China plans to accomplish a 200-tonne megawatt-level space-based solar power station by 2035, according to the China Academy of Space Technology (CAST).

The space-based solar power station would capture the sun's energy that never makes it to the planet, said Wang Li, a CAST research fellow with the program, when attending the sixth China-Russia Engineering Forum held last week in Xiamen, southeast China's Fujian Province.

The energy is converted to microwaves or lasers and then beamed wirelessly back to the Earth's surface for human consumption, Wang said.

"We hope to strengthen international cooperation and make scientific and technological breakthroughs so that humankind can achieve the dream of limitless clean energy at an early date," Wang said.

Compared with traditional fossil energy, which has been increasingly exhausted and is responsible for severe environmental issues, space-based solar power is more efficient and sustainable, providing a reliable power supply solution for satellites and disaster-hit areas or isolated areas on the Earth, Wang said.

The concept of collecting solar power in space was popularized by science fiction author Isaac Asimov in 1941. In 1968, Peter Glaser, an American aerospace engineer, wrote a formal proposal for a solar-based system in space.

China has proposed various sunlight collecting solutions and made a number of major breakthroughs in wireless energy transmission since the country listed space-based solar power as a key research program in 2008.

However, ambition has long been a challenge for current technology because it involves the launch and installation of numerous solar panel modules and the efficient wireless transmission of mega energy.

With an investment of 200 million yuan (28.4 million U.S. dollars), China is building a testing base in Bishan, southwest China's Chongqing Municipality, for the research of high-power wireless energy transmission and its impact on the environment.

Researches in this field will spur the country's space science and innovation in emerging industries like commercial space transportations, Wang said.

A team of scientists from Taiwan have discovered an approach to manipulate zebrafish's regeneration of missing body parts such as tailfins, which may challenge the existing understanding of how animals "memorize" regeneration.

The research team, led by Dr. Chen-Hui Chen of the Institute of Cellular and Organismic Biology of the Academia Sinica in Taiwan, identified a novel zebrafish mutant and found the mutation can cause tailfins to regenerate with high variability in sizes and shapes, said a press release from the Academia Sinica earlier this week.

They determined DNA "polymerase alpha subunit 2" as the mutated gene and discovered that its activity has a direct impact on blastemal proliferation and size, the statement said.

Some vertebrates like salamanders and zebrafish are known for their remarkable capacity to regenerate complex tissues, such as limbs, tails, and tailfins, and they can regenerate the body part that is exactly the same as the missing one. It remained a mystery of how such positional information is "memorized" to instruct the growth of a perfect replacement.

Through manipulating the activity of this specific gene of zebrafish, Chen and his colleagues developed an approach to effectively rewrite the so-called "positional memory."

The new memory is able to direct the growth of tailfin and scales of zebrafish, even after repetitive injuries, the statement said.

"The importance of these findings is that they provide the first means to alter the fidelity of positional memory. Thus, classic regeneration models that assume the memory is unmalleable may need revisiting and refinement," the press release said.

This study entitled "Genetic reprogramming of positional memory in a regenerating appendage" was published in the international scientific journal "Current Biology" on Nov. 27.

Chinese astronomers have discovered a special population of dwarf galaxies that mainly consist of baryons with radii of up to tens of thousands of light-years, where they are expected to be dominated by dark matter.

The discovery, made by researchers from the National Astronomical Observatories of the Chinese Academy of Science (NAOC), Peking University and Tsinghua University, was published in the latest issue of the science journal Nature Astronomy.

This result provides observational evidence that could challenge the formation theory of dwarf galaxies in the framework of standard cosmology, and may provide new clues to the nature of dark matter, said Guo Qi, a researcher from the NAOC and head of the research team.

In standard cosmology, the universe is dominated by cold dark matter and dark energy, while baryons only occupy 4.6 percent of outer space. Galaxies form and evolve in systems dominated by dark matter.

Statistical studies beyond the Local Group, our neighborhood in the universe, however, were hampered in the past due to the extreme faintness of the dwarf galaxies.

By analyzing the data of the Arecibo Observatory and the Sloan Digital Sky Survey, the research team found 19 dwarf galaxy candidates that are dominated by baryonic masses.

This result is difficult to explain with the standard galaxy formation model, and thus encourages people to revisit the nature of dark matter, Guo said.

Further observations are required to understand the formation of these particularly baryonic-dominated dwarf galaxies, Guo added.

The first cargo-carrying robot marketed directly to consumers is on sale this holiday season. But how many people are ready to ditch their second car to buy a two-wheeled rover that can follow them around like a dog?

