The Earth 2 satellite was launched in 1995 and was used for remote sensing purposes (European Space Agency)
In July 2022, the United States of America occupied the world with the “Long March 5B” rocket that China launched carrying parts of the Chinese “Tiangong” space station, without Beijing following procedures that would help recover the debris of the launch rocket, which is what... The world then called it the “lost Chinese missile,” and fears were raised that its debris would fall in a populated area.
While the world will be on a date today, Wednesday, with the fall of the European satellite “Earth 2” lost in space in a place whose location is not yet known, the event does not raise the same uproar that the Chinese missile raises for three reasons, which experts talk about in exclusive statements with “Al Jazeera Net.” ".
European moon
The European Earth 2 satellite was launched on April 21, 1995, and was used for remote sensing purposes. It remained operational until July 4, 2011, when its lifespan ended. Then, in July and August 2011, the European Space Agency used its remaining fuel to perform 66 redirections to lower its orbit from an altitude of 785 km to 573 km, in order to reduce the chances of collision with other satellites.
The Australian commercial imaging company Hue Robotics was able to take pictures of it on February 14, when it began heading towards the Earth’s atmosphere, and subsequent estimates by the European Space Agency indicated that it would fall today, Wednesday (February 21), at 15:19 GMT. There is a possibility of error of plus or minus 19 hours.
The journey of the European Earth 2 satellite from launch to the expected end on February 21, 2024 (European Space Agency)
Pre-release guidelines
Because the Earth 2 satellite was launched 29 years ago, the requirements for space debris recovery approved by the United Nations General Assembly had not yet been established, which is different from the Chinese case. Therefore, the United States found a justification to raise the issue, says Rasha Ghoneim, head of the Space Research Laboratory at the National Institute for Astronomical and Geophysical Research in Egypt, in a telephone interview with Al Jazeera Net.
The United Nations Committee on the Peaceful Uses of Outer Space (COPOS) prepared a set of guidelines for space debris mitigation that were approved by the United Nations General Assembly in 2007, with the aim of addressing the problem of space debris accumulation in Earth's orbit.
These guidelines recommend that “at the end of a spacecraft's operational life, safe disposal procedures should be followed to reduce the risk of additional debris formation, and this may include deorbiting the spacecraft to ensure its reentry into the Earth's atmosphere within a specified time frame.”
Rasha Ghoneim says: “The United States of America accused China at the time of not observing these guidelines, and accused it of the uncontrolled launch of the Long March 5B missile, while there is no logical justification for provoking the same crisis with the European satellite, because it relates to a launch mission about 29 years ago.” .
The "Long March 5B" rocket was launched by China in 2022, carrying parts of the Chinese "Tiangong" space station (Reuters)
Removing the spacecraft from its orbit to ensure its return to the Earth’s atmosphere within a specific time frame requires a set of procedures, as indicated by Rasha Ghoneim, who, in addition to her presidency, supervises the Space Research Laboratory at the National Institute for Astronomical and Geophysical Research in Egypt. On the space debris monitoring station that will be operated at the institute in a few months, and among these procedures are:
Thrust maneuvers:
If a spacecraft is equipped with propulsion systems, they can be used to gradually lower its orbit over time. By operating its engines in the opposite direction to its orbital motion, the spacecraft reduces its speed, causing its orbit to decay and bring it closer to Earth.
Aerodynamic drag enhancement:
Some spacecraft use drag devices, such as drag sails, inflatable balloons, or extendable structures, to increase atmospheric drag and speed up the orbital decay process. These devices increase the surface area of the spacecraft, which results in increased drag forces that help it reenter the Earth's atmosphere quickly. Larger.
End-of-life burn disposal:
For spacecraft in higher orbits or those with specific re-entry requirements, a controlled burn of the spacecraft's propulsion system can be performed to initiate a more rapid descent, and this burn is timed to ensure that the spacecraft enters the Earth's atmosphere within the required time frame.
Return and disintegration:
Once a spacecraft enters the Earth's atmosphere, atmospheric friction causes the spacecraft to heat up and disintegrate, with most of its components burning up before reaching the Earth's surface, usually located in unpopulated areas or open oceans if the operation is well planned.
“These operations are carefully planned to ensure that the spacecraft reenters the Earth’s atmosphere within a specified time frame and in a controlled manner,” Ghoneim explains. “This helps reduce the risk of debris falling into populated areas and is consistent with regulatory requirements for responsible space operations.”
