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Tiny laser-propelled spaceships could travel to the far reaches of the solar system and beyond – Space.com

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Miniature spaceships the size of cellphones could fly across the solar system using sails propelled by lasers, which would allow the tiny spacecraft to reach much faster speeds — and, potentially, much more distant destinations — than conventionally powered rockets, a new study finds.

Current spacecraft usually take years to make trips within the solar system; for example, NASA’s New Horizons probe took nearly 10 years to reach Pluto

In theory, spacecraft using conventional rockets would need thousands of years to complete an interstellar voyage. For example, Alpha Centauri, the nearest star system to Earth, lies about 4.37 light-years away — more than 25.6 trillion miles (41.2 trillion kilometers), or more than 276,000 times the distance from Earth to the sun. It would take NASA’s Voyager 1 spacecraft, which launched in 1977 and reached interstellar space in 2012, about 75,000 years to reach Alpha Centauri even if the probe were headed in the right direction, which it’s not.

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Related: Is interstellar travel really possible?

The problem with all rocket thrusters is that the propellant they carry with them has mass. Long trips require a lot of propellant, which makes spacecraft heavy, which, in turn, requires more propellant, making them heavier, and so on. 

Previous research has suggested that “light sailing” might be one of the only technically feasible ways to get a spacecraft to another star within a human lifetime. Although light does not exert much pressure, scientists have long suggested that what little pressure it does apply could have a major effect. Indeed, numerous experiments have shown that “solar sails” can rely on sunlight for propulsion if the spacecraft is light enough and has a large enough sail. 

Indeed, the $100 million Breakthrough Starshot initiative, announced in 2016, plans to launch swarms of microchip-size spacecraft to Alpha Centauri, each of them sporting extraordinarily thin, incredibly reflective sails propelled by the most powerful lasers ever built. The plan has them flying at up to 20% the speed of light, reaching Alpha Centauri in about 20 years.

A major challenge Starshot faces is building the lasers needed for propulsion. It calls for a ground-based laser array on the order of 0.4 square miles (1 square kilometer) and as powerful as 100 gigawatts, which would be by far the most powerful laser ever made on Earth.

In the new study, the researchers suggest that a more humble ground-based laser array — one that’s 3.3 to 33 feet (1 to 10 meters) wide and 100 kilowatts to 10 megawatts in power — could still prove useful by sending tiny probes across the solar system, propelling them to much faster speeds than rocket engines could.

“Such lasers can be built already today with a relatively small investment,” study senior author Artur Davoyan, a materials scientist at the University of California, Los Angeles, told Space.com. “We do not need to wait till a 100-gigawatt laser becomes available.”

Going interstellar on a reasonable timescale imposes more constraints than voyaging within the solar system. For instance, Starshot aims to send probes to another star within a human lifetime, so its spacecraft are designed to be extraordinarily lightweight — each just 0.035 ounces (1 gram) or so — to fly as fast as possible given the amount of energy they receive. 

Laser sails for interplanetary voyages, by contrast, do not have to be as lightweight. The scientists envision spacecraft for such trips ranging up to 3.5 ounces (100 g) or so — a mass “comparable with that of a typical cell phone,” Davoyan said.

Whereas Starshot faces mass constraints that make it challenging to fit all the needed spacecraft systems and instruments into a single platform, a 3.5-ounce probe “can easily be equipped with all the needed components, including spectrometers, accelerometers, particle detectors, cameras and so on — all the key ingredients to conduct a proper scientific mission in far reaches of space,” Davoyan said.

Furthermore, because a laser array can launch more than one probe, it could potentially send a fleet of tiny probes, each with different equipment, to a destination. “For example, one may be a magnetometer probe, another equipped with a camera, the third serving as a particle detector,” Davoyan said. “We foresee that many small probes can be sent to really different destinations to do breakthrough science.”

In addition, because interplanetary voyages do not require the kind of powerful lasers needed with Starshot, they also do not require large sails with the kind of extraordinary material properties needed to withstand the many demands of interstellar flight, such as not vaporizing under the light of such a powerful laser. The researchers suggested that silicon nitride or boron nitride sails about 4 inches (10 centimeters) wide should suffice for flights within the solar system.