Corporate giants like Amazon, FedEx and Ford have already been experimenting with sending delivery robots to doorsteps. Now Piaggio, the Italian company that makes the Vespa scooter, is offering a stylish alternative to those blandly utilitarian machines — albeit one that weighs 50 pounds and costs $3,250.

It's named the Gita (JEE'-tah) after the Italian word for a short, pleasurable excursion — the kind you might take to pick up some lacinato kale and gourmet cheese at the farmers market. Its creators have such trips in mind for the "hands-free carrier" that can hold produce and other objects as it follows its owner down a sidewalk.

"We're trying to get you out into the world and connected to that neighborhood you decided to move to because it was so walkable," said Greg Lynn, CEO of Piaggio's tech-focused subsidiary, Piaggio Fast Forward.

Tech industry analysts are already declaring the Gita as doomed to fail unless it finds a more practical application, such as lugging tools around warehouses, hospitals or factory floors.

"That's a lot of money for what is in effect just a cargo-carrying robot that's going to carry your groceries," said Forrester technology analyst J.P. Gownder.

On a recent November morning, Lynn was hunched over in a Boston waterfront park, pushing a button that triggered a Gita to "see" him with its cameras and sensors. Then came a musical whirring sound as the device — a squarish, bright red bucket with two oversized wheels — rose up and signaled it was ready for a neighborhood stroll.

A young boy in a stroller pointed excitedly. Another pedestrian asked to try it, and playfully shouted "ah!" as it swerved around, keeping in pursuit as she switched directions.

The Gita doesn't require a phone or intrusive people-tracking technology such as facial recognition or GPS. "It basically just locks onto you and tracks you," said Piaggio Fast Forward's other co-founder, Jeffrey Schnapp.

Other startups like Starship Technologies have a more conventional business plan for their own delivery robots. The company charges a delivery fee starting at $1.99 if you order its rovers to bring you a Starbucks coffee or a lunch from Panda Express.

So far, the best habitat to find Starship's six-wheelers are relatively confined spaces such as college campuses; the University of Houston and the University of Wisconsin-Madison rolled them out this fall. The robots, which look like oversized ice chests on wheels, can carry up to 20 pounds.

"I love them. I think they're so cute!" University of Houston freshman Sadie Garcia said as one of the machines rolled up with a bagel sandwich she'd ordered. She said she was so cold she didn't want to leave her dorm.

Starship co-founder Ahti Heinla said his San Francisco startup once looked at selling the machines directly to consumers, but dropped the idea after realizing it would have to price them at more than $3,000.

Amazon is experimenting with a similar-looking machine that delivers retail goods in a handful of U.S. neighborhoods. FedEx is testing its own delivery rover in partnership with Pizza Hut, Walmart, Target and Walgreens. Ford has showed off a gangly two-legged robot to carry items to homes. So far, none are as far along as Starship, which has hundreds of its machines already in service.

While Forrester's Gownder isn't impressed with the Gita, he's bullish about delivery robots of the Starship variety because their autonomy will help save labor costs. Gownder said it's more of a question of whether ground-based rovers or aerial delivery drones will prove more successful.

The wheeled cargo robots that have already made it out into the wild have significant limitations.

Starship's machines still require plenty of manual supervision to load them with food orders. They rely on remote pilots to troubleshoot navigation problems. Customers also have to check a phone app to tell the vehicle where to go and to unlock the bin once it arrives.

The Gita, meanwhile, might still be impractical for many people. It favors paved environments that are dense enough to have stores in walking distance, but not so dense that the machines get lost in the crowd.

And anyone who is simply looking to pull home groceries without heavy lifting can find durable wagons online for less than $100.

NASA's Juno spacecraft has caught a striking view of Jupiter's southern hemisphere as it performed its 23rd close flyby of the giant planet on Nov. 3 this year, said a release of NASA's Jet Propulsion Laboratory (JPL).

The image was taken as the spacecraft sped away from Jupiter. It captures massive cyclones near Jupiter's south pole, as well as the chaotic clouds of the folded filamentary region - the turbulent area between the orange band and the brownish polar region, said the release on Thursday.

When the image was taken, Juno was traveling at about 137,000 kilometers per hour relative to the planet. The spacecraft was about 104,600 kilometers from the planet at a latitude of about -70 degrees, said JPL.

U.S. citizen scientist Ali Abbasi created the image using data from the spacecraft's JunoCam imager.