Farming drones, Ancient bird, Voyager, Wishes
Welcome to Learning English, a daily 30 minute program from the Voice of America. I'm Caty. Weaver. And I'm Mario Ritter Jr.
This program is designed for English learners. So we speak a little slower, and we use words and phrases, especially written for people learning English. On today's program, John Russell reports on unmanned aircraft for agriculture. Jill Robbins has a story about an ancient, bird like animal. Bryan Lynn tells about the Voyager spacecraft on the science report, then wishing on lesson of the day.
But first. American companies are developing unmanned aircraft systems that are larger than drones. The goal is for the aircraft to help agricultural producers and reduce risks to human safety.
When Hector Xue was learning to pilot a helicopter in college, he remembered having a few bad experiences while flying at night. The experiences led him to research unmanned aircraft systems while getting his doctorate at Massachusetts Institute of Technology. Then, Xu formed Rotor Technologies in 2021 to develop unmanned helicopters. Roder has built two autonomous helicopters that the company calls Spray Hawks. Roder aims to have as many as 20 spray hawks ready for market next year.
The company also is developing helicopters that would fly shipments into disaster areas and to oil rigs in oceans. The helicopters could also be used to fight wildfires. For now, Roder is paying attention to agriculture. The industry has accepted automation with drones, but sees unmanned helicopters as a better way to spray larger areas with pesticides and fertilizers. A major appeal of automation in agriculture flights is safety, because special airplanes, called crop dusters, fly at around 240km/h and only about three meters off the ground. There are tens of accidents each year.
The small planes hit power lines, cell towers and other planes. Older planes in disrepair and pilot tiredness play a part in accidents. 2014 report from the National Transportation Safety Board found there were more than 800 agriculture flight accidents between 2001 and 2010, including 81 that were deadly.
A separate report from the National Agriculture Aviation Association found nearly 640 accidents from 2014 until this month, with 109 deaths. It is a very, very dangerous profession, said Dan Martin, a research engineer with the US Department of Agriculture's Agriculture Research Service. Martin said about the pilots, they make all their money in those short few months.
So sometimes it may mean that they fly 10 to 12 hours a day or more. Job risks also include possible contact with farming, chemicals in recent years. Safety and cost concerns have led to a number of drones flying above farmers fields, Martin said. He added that some 10,000 drones will likely be sold this year alone. It's growing exponentially as a market super fast, Martin said.
But the size of the drones means they only can cover a small amount of the area that a plane or helicopter can. The limitation is providing an opening for companies building bigger unmanned aircraft like Rotor and another company, Pica. California based Pica announced in August that it had sold its first autonomous electric aircraft for crop protection, and to a buyer in the United States. Pikas. Pelican spray, a fixed wing aircraft, received official approval last year to fly for crop protection.
The company also sold its Pelican spray to Dole for use in Honduras and to the Brazilian company SLC Agricola. Lucas Coke is chief technology officer at Hainan Brothers Agro Services. The company which but the Pelicans prey in August. Coke has called unmanned aircraft part of a coming revolution that will save farmers money and increase safety. The Kansas based company operates out of airports from Texas to Illinois.
Coke does not see the unmanned aircraft replacing all the company's pilots, but rather taking over the riskiest jobs. The biggest draw is taking the pilot out of the aircraft inside of those most dangerous situations, cook said. But Coke also says that autonomous aviation systems could bring new dangers to an already busy airspace.
Still, the risk is less of a concern in rural areas, with plenty of open space and fewer people. Companies like rotor have developed their systems to work if bad events come up. Rotors helicopter, for example, has a half dozen communications systems and for now, a remote pilot in control.
If the ground team loses contact with the helicopter, rotor has a system to deal with the problem. The system makes sure the engine can be turned off, and the helicopter can perform a controlled landing. The safety measures will go a long way to helping the company receive what it expects will be official government approval to fly its helicopters for business purposes once the company has approval.
The difficulty, as Xu sees it, will be building more devices to meet the demand in the United States and Brazil. I'm John Russell. The brains of today's birds show a level of intelligence and behavioral complexity rivaled only by mammals. But scientists do not fully understand how bird brains have changed over millions of years from the form they had as dinosaurs. That understanding is now growing thanks to a fossil discovery in Brazil. Researchers unearthed the remains, or fossil, of a head, bone or skull of a bird species not known before it has been named.
Another witness, Hestia. The fossil was in such good condition that scientists were able to create a computer image of its brain and inner ear structures, as it lived in a dry area about 80 million years ago, during the Cretaceous period, near the end of the age of dinosaurs. This finding is one of a kind, said University of Cambridge fossil expert Guillermo Avalon, a lead researcher of the study. It appeared this month in the publication Nature. Birds developed from small feathered dinosaurs during the Jurassic period. The novel Ana's Discovery filled in a 70 million year gap in the understanding of the development of the bird dating back to the earliest known bird, Archaeopteryx.