Related: The solar system: A guide to things orbiting the sun

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“Our work is a first step to fast and low-cost interplanetary and deep space missions,” Davoyan said. “We see that a new model for space exploration can emerge, where individual users, which typically do not have access to space, could now spend just a few thousand dollars and launch a real deep space mission.”

Laser arrays on the order of 100 kilowatts are already under development by the U.S. military; in 2020, for instance, the U.S. Navy’s littoral combat ship USS Little Rock received a 150-kilowatt laser. Furthermore, the cost of high-power lasers is rapidly dropping every year, driven by the need for optical telecommunications, with 1-kilowatt lasers available for less than $10,000, Davoyan noted.

“Rough estimates show that [a] 1-megawatt laser beamer could be constructed with less than $100 million, which is far less than most of NASA’s missions,” Davoyan said. “Importantly, once built, the beamer can be used and reused to launch multiple probes in different directions. Essentially, the laser beamer is an initial capital investment and, once built, serves as a launchpad. The mission cost then consists of producing probes, which, with the use of mass manufacturing, can be on the order of $100, launching probes to orbit for less than $100 per probe and then operating a mission during its useful lifetime. Therefore, overall the laser-driven approach offers very low cost for space exploration.”

The scientists estimated that a 0.035-ounce laser sail with a 4-inch sail driven to speeds of about 112,000 mph (180,000 km/h) could reach Mars in 20 days, compared with the 200 days for NASA’s Perseverance rover; Jupiter in 120 days, compared with five years for NASA’s Juno probe; Pluto in less than three years, compared with 10 years for NASA’s New Horizons craft; and 100 times the distance of Earth from the sun in 10 years, compared with nearly 30 years for NASA’s Voyager 1 spacecraft.

“The fact that we can change the way space is being explored already today with a minimal investment is truly energizing,” Davoyan said. “Such an approach allows almost everyone to develop and launch their own mission — something that was not possible before. It would be really exciting to see an undergraduate student sending their own science probe to, say, Jupiter.”

The scientists now hope to test and prototype their ideas. “We are also partnering with industry and government to move further some of the designs and ideas we have,” Davoyan said. “We believe we can make a real difference in the future of space exploration.”

The scientists detailed their findings online Jan. 31 in the journal Nano Letters.

Originally published on Space.com.

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NASA to launch sounding rockets into moon's shadow during solar eclipse – Phys.org

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This photo shows the three APEP sounding rockets and the support team after successful assembly. The team lead, Aroh Barjatya, is at the top center, standing next to the guardrails on the second floor. Credit: NASA/Berit Bland

NASA will launch three sounding rockets during the total solar eclipse on April 8, 2024, to study how Earth’s upper atmosphere is affected when sunlight momentarily dims over a portion of the planet.

The Atmospheric Perturbations around Eclipse Path (APEP) sounding rockets will launch from NASA’s Wallops Flight Facility in Virginia to study the disturbances in the created when the moon eclipses the sun. The sounding rockets had been previously launched and successfully recovered from White Sands Test Facility in New Mexico, during the October 2023 .

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They have been refurbished with new instrumentation and will be relaunched in April 2024. The mission is led by Aroh Barjatya, a professor of engineering physics at Embry-Riddle Aeronautical University in Florida, where he directs the Space and Atmospheric Instrumentation Lab.

The sounding rockets will launch at three different times: 45 minutes before, during, and 45 minutes after the peak local eclipse. These intervals are important to collect data on how the sun’s sudden disappearance affects the ionosphere, creating disturbances that have the potential to interfere with our communications.

The ionosphere is a region of Earth’s atmosphere that is between 55 to 310 miles (90 to 500 kilometers) above the ground. “It’s an electrified region that reflects and refracts and also impacts as the signals pass through,” said Barjatya. “Understanding the ionosphere and developing models to help us predict disturbances is crucial to making sure our increasingly communication-dependent world operates smoothly.”

A sounding rocket is able to carry science instruments between 30 and 300 miles above Earth’s surface. These altitudes are typically too high for science balloons and too low for satellites to access safely, making sounding rockets the only platforms that can carry out direct measurements in these regions. Credit: NASA’s Goddard Space Flight Center

The ionosphere forms the boundary between Earth’s lower atmosphere—where we live and breathe—and the vacuum of space. It is made up of a sea of particles that become ionized, or electrically charged, from the sun’s energy or .

