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The protein dress of a neuron – Science Daily



Where in a nerve cell is a certain receptor protein located? Without an answer to this question, it is difficult to draw firm conclusions about the function of this protein. Two scientists at the Max Planck Institute of Neurobiology developed a method in the fruit fly that marks receptor proteins in selected cells. In this way, they gained new insights into the neuronal mechanisms of motion vision. In addition, the research community receives an innovative tool to label proteins of all kinds.

One of the most fundamental questions in neurobiology is how sensory inputs are processed within the neuronal circuits of the brain. Thereby, it is not only important to understand which neurons are connected via synapses, but also how they communicate with each other. Receptors play a decisive role in this process.

These special proteins sit in the membrane envelope of neurons and specifically at synapses, where they receive incoming signals from other cells. Depending on receptor type and position, they determine how the cells react to incoming information: are they activated or inhibited, and how quickly does this happen? To understand a neural network in its entirety, it is therefore essential to study receptors and their distribution in neurons. However, this is not an easy task.

Some established methods provide little or no information about the distribution of proteins. Other techniques allow the labelling of receptors artificially introduced into cells, but not of naturally occurring ones. Therefore, the PhD students Sandra Fendl and Renee Vieira from Alexander Borst’s department used the genetic resources available in the fruit fly Drosophila and developed a method to label proteins.

With the new technique, endogenous receptors are labeled with the green fluorescent protein — and only in selected cells. The latter is essential for assigning the labeled receptors within the dense neuronal network to those cells that are of particular interest.

Using this method, the scientists analyzed receptors in neurons that process movements in the visual system of the fruit fly. They found that different receptors are not randomly arranged along neurons. Even within a dendrite, the part of a neuron that receives incoming signals, receptor proteins are distributed in a very characteristic way.

With a precision of a few micrometers, the study shows, which synapse meets which receptor along the dendrite. Now predictions can be made about the properties of individual nerve cell connections. This adds another important puzzle piece towards a comprehensive picture of the neuronal circuits in the visual system of the fruit fly.

But that’s not all: the new tool can be easily extended to thousand other proteins as well. In the future, countless proteins can be labeled and examined in selected cells — and this goes clearly beyond the specific neurobiological question of fly motion vision.

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Materials provided by Max-Planck-Gesellschaft. Note: Content may be edited for style and length.

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Connecting Earth With the Moon: Lunar Satellites – SciTechDaily



Since time immemorial, people have gazed in wonder at the Moon. Its gentle light suggests romance, its strong embrace powers the tides and it is even sometimes blamed for madness.

The Moon was once the domain of the gods; many mythologies feature lunar deities. But humans are explorers, setting sail to discover new worlds and, five decades ago, Earth’s natural satellite received its first visitors.

Now as international teams across the world forge plans to revisit the Moon, ESA is elaborating how best to facilitate this exploration.

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Lunar exploration relies on the extensive expertise that is on hand across ESA. As a new lunar economy emerges, it will create new opportunities involving robots, habitats and transportation. Missions to the Moon share similar communication and navigation needs that could be satisfied using a constellation of lunar satellites. Under the agency’s “Moonlight” initiative, ESA is exploring with industry the necessary technical solutions along with delivery models for the provision of lunar telecommunication and navigation services. Credit: ESA

Bold ambitions

The Moon is our nearest neighbour in space. Its enticing proximity makes it the natural place to test how people can take the next steps to Mars and beyond.

Bold ambitions foresee exploring the lunar polar regions through international cooperation, with dozens of very different commercial and institutional missions to the Moon already planned for this decade.

NASA’s Artemis programme plans to return humans to the Moon by 2024 and, in cooperation with ESA and other partners, intends to put a Gateway with living quarters for astronauts in lunar orbit. The Gateway will be home to European astronauts as well as those from around the world, and it will have a communications module developed by ESA.

Lunar Missions Overview

An overview of missions to the Moon. This infographic shows the interest in commercial and institutional organisations in launching spacecraft to the Moon. Credit: ESA

ESA is working on plans for a European Large Logistic Lander to provide different types of uncrewed missions, from supply runs for Artemis astronauts, to stand-alone robotic science and technology demonstration missions and even a lunar return mission to bring samples to laboratories on Earth. It envisages regular launches starting in the later part of this decade and continuing into the 2030s.