It lived about 150 million years ago in what is now Europe. The researchers said the novel Ana's Skull has a bill and is shaped like modern birds. Its brain shows both modern and ancient elements, and some that are in between. Luis Chiapas is a fossil scientist at the Natural History Museum of Los Angeles County in California, and a co-writer of the study.
He said scientists rarely find such skulls of early birds, and this one is the best preserved ever. Daniel Field is a fossil scientist at the University of Cambridge and the study's lead writer. He said scientists have long struggled to understand how and when the brains and intelligence of birds developed.
The field has been awaiting the discovery of a fossil exactly like this one. He said the novel Ana's brain, measuring about ten millimeters across, is smaller relative to skull size than that of modern birds, but the skull is larger and more complex than that of Archaeopteryx. Its cerebellum, a brain structure that in living birds helps with motor control during flight, was smaller than in today's bird species and more like Archaeopteryx is, but its brain was connected to the spinal cord in a way similar to modern birds as well as humans. It was unlike Archaeopteryx and the dinosaurs from which birds evolved. Nervousness also had something special its inner ear organ for balance is larger than in any other known bird. The fossil included 80% of the birds bone structure or skeleton.
The scientists say they believe the bird could fly well based on their examination of the remains. Field said, if you gave it a quick look, you might think it was like a living bird. But a closer look would show you some important differences, like claws coming out of its wings.
I'm Jill Robins. NASA has once again reconnected with its Voyager spacecraft, marking a continuous portion of the American space agency's longest mission in history. The two spacecraft, Voyager one and Voyager two, launched within weeks of each other in 1977, so they have been operating for more than 47 years.
NASA officials have reported several difficulties with the spacecraft in recent years, mainly communication issues. The most recent problems involved the Voyager one spacecraft, NASA said in a statement in April. It had remained out of touch with the spacecraft for the previous five months. Agency officials said they later learned the problem was linked to a chip inside one of Voyager One's onboard computers. The issue may data being sent by the spacecraft unreadable.
NASA said its engineers were able to fix that problem by making changes to how the spacecraft stores and reads data. Then in October, NASA reported another communication issue that resulted in a brief delay in receiving data from Voyager one. That problem turned out to be linked to the spacecraft's radio transmitter system. The agency said that for some reason, Voyager one's fault protection system was activated when NASA sent a command for the spacecraft to turn on one of its heaters. This activation, meant to save power, led Voyager one to start sending signals to a different radio transmitter system. Then it normally uses.
This meant NASA had to listen for the signals on the S-band instead of the usual X-band. Once they did this, they were able to start receiving data again. NASA has said the S-band is much weaker than the X-band, so engineers were seeking to get the X-band radio communication system back online for long term use.
NASA said the agency had not used the S-band since 1981. Voyager one and Voyager two are NASA's most distant operating spacecraft. The agency has reported Voyager one is exploring space from about 24,000,000,000km from Earth, while Voyager two is operating from about 20.5 billion kilometers away.
Because of this great distance, NASA says its communication with the two Voyagers takes about one day to receive data and another day to send information back from Earth. The two Voyagers were first designed to explore Jupiter and Saturn. Both spacecraft successfully carried out studies of those planets. Later, Voyager two made the first ever close observations of Uranus and Neptune. In 1989.
The two spacecraft then began a new mission to explore distant areas of space. In 2013, NASA announced Voyager one had crossed over the border dividing our solar system from Interstate stellar space. The term interstellar means between stars. Scientists say interstellar space begins where the sun's continuous flow of particles and its magnetic field stop.
Voyager two first entered interstellar space in 2018. NASA said the spacecraft was more than 17.7 billion kilometers from the sun at the time. Both Voyagers are the only spacecraft so far to explore interstellar space. The space agency says the Voyagers are studying how the interstellar medium interacts with the solar wind. Solar wind is the continuous flow of charged particles released by the sun.
The spacecraft have also provided data on the heliosphere, a kind of protective bubble around our solar system. Suzanne Dodd is the current project manager for the Voyager mission at NASA's Jet Propulsion Laboratory in California. She recently said in a statement the agency has no plans to retire the two Voyagers as long as they are communicating with mission members back on Earth. Dodd said the spacecraft are currently centered on observing how interstellar space and the heliosphere interact with each other. We wouldn't be doing Voyager if it wasn't taking science data, she added. Dodd noted one reason the Voyagers have been operating for so long is that the engineers who built them provided multiple backup systems to avoid future problems.
She said some who worked on Voyager in its earliest days have even come back from retirement to pass on knowledge to the next generation of scientists and engineers. From where I sit as a project manager, it's really very exciting to see young engineers be excited to work on Voyager, Dodd said. To take on the challenges of an old mission and to work side by side with some of the masters, the people that built the spacecraft. They want to learn from each other.