When night falls, the ionosphere thins out as previously ionized particles relax and recombine back into neutral particles. However, Earth’s terrestrial weather and space weather can impact these particles, making it a dynamic region and difficult to know what the ionosphere will be like at a given time.

It’s often difficult to study short-term changes in the ionosphere during an eclipse with satellites because they may not be at the right place or time to cross the eclipse path. Since the exact date and times of the are known, NASA can launch targeted sounding rockets to study the effects of the eclipse at the right time and at all altitudes of the ionosphere.

As the eclipse shadow races through the atmosphere, it creates a rapid, localized sunset that triggers large-scale atmospheric waves and small-scale disturbances or perturbations. These perturbations affect different radio communication frequencies. Gathering the data on these perturbations will help scientists validate and improve current models that help predict potential disturbances to our communications, especially high-frequency communication.

This conceptual animation is an example of what observers might expect to see during a total solar eclipse, like the one happening over the United States on April 8, 2024. Credit: NASA’s Scientific Visualization Studio

The APEP rockets are expected to reach a maximum altitude of 260 miles (420 kilometers). Each rocket will measure charged and neutral particle density and surrounding electric and magnetic fields. “Each rocket will eject four secondary instruments the size of a two-liter soda bottle that also measure the same data points, so it’s similar to results from fifteen rockets while only launching three,” explained Barjatya. Embry-Riddle built three secondary instruments on each rocket, and the fourth one was built at Dartmouth College in New Hampshire.

In addition to the rockets, several teams across the U.S. will also be taking measurements of the ionosphere by various means. A team of students from Embry-Riddle will deploy a series of high-altitude balloons. Co-investigators from the Massachusetts Institute of Technology’s Haystack Observatory in Massachusetts and the Air Force Research Laboratory in New Mexico will operate a variety of ground-based radars taking measurements.

Using this data, a team of scientists from Embry-Riddle and Johns Hopkins University Applied Physics Laboratory are refining existing models. Together, these various investigations will help provide the puzzle pieces needed to see the bigger picture of ionospheric dynamics.

The animation depicts the waves created by ionized particles during the 2017 total solar eclipse. Credit: MIT Haystack Observatory/Shun-rong Zhang. Zhang, S.-R., Erickson, P. J., Goncharenko, L. P., Coster, A. J., Rideout, W. & Vierinen, J. (2017). Ionospheric Bow Waves and Perturbations Induced by the 21 August 2017 Solar Eclipse. Geophysical Research Letters, 44(24), 12,067-12,073. https://doi.org/10.1002/2017GL076054

When the APEP- launched during the 2023 annular solar eclipse, scientists saw a sharp reduction in the density of charged particles as the annular eclipse shadow passed over the atmosphere.

“We saw the perturbations capable of affecting radio communications in the second and third rockets, but not during the first rocket that was before peak local eclipse,” said Barjatya. “We are super excited to relaunch them during the total eclipse to see if the perturbations start at the same altitude and if their magnitude and scale remain the same.”

The next total solar eclipse over the contiguous U.S. is not until 2044, so these experiments are a rare opportunity for scientists to collect crucial data.

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Royal Sask. Museum research finds insect changes may have set stage for dinosaurs' extinction – CTV News Regina

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Research by the Royal Saskatchewan Museum (RSM) shows that ecological changes were occurring in insects at least a million years before dinosaur extinction.

Papers published in the scientific journal, Current Biology, describe the first insect fossils found in amber from Saskatchewan and the unearthing of three new ant species from an amber deposit in North Carolina, according to a release from the province.

The amber deposit from in the Big Muddy Badlands of Saskatchewan, which was formed about 67 million years ago, preserved insects that lived in a swampy redwood forest about one million years before the extinction of dinosaurs.

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“Fossils in the amber deposit seem to show that common Cretaceous insects may have been replaced on the landscape by their more modern relatives, particularly in groups such as ants, before the extinction event,” Elyssa Loewen, curatorial assistant, said.

The research team was led by Loewen and Dr. Ryan McKellar, the RSM’s curator of paleontology.