Before then, a Lunar Pathfinder spacecraft designed to provide affordable communications services to lunar missions is due to be launched, perhaps by the end of 2022. Developed in collaboration with ESA, the spacecraft will be a mission enabler for polar and far-side missions which, without direct line-of-sight of the Earth, would otherwise have to procure their own communications relay spacecraft.

Many other initiatives come from the main space institutions in China, India, Japan and Russia, as well as private entities across the globe.

Heracles Approaching Landing Site

Artist’s impression of Heracles approaching its landing site on the Moon. A European lander is planned within the next 10 years. Credit: ESA/ATG Medialab

Project Moonlight

To succeed, each of these ambitious plans requires reliable navigation and telecommunication capabilities. Building these independently would be costly, complex and inefficient.

If this work were outsourced to a consortium of space companies that could put a constellation of satellites around the Moon, each individual mission would become more cost-efficient.

ESA Moonlight Logo

Having one system dedicated to lunar telecommunications and navigation could reduce design complexity, liberating missions to concentrate on their core activities.

Because missions could rely on this dedicated telecommunications and navigation services, they would be lighter. This would make space for more scientific instruments or other cargo.

An accurate and reliable telecommunications and navigation service would enable missions to land wherever they wanted. Radio astronomers could set up observatories on the far side of the Moon. Rovers could trundle over the lunar surface more speedily. It could even enable the teleoperation of rovers and other equipment from Earth.

For the past three years, ESA has been working along with industrial partners to explore the lunar market. As part of an initiative called Moonlight, ESA is now conducting deep analyses of the planned lunar missions and further developing possible solutions, both technical and business-related, to provide telecommunications and navigation services for the Moon.

Illuminating the possibilities

The Moon’s orbit is tidally locked to the Earth, which means that it rotates once as it circles the planet. As a result, it always shows the same face to Earth.

A constellation of lunar satellites would enable missions to keep in constant contact with Earth, even when on the far side of the Moon. This constellation could also allow lunar navigation in areas without direct to Earth visibility, supporting for example the landing of scientific equipment exactly where they intended, no matter how remote the location.

Prospection Moon Base

An artist’s impression of what a lunar base could look like. Credit: ESA – P. Carril

It would allow missions to the polar regions of the Moon to keep in touch with Earth and with any lunar base.

Finally, lowering the ticket price to lunar exploration could empower a wider group of ESA member states to launch their own national lunar missions. Even on a relatively low budget, an emerging space nation would be able to send a scientific cubesat mission to the Moon, inspiring the next generation of scientists and engineers.

The lunar satellites would provide communication and navigation signals for all these missions, ensuring adequate positioning services and constant connectivity for ground control and for scientists on Earth.

Exploring solutions

Over the past few years, ESA has conducted several feasibility studies, internally and in collaboration with industry, to understand the lunar market, its user and business parameters, and to explore the possible technical implementations of such an infrastructure.

Preliminary concepts include several satellites in different orbits around the Moon providing lunar missions with reliable, real-time communications and navigation services.

The navigation services could support mission-critical operations such as lunar orbit, lunar landing, real-time rover driving and lunar ascent.

The data capacity between Earth and the Moon would gradually exceed several hundreds of megabits per second for aggregated relay services, allowing lunar missions data capacities that compare well to home television and film streaming.

Demand for data is predicted to increase steeply after 2028.

Next steps

ESA invited companies that are prepared to study and design a lunar constellation to express their interest in the Moonlight initiative. The agency has entered into talks with interested parties, which have now prepared outline proposals that highlight their background and experience, and explain their proposed business and service model, partnership proposition and draft system concept. This is the first part of a two-stage tendering process. In the second stage, the agency will invite selected companies to submit a final tender for a detailed definition of the end-to-end service.

Up to two parallel fully funded contracts are envisaged with ESA. These contracts are expected to be awarded in early 2021.

