18-ton section of Chinese rocket crash lands following uncontrolled reentry
If you were awaiting screaming death from the skies, you can relax. For now.
- China's Long March 5 rocket core has landed safely in the Atlantic Ocean following an uncontrolled entry.
- Most of the time, returning hardware that doesn't burn up plunges into the ocean or uninhabited areas.
- There have been two larger returnees in the past, though this one was quite big.
Maybe future generations will look back on these early days of space exploration and chuckle at what we had to suffer through. We live in a time when, every now and then, word goes out that some giant chunk of uncontrolled defunct space junk is about to crash down upon us somewhere, so, um, duck? The hope during such moments is that the deadly debris will land in the ocean that covers most of the Earth's surface or in some unpopulated area, and it usually does. Usually.
Anyhow, if you've been anxiously looking up this week — either at the sky or your ceiling in quarantine — waiting for the core section of China's Long March 5 (CZ-5B) rocket to end you, you can breathe a sigh of relief. It landed safely, for humans anyway, in the ocean off the west coast of Mauritania in northwest Africa on May 11.
Long March into the sea
The CZ-5B-Y1 core stage is in a 155 x 366 km orbit, and is expected to reenter around May 11. At 17.8 tonnes, it is the most massive object to make an uncontrolled reentry since the 39-tonne Salyut-7 in 1991, unless you count OV-102 Columbia in 2003.— Jonathan McDowell (@planet4589) May 7, 2020
Though CZ-5B is one of the largest craft to come down in an uncontrolled reentry, its size is not the only thing that had astronomers like Jonathan McDowell, of the Harvard-Smithsonian Center for Astrophysics, on the edge of their seats. "I've never seen a major reentry pass directly over so many major conurbations!" he tweeted. (A conurbation is an extended urban area.)
While some debris comes down via a controlled landing, that was not the plan for CZ-5B. McDowell tells CNN, "For a large object like this, dense pieces like parts of the rocket engines could survive reentry and crash to Earth." No biggie, he says, since, "Once they reach the lower atmosphere they are traveling relatively slowly, so worst case is they could take out a house."
CZ-5B took off just a week or so ago, on May 5 for just a few days in orbit. Some of its 30-meter-long core stage burned up on reentry, and apparently none of what remained hit anyone, but there are reports of property damage in the Côte d'Ivoire village of N'guinou.
We’ve ducked debris before
A no-doubt radioactive piece of Cosmos 954
Image source: Natural Resources Canada/Wikimedia
At this point, there have been a number of well-publicized spacecraft plummeting down destination-unknown. Probably the scariest was the return of the 4.4-ton Soviet-era spy satellite Cosmos 954. What made its uncontrolled re-entry so frightening is that it was nuclear-powered and threatened to spew radioactive material all over wherever or whomever. The original plan had been to boost it high into a nuclear-safe orbit, but a separation failure doomed the craft to fall back to Earth.
In the end, Cosmos 954 did crash in Northwestern Canada, blowing radioactive debris over a wide area. Canada billed the U.S.S.R $6 million for the cleanup, of which only $3 million was eventually paid.
Probably the first widely publicized uncontrolled return, and one of the two most massive, was of Skylab in 1979. It was another case of a craft coming back earlier than intended, and though NASA couldn't control the 77-ton craft's reentry point, it could control the manner in which it tumbled on down. The nail-biting ended on July 11, 1979, when most of Skylab burned up over the Indian Ocean, though some big pieces survived the descent and landed southeast of Perth, Australia. No one got hurt. The Australian town of Esperance charged NASA $400 for littering. The U.S. also didn't pay up.
Another piece of debris larger than CZ-5B was the Soviet Salyut 7 after nine years in orbit. At the time it came down, it was docked with another spaceship, Cosmos 1686. Salyut 7 weighted in at about 22 tons, as did Cosmos 1686. The connected pair of craft reentered together, burning up and breaking apart over Argentina, with bits raining down on the town of Capitan Bermudez. Amazingly, no one was injured.
One could say we've been pretty lucky so far, though it's hard not to look forward to a time when dying spacecraft can be somehow vaporized out in space where it's safe instead putting those of us down here at absolutely-nothing-you-can-do-about-it risk.
Famous physicists like Richard Feynman think 137 holds the answers to the Universe.
- The fine structure constant has mystified scientists since the 1800s.
- The number 1/137 might hold the clues to the Grand Unified Theory.
- Relativity, electromagnetism and quantum mechanics are unified by the number.
Younger Americans support expanding the Supreme Court and serious political reforms, says new poll.
- Americans under 40 largely favor major political reforms, finds a new survey.
- The poll revealed that most would want to expand the Supreme Court, impose terms limits, and make it easier to vote.
- Millennials are more liberal and reform-centered than Generation Z.
A 2020 study published in the journal of Psychological Science explores the idea that fake news can actually help you remember real facts better.
- In 2019, researchers at Stanford Engineering analyzed the spread of fake news as if it were a strain of Ebola. They adapted a model for understanding diseases that can infect a person more than once to better understand how fake news spreads and gains traction.
- A new study published in 2020 explores the idea that fake news can actually help you remember real facts better.
- "These findings demonstrate one situation in which misinformation reminders can diminish the negative effects of fake-news exposure in the short term," researchers on the project explained.
Previous studies on misinformation have already paved the way to a better understanding<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDU1NzQ4NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxNjE2Mjg1Nn0.hs_xHktN1KXUDVoWpHIVBI2sMJy6aRK6tvBVFkqmYjk/img.jpg?width=1245&coordinates=0%2C800%2C0%2C823&height=700" id="fc135" class="rm-shortcode" data-rm-shortcode-id="246bb1920c0f40ccb15e123914de1ab1" data-rm-shortcode-name="rebelmouse-image" alt="fake news concept of misinformation and fake news in the media" />
How does misinformation spread?
Credit: Visual Generation on Shutterstock<p><strong>What is the "continued-influence" effect?</strong></p><p>A challenge in using corrections effectively is that repeating the misinformation can have negative consequences. Research on this effect (referred to as "continued-influence") has shown that information presented as factual that is later deemed false can still contaminate memory and reasoning. The persistence of the continued-influence effect has led researchers to generally recommend avoiding repeating misinformation. </p><p>"Repetition increases familiarity and believability of misinformation," <a href="https://engineering.stanford.edu/magazine/article/how-fake-news-spreads-real-virus" target="_blank" rel="noopener noreferrer">the study explains</a>.</p><p><strong>What is the "familiarity-backfire" effect?</strong></p><p>Studies of this effect have shown that increasing misinformation familiarity through extra exposure to it leads to misattributions of fluency when the context of said information cannot be recalled. <a href="https://journals.sagepub.com/doi/10.1177/0956797620952797#" target="_blank" rel="noopener noreferrer">A 2017 study</a> examined this effect in myth correction. Subjects rated beliefs in facts and myths of unclear veracity. Then, the facts were affirmed and myths corrected and subjects again made belief ratings. The results suggested a role for familiarity but the myth beliefs remained below pre-manipulation levels. </p>