“These new fossil records are closer than anyone has gotten to sampling a diverse set of insects near the extinction event, and they help researchers fill in a 17-million-year gap in the fossil record of insects around that time,” Dr. McKellar said.

The three ant species discovered in North Carolina also belonged to extinct groups that didn’t survive past the Cretaceous period.

“When combined with the work in Saskatchewan, the two recent papers show that there was a dramatic change in ant diversity sometime between 77 and 67 million years ago,” Dr. McKellar said in the release.

“Our analyses of body shapes in the fossils suggests that the turnover was not related to major differences in ecology, but it may have been related to something like the size and complexity of ant colonies. More work is needed to confirm this.”

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Meteors, UFOs or something else? Dawson City, Yukon, residents puzzled by recent sightings in night sky – CBC.ca

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Some residents in Dawson City, Yukon, say they’ve been seeing unusual things in the night sky lately — and it’s not the Northern Lights. 

But some might say it’s equally as fascinating.

Over the past few weeks, some residents have taken to social media to report seeing what they described as a fireball or meteor overhead. And last week, two residents said they both saw something similar.

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Naomi Gladish lives in Henderson Corner, a subdivision approximately 20 kilometres from downtown Dawson City. She told CBC News she saw something while walking her dog Friday morning.

“I looked up and saw a bright star,” Gladish said. “Or what I thought was a star.” 

“Within a fraction of a second, I realized it was actually moving quickly. And then as I watched it, a second later it grew a long tail.”

Dawson City resident Naomi Gladish said she saw something similar to the fireball shown in this image from the American Meteor Society. (American Meteor Society)

Gladish said the unknown object started to change into a pale blue colour, like a gas flame. Then, a few seconds later, it appeared to burn out.

“I could see fire, or coal,” Gladish said. “Like red glowing bits, breaking off of it. And then that was it. I tried watching to see if I could see any dark chunks falling from that spot, or carrying on from that spot, but the sky was dark.”

A minute or two after Gladish saw what she thought was a meteor, she heard a boom in the distance.

“My dog and I both turned our head to that exact direction that I had just seen it,” she said.”I figured it was related.”

Two women walking through snowy mountain terrain.
Naomi Gladish hiking with her sister at Tombstone Park. (Submitted by Naomi Gladish)

Dawson resident Jeff Delisle reported seeing something similar at about the same time. He then took to social media to ask if anyone else had seen it. Two people responded saying they had. 

“It flew right above me,” Delisle wrote.

“Pretty cool looking…. What is it?”

Likely not a meteor, says astronomer

Christa Van Laerhoven, president of the Yukon Astronomical Society, came across Delisle’s post and got in touch. She asked about what he’d seen, such as how long it was in the sky and the colour.

Van Laerhoven told CBC News that based on descriptions from both Delisle and Gladish, she doesn’t believe it could have been a meteor.

She says a meteor would have been moving much faster, and the colouring would have appeared differently. 

“Meteors can be any colour but … as a rule, are a consistent colour. What these people were describing had different colours. So the head looked blue and then the tail was more of an orange,” van Laerhoven said.

“That’s just something that doesn’t happen with meteors.”

a meteor
This zoomed-in still from a dashcam video captured in 2020 by Louise Cooke from Mount Lorne, Yukon, shows what one space science expert said appears to be an unusually-bright meteor travelling across the sky. (Submitted by: Louise Cooke)

Van Laehoven believes there may be another explanation for the recent unusual sightings: space junk, falling to earth.

“Space junk, when it comes in … comes through the atmosphere and starts glowing that can be more irregular, because of the variety of materials that go into a spacecraft.”

Van Laerhoven also suggested it could a very fast plane, or someone playing with rockets.

Gladish, however, doesn’t think anyone in Dawson was playing with rockets on Friday morning.

“Unless they’re talking about someone in China, or like a distant land playing with very high, powerful rockets … then sure,” she said.

“This was not something that someone in Dawson was doing … This came from much, much higher and it was much, much different to anything that would be locally caused.”

Van Laerhoven also dismissed another possibility: alien visitors.

“If aliens were coming to Earth, we would know,” she said.

“Simply because it would take them so much effort to get here that it would be very hard to imagine them getting here and not doing something dramatic enough that we would actually know about it.”

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