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Watch Out for the Penumbral Eclipse This Monday: Here's How – Science Times



According to NASA, on early Monday morning, November 30, skywatchers will get to see another November full moon treat as the penumbral eclipse happens. It is an event when the Moon passes through the outer shadow of the Earth.

It will take four hours and 21 minutes for the Moon to glide across the pale outer fringe (penumbra) of the Earth’s shadow but never meeting the dark umbra of the shadow. A penumbral eclipse is rather a minor astronomical event that is usually difficult for many people to detect unless at least 70% of the Moon’s diameter is immersed in it, reported.

For a moment, the Moon will be at its fullest on November 30, at 4:30 am EST. But it will appear full starting on Saturday, November 29, until Tuesday, December 1.

(Photo: Pixabay)
Watch Out For the Penumbral Eclipse This Monday: Here’s How

Read Also: Penumbral Eclipse, Leonid Meteor Shower, and More: November Sky Events To Watch Out For

A Penumbral Eclipse

Penumbral eclipses differ in many aspects from total or partial lunar eclipses, according to ScienceAlert. Earth passes directly between the sun and the Moon during a total lunar, which blocks the sun’s light from entering the Earth’s natural satellite.

Moreover, the Moon passes through a part of the Earth’s dark shadow, known as the umbra, during partial eclipses, unlike the penumbral eclipse that glides through the pale outer part of the planet’s shadow.

According to NASA, “the dimming of the moon during this eclipse will probably not be noticeable without instrumentation, but for spacecraft at the moon such as the Lunar Reconnaissance Orbiter (LRO), the reduction in solar power will be noticeable.”

November’s full moon is also called the beaver moon that comes late this year because October this year had two full moons: the harvest moon and the blue moon; the first time in over 76 years, a full moon was visible across the US during Halloween.

This month’s full moon comes in many names, like the cold moon, frost moon, oak moon, child moon, the winter moon, and the moon before Yuletide.

According to NASA, the full moon is also celebrated by different cultures worldwide, such as during the Kartik Purnima celebrated by the Hindu, Sikh, and Jain. Likewise, the Hindus celebrate Karthika Deepam, Buddhists in Myanmar and Burma celebrate the Tazaungdaing Festival Moon, and Ill Poya is celebrated in Sri Lanka.

Seeing the penumbral eclipse from the moon reports that an astronaut on the Moon during the penumbral eclipse will be able to witness an eclipse of the sun, depending on what specific part of the Moon is the astronaut standing. But as seen from the Tycho crater, the Earth’s silhouette will hardly cause any noticeable diminishing of the light on the Moon’s surface.

But when looking from the upper limb of the moon in the Mare Frigoris, a region also known as the “Sea of Cold,” the Earth will appear to cover more than eight-tenths of the sun’s diameter. As a consequence, solar illumination on the Moon will be considerably somber.

This diminished sunlight on the Moon is what people on the Earth’s Northern Hemisphere will try to detect during the penumbral eclipse on Monday.

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Read More: What Makes The Upcoming Hunter’s Blue Moon Rare

Check out more news and information on Eclipse and Full Moon on Science Times.

©2017 All rights reserved. Do not reproduce without permission. The window to the world of science times.

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China's Chang'e-5 probe enters lunar orbit – ecns



China’s Chang’e-5 probe decelerated and entered the lunar orbit on Saturday, completing a vital step on its way to collect and return moon samples, the China National Space Administration (CNSA) announced.

After flying about 112 hours from Earth, an engine on the probe ignited when it was 400 km away from the surface of the moon at 8:58 p.m. and shut down after about 17 minutes, the CNSA said.

The probe performed the braking without incident and entered the lunar orbit successfully, according to the real-time monitoring data.

Chang’e-5, comprising an orbiter, a lander, an ascender, and a returner, has carried out two orbital corrections during the Earth-Moon transfer, achieving its expected goals.

Afterward, it will adjust the altitude and inclination of its orbit around the moon. When the time is appropriate, the lander-ascender combination will separate from the orbiter-returner combination, implement a soft landing on the near side of the moon, and carry out automatic sampling as planned.

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