 SW orbit around the Sun was very similar to that of Earth: it was approximately the same distance, almost circular, and on an orbital plane that coincided almost exactly with that of our planet, which is very unusual for a natural asteroid.
As astronomers from Pan-STARRS and around the world made further observations of the 2020 SO, the data also began to reveal the degree to which the Sun’s radiation was changing the trajectory of the 2020 SO. an indication that it may not be an asteroid after all.
The pressure exerted by sunlight is small but continuous and has a greater effect on a hollow object than on a solid one. A spent rocket is essentially a hollow tube, and is therefore a low-density object with a large surface area. Therefore, it will be pushed by the pressure of solar radiation more than a high-density solid rock mass, just as an empty can will be blown by the wind more than a pebble.
“The pressure of solar radiation is a non-gravitational force caused by photons of light emitted by the Sun hitting a natural or artificial object,” said Davide Farnocchia, a navigation engineer at JPL, who analyzed the 2020 SO trajectory for CNEOS . “The resulting acceleration on the object depends on the so-called area-to-mass ratio, which is higher for small, light and low-density objects.”
With the analysis of more than 170 detailed measurements of the 2020 SO position over the past three months, including observations from the NASA-funded Catalina Sky Survey in Arizona and the ESA Optical Earth Station (European Space Agency) in Tenerife, the pressure impact of solar radiation became evident and confirmed the low-density nature of 2020 SO. The next step was to figure out where the supposed booster rocket could have come from.
The Surveyor 2 lunar lander was launched to the moon on September 20, 1966 on an Atlas-Centaur rocket. The mission was designed to examine the lunar surface prior to the Apollo missions which resulted in the first manned lunar landing in 1969. Shortly after takeoff, the Surveyor 2 separated from the Centaur upper stage thruster as intended. But control of the spacecraft was lost the next day when one of its thrusters failed to fire, causing it to spin. The spacecraft crashed into the moon just southeast of the Copernicus crater on September 23, 1966. Meanwhile, the depleted upper stage of the Centaur rocket passed in front of the Moon and disappeared into an unknown orbit around the Sun.
Suspecting that the 2020 SO was a remnant of an ancient lunar mission, CNEOS director Paul Chodas “turned the clock back” and orbited the object to determine where it had been in the past. Chodas found that the 2020 SO had gotten a little closer to Earth several times over the decades, but the 2020 SO approach in late 1966, according to their analysis, would have been close enough to originated on Earth.
“One of the possible paths for 2020 SO brought the object very close to the Earth and the Moon in late September 1966,” Chodas said. “It was like a eureka moment when a quick review of the lunar mission launch dates showed a match to the Surveyor 2 mission.”
Now, in 2020, the Centaur appears to have returned to Earth for a brief visit. On November 8, 2020, SO slowly slipped into the sphere of Earth’s gravitational domain, a region called the Hill sphere that extends approximately 1.5 million kilometers from our planet. It is there that 2020 SO will remain for about four months before it escapes again into a new orbit around the Sun in March 2021.
Before leaving, 2020 SO will do two major tours around our planet, with its closest approach on December 1st. During this time, astronomers will take a closer look and study its composition using spectroscopy to confirm whether 2020 SO is indeed an early space age artifact.
Source link
