Lasers and sweeper spacecraft for space junk
GS Paper - 3 (Space Technology)
NASA’s new report weighs the pros and cons of using lasers and “sweeper spacecraft” to help clear space junk. Our planet has a huge space debris problem. From near-miss “worst-case” space disasters to the International Space Station constantly having to move out of the way of space junk, the space debris crisis has prompted concern from both governments and businesses, as well as the scientific community.
Using lasers to clear space junk
- Lasers can exert force on debris in space without making any physical contact.
- In its report, NASA focused on two different laser technologies to help manage space junk from a distance—photon pressure and ablation.
Using photon pressure on space junk
- With the photon pressure technology, lasers nudge debris to ensure collisions don’t happen. A photon is an elementary particle that represents a “quantum of light,” and therefore, they have no mass.
- But while photons are massless, they do carry a small amount of momentum. When a photon (or light, essentially) bounces off an object, it transfers a small amount of that momentum to the object.
- The thrust that comes from this method is too little to de-orbit any kind of debris, but it is just enough to help nudge it away from a collision.
Ablation: Using a powerful laser to cut into space junk
- With the ablation method, a more powerful laser will be used to strike space debris to “ablate,” or erode it.
- When this happens, the piece of debris will eject material from one side, generating thrust in the opposite direction and causing it to move. According to NASA, this ejected material will be a combination of hot gas and plasma and should therefore not contribute any new debris to the environment.
- Compared to the photon pressure method, ablation requires more powerful laser beams and much higher precision.
- Simulations conducted by the space agency indicate that this method can be used to de-orbit debris instead of just redirecting it.
Using a sweeper spacecraft
- If using space lasers to annihilate objects in orbit is a bit too sci-fi for you, NASA is also considering a concept that is slightly more domestic in its inspiration—using a sweeper.
- These sweepers will be large “shields” in orbit that will reduce the amount of space junk by capturing them, slowing them down, or breaking them apart. This method will be especially useful for debris that is too small to be tracked.
- Such a sweeper can be made with a variety of possible materials, including aerogels, foams, clothes or fabrics.
Generative AI behind ChatGPT
GS Paper - 3 (ICT)
Generative artificial intelligence has become a buzzword this year, capturing the public’s fancy and sparking a rush among Microsoft and Alphabet to launch products with the technology they believe will change the nature of work.
What is generative AI?
- Like other forms of artificial intelligence, generative AI learns how to take actions from past data. It creates brand new content – a text, an image, even computer code – based on that training, instead of simply categorizing or identifying data like other AI.
- The most famous generative AI application is ChatGPT, a chatbot that Microsoft-backed OpenAI released late last year.
- The AI powering it is known as a large language model because it takes in a text prompt and from that writes a human-like response.
- GPT-4, a newer model that OpenAI announced this week, is “multimodal” because it can perceive not only text but images as well.
- OpenAI’s president demonstrated on how it could take a photo of a hand-drawn mock-up for a website he wanted to build, and from that generate a real one.
What is it good for?
- Demonstrations aside, businesses are already putting generative AI to work. The technology is helpful for creating a first draft of marketing copy, for instance, though it may require cleanup because it isn’t perfect.
- One example is from CarMax Inc, which has used a version of OpenAI’s technology to summarize thousands of customer reviews and help shoppers decide what used car to buy.
- Generative AI likewise can take notes during a virtual meeting. It can draft and personalize emails, and it can create slide presentations.
- Microsoft Corp and Alphabet Inc’s Google each demonstrated these features in product announcements.
World Happiness Report- 2023
GS Paper -2 (International reports)
Finland has been crowned as the world’s happiest nation, retaining the top spot for the sixth year in a row. The World Happiness Report, published by the UN Sustainable Development Solutions Network(SDSN), ranks countries on happiness.
More about the news:
v It is released on International day of Happiness, observed on March 20; the report ranks global happiness basis survey data from people in over 150 countries.
v It is based on three preceding years’ data of their average life evaluations.
v According to the ranking, many of the same Nordic countries are in the top spots.
v Denmark is at number two, followed by Iceland at number three.
Ranking uses six key factors to measure happiness:
- Social support
- Income
- Health
- Freedom
- Generosity
- Absence of corruption
Why Nordic countries retain top spots:
Ø The Nordic countries merit special attention in light of their generally high levels of both personal and institutional trust.
Ø They also had COVID-19 death rates only one-third as high as elsewhere in Western Europe during 2020 and 2021–27 per 100,000 in the Nordic countries compared to 80 in the rest of Western Europe.
Unlike previous years, where the same countries tend to appear in the top 20, there’s a new entrant this year, Lithuania (at the 20th spot).
India’s position:
Ø According to the report, India ranks at 125th position out of 136 countries, making it one of the least happy countries in the world.
Ø It even lags behind its neighbouring nations like Nepal, China, Bangladesh and Sri Lanka.
More about the report:
v The report also finds particularly interesting and heartening has to do with pro-sociality.
v For a second year, various forms of everyday kindness, such as helping a stranger, donating to charity and volunteering, are above pre-pandemic levels.
v It states that global happiness has not taken a hit in the three years of the COVID-19 pandemic, life evaluations from 2020 to 2022 have been “remarkably resilient”, with global averages in line with the years preceding the pandemic.