I'm Bryan Lynn. Welcome to the lesson of the day on the Learning English Podcast. My name is Andrew Smith. And my name is Jill Robins.
Thanks for joining us. Today's lesson will help you learn more about the English you hear. In our video series, let's Learn English. The series shows animate Teo and her work and life in Washington, D.C..
Here's Ana introducing herself. Hello. My name is Ana Mateo. In our previous lesson of the day, we heard Ana and her friend Bruna talk about hopes and wishes. In today's podcast lesson, we're going to give you more ways to practice using the verb wish. But first, let's listen to Ana and Bruna again.
This is from lesson ten of level two of the Let's Learn English series. Hi, Ana. Hi, Bruna. What's up? I thought we could meet for lunch today. I wish I could, but I can't. I have to research Peru for a story.
How's it going? Not so good. I've been reading about Peru and listening to Peruvian music. I really want to understand Peru. I hope it's enough. We wish for things we can't do, have or be. That means we wish for things that are different from how things are now.
To show this difference, English changes the form of the verb or modal that follows the word wish, for example, can change this to could have changes to had is changes to were was, changes to had been, and so on. So it sounds like this. I wish I could.
I wish I had. I wish I were. I wish I had been. Of course, those are not complete sentences. So now we'll explain how you can practice making sentences with the word wish first. Right? Or think of a sentence that describes a real situation in the present or in the past. Then use a sentence with which to express the idea that we want a different situation.
Jill and I are going to give you some examples. First we say one thing and then we wish that thing were different. Are you ready, Jill? Ready? I can't swim. I wish I could swim. I don't understand the question.
I wish I understood the question. My head hurts. I wish my head didn't hurt. Okay. Notice that after the word wish, we use a word that sounds like we are talking about the past. But we are not talking about the past.
Listen again to this example. I don't understand the question. I wish I understood the question.
The verb understand changes to understood. But we're not talking about the past. In fact, we want to understand the question now. But because. Which means that it is not possible at the present time for us to understand. We change the verb to understood.
We could also say, I wish I could understand the question. This change of the verb form also happens in conditional statements, like sentences that start with the word. If right. For example, we say, if I had more time, I would study more.
The verb had does not mean the past. Instead, it shows a situation that is not real because it comes after the word. If. Okay.
Now let's give more examples with wish. Are you ready again, Jill? Ready? I didn't see the game. I wish I had seen the game.
He is not here. I wish he were here. I smoke cigarets.
I wish you didn't smoke cigarets. They talk really fast. I wish they didn't talk so fast. Then you are not at the party. I wish you had been at the party.
Notice that for real statements about what people do, we change it to negative. When we use wish. They talk really fast.
I wish they didn't talk so fast. In the same way, the negation shown by the word not disappears when we use wish. I didn't see the game. I wish I had seen the game. Now it's your turn, listeners. We will say a sentence about a real situation, and then give you time to say a sentence using the word wish.
After you will hear us say a sentence using the word wish so you can compare your answer. Are you ready? Okay, here we go. Sentence number one I can't visit my family.
I wish I could visit my family. Sentence number two. I don't have a car.
I wish I had a car. Sentence number three. He is always late. I wish he weren't always late. Sentence number four. They are not here.
I wish they were here. Sentence number five. I didn't go to the beach. I wish I had gone to the beach. Sentence number six. She didn't help me.
I wish she had helped me. Sentence number seven. She never talks to me. I wish she would talk to me. Sentence number eight.
I don't know how to swim. I wish I knew how to swim. Listeners, how well did you do? Was it easy or difficult to change your sentences and use the word wish? There are a lot of forms to learn, so don't worry if you could not change all the sentences, but you can always go back and play the examples again and try to save the sentences with the word wish. We hope these exercises will be helpful. Now, before we finish, here's a little chart with more examples using the word wish. Ready? Listen.
I can't sing, but I wish I could. And you don't dance. But I wish you would. You don't cook and you don't try. I wish you would cook. And I wish you would try. I would if I could, but I don't have the time.
I wish we had a much longer day. I do too, but what else can we say? How about this? We wish we had more time with you. We wish we did. You know it's true. But it looks like time is running out.
So one more thing before we go. We hope you'll write us and let us know something that you wish that we would do to help you learn and have fun, too. Well, we really do have to go now. Write to us and tell us your wishes at Learning English at VOA News.com.
And remember, you can also find us on YouTube and Instagram and Facebook. I'm Jill Robbins. Thanks for listening. I'm Andrew Smith.
And that's our show for today. But join us again tomorrow to keep learning English on the Voice of America. I'm Caty Weaver. And I'm Mario Ritter Jr.
2024-11-27 20:19
