Daily Current Affairs for UPSC IAS
UPSC Current Affairs: China rocket debris fall in Indian Ocean near Maldives | Page 13 The Hindu
UPSC Syllabus: Prelims: General Science | Mains – GS Paper III – Science & Technology
Context: Debris from the last stage of China’s Long March rocket that had last month carried a key component of its under-construction space station fell into the waters of the Indian Ocean west of the Maldives on Sunday.
Why did the Chinese rocket spark worry?
- When a rocket is launched, its discarded booster stages re-enter the atmosphere soon after liftoff and harmlessly fall into the ocean– a standard practice.
- In this case, however, a 10-floor large vehicle of the rocket weighing 18 metric tonnes went into orbit along with the section of the under-construction space station that it was carrying.
- While in orbit, this vehicle kept rubbing against the air at the top of the atmosphere, and the resulting friction caused it to start losing altitude.
- The piece hurtled through a low-Earth orbit at roughly 25,490 km/hr, traced by the US military, Live Science reported.
- An “uncontrolled re-entry” thus became inevitable, but China did not admit this fact to the world until Sunday, when it said the debris had entered the Earth’s atmosphere over the Mediterranean, flown over the Arabian peninsula and crashed near the Maldives at 72.47° East and 2.65° North.
- Few expected the debris to harm humans, mainly due to most of it burning up in the atmosphere, as well as the fact that large parts of the Earth are covered by oceans and massive land areas lie uninhabited.
- Still, the incident has raised questions about the space technology that China is developing, and the probability of harm being caused to populated areas in the future.
- In May last year, pieces from another Long March rocket of the same 5B variant had crashed on Ivory Coast in what became the largest uncontrolled debris fall since the collapse of the former Soviet space station Salyut 7 in 1991. While no injuries were reported in the crash, many buildings were damaged, according to Reuters.
So, what caused the rocket piece to enter into orbit?
- When rockets carry their payload into space, their booster stages that reach orbit fire the engine again after completing their job so as to drop back to Earth and not remain in orbit. Space agencies plan this process to ensure that such rocket parts end up in uninhabited areas, such as the middle of the ocean.
- According to a New York Times report, China chose not to do this for its Long March rocket, leading to its vehicle crashing back uncontrollably. China’s plan to launch 10 more missions like this until 2022 to complete the Tianhe has thus sparked worry that pieces from its rockets could end up causing injuries.
Have such out-of-control crashes taken place before?
- In March this year, a SpaceX rocket stage made an uncontrolled landing on a farm in Washington state in the US, but this happened due to a malfunction in the engine tasked to bring it down, and not by choice.
- Even before this, in 1979, when the NASA space station Skylab was brought down, some of the debris ended up in Australia, leading to an apology from then-US President Jimmy Carter.
- In 1978, when a nuclear-powered Soviet satellite crashed in Canada, Moscow was forced to bear a part of the expense gone into cleaning the radioactive debris, the NYT report said.