A rocket and a moon...they are not equal
The European Space Agency did not have a specific time frame for Earth 2's fall, until the Australian commercial imaging company Hue Robotics was able to take pictures of it on February 14, and the agency began tracking its approach to the Earth's atmosphere, and set today, Wednesday, the time 15:19 GMT, with a possible error of plus or minus 19 hours.
The European Space Agency explained in a statement on its website that this uncertainty is due to “the influence of unpredictable solar activity, which affects the density of the Earth’s atmosphere and can therefore change the amount of drag that the satellite pulls on on its way down.” It is still unknown. "It's too early to know where it will fall, but we will have a better idea closer to when the satellite reaches Earth's atmosphere."
Despite the agency's promise that it will be possible to know where it will fall as the date of reaching the Earth's atmosphere approaches, the world does not seem concerned with the place of fall like the Chinese missile, for another reason that Rasha Ghoneim points out, which is the very small degree of danger to the moon compared to the missile.
European Space Agency: The Earth 2 moon weighs 2,294 kg, which is very large for a piece of space debris (European Space Agency)
Ghoneim says: “The majority of the missile’s parts are made of iron, and therefore it will be difficult for all of its parts to burn in the atmosphere. Therefore, falling into populated areas may represent a danger, unlike the Earth 2 satellite, which, despite its huge size, is made of materials that are easy to burn in.” The atmosphere is reduced to small fragments.
The satellite weighs 5,047 pounds (2,294 kg) when empty, as it is now, which is very large for a piece of space debris, but the entry of objects of this size into the Earth’s atmosphere is common these days, and pieces of space junk of a similar mass burn up in the Earth’s atmosphere. Every few weeks, according to an ESA statement.
The agency says: “Earth 2 is expected to break up into smaller fragments once it reaches a height of about 50 miles (80 km) above the Earth, and most of it will burn up in the atmosphere, and some may make its way to the Earth’s surface, but it is expected to fall into the ocean.” None of these parts will contain any toxic or radioactive materials.”
Earth 2 is expected to split into fragments when it reaches an altitude of 80 km, and most of them will burn up in the atmosphere (European Space Agency)
Creating a crisis without justification
In addition to the two previous reasons, Alaa Al-Nahri, Vice President of the Regional Center for Space Sciences at the United Nations, does not deny the role that politics plays, as it seems that there is monitoring of every step that China takes forward in the field of space, and of course there are not these same political motives to do the same thing with Europe. .
Al-Nahri said in a telephone interview with Al-Jazeera Net, “The United States and the West view China as an outsider in the field of space, but despite this, it was able in a short time to achieve achievements, most notably reaching the dark side of the moon, becoming the first country to do so, as it did.” Building its own space station.
The head of the Egyptian Astronomical Society, Engineer Essam Gouda, also points out this political dimension, saying, “Even if the Chinese missile had iron parts, the chances of it falling in a populated area were very weak, but the United States of America created a crisis without justification.”
He added in a telephone interview with Al Jazeera Net that: “It was striking regarding the fabricated crisis in July of 2022 regarding the Long March 5B rocket that was used to send one of the parts of the Chinese space station, that two months before that, China had launched a rocket that was carrying A central part of the Chinese space station module, and the missile then fell after penetrating the Earth’s atmosphere over the Indian Ocean, north of the Maldives, without causing any dangers, but America caused a stir with the second launch, and the missile fell like the first over the Indian Ocean.
The striking irony is that a Canadian study published by the journal Nature Astronomy on July 11, 2022 revealed that the United States does not sometimes do what China has demanded that it do, regarding the necessity of having procedures to ensure that no dangers arise from recovered missiles after launch accidents.
The study said that one of the controls set by the US government, for example, is that the risk of injury be less than a threshold of 1 in 10,000, but the fact revealed by the study is that the US space agency NASA waived this condition seven times between 2008 and 2018. Including the launch of the "Atlas 5" missile in 2015 on a special mission to study the Earth's magnetosphere.
Accordingly, Joudeh believes that “the danger threatening the inhabitants of the Earth, whether from missiles carrying space missions or satellites, appears to be very limited. But if there is a desire for more regulation that makes the possibility of danger non-existent, then in his opinion the matter needs treaties that set binding conditions.” For everyone, not just guidelines.
Source: Al Jazeera + websites