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Tuesday, 3 August 2021

Intuitive Machines to Deliver Jumping Robot to the Moon's South Pole


Arizona State University is partnering with Intuitive Machines on a mini extreme mobility lunar vehicle, called Micro-Nova, that will hop around the moon’s surface and take the first-ever pictures inside craters close to the lunar south pole.

On July 16, 2021, NASA awarded the project a $41.6 million “Tipping Point” contract to develop, fly and operate a deployable lunar “hopper lander” on the moon. For this mission design, Micro-Nova can carry a 1-kilogram payload more than 2.5 kilometers to access lunar craters and enable high-resolution surveying of the lunar surface under the flight path.

“Intuitive Machines' Micro-Nova is our first-ever chance to explore from within a lunar permanently shaded region (PSR),” said the mission science lead Mark Robinson, of ASU’s School of Earth and Space Exploration. “We will be able to take very high resolution color images near the hopper and black and white images of about half the PSR. What will we see, that is the question!”

Micro-Nova will be equipped to provide high resolution stereo images in areas that are in direct sunlight, which will also enable detailed engineering and science planning for future missions.

“This quick trip into a PSR will provide critical engineering information for designing larger-scale exploration over the next decade,” Robinson said. “And we will gain valuable insight to the distribution and migration of volatiles (water) in the lunar environment.”

The hopper will also measure the temperature of the PSR, which will be very cold. Estimates range from about 40 to 80 Kelvin (-388°F to -316°F). Hopper measurements will provide a test of the current temperature models of these areas, which is critical information for other upcoming missions planned to enter PSRs.

With landing gear, Micro-Nova is about 76.2 centimeters in length, width and height, which is roughly the size of five $1 bills. Intuitive Machines engineers will mount Micro-Nova on a nearly 4-meter Nova-C lander, which is about the size of a Volkswagen Beetle. Nova-C will deliver Micro-Nova to the lunar south pole in December 2022.

"There are world-class scientists at ASU’s School of Earth and Space Exploration," said Tim Crain, Intuitive Machines' chief technology officer and co-founder. "Their knowledge of scientific questions and how to get data to answer those questions on the moon coupled with our understanding of engineering systems and how to put instruments in place to collect that data, it's really magical."

About Intuitive Machines     

Intuitive Machines' complete lunar program unlocks the lunar economy to explore the solar system further and gain knowledge for the progress of humanity. As the premier provider of space services and technologies, Intuitive Machines is reestablishing the United States' dominance on the ultimate high ground, the moon. Designed by the greatest minds in spaceflight, IM's lunar program will send the first American spacecraft to the surface of the moon since the Apollo program and send the first spacecraft ever to reach the lunar south pole.

Source: Link

NASA-Boeing Delayed Today's CST-100 Starliner Launch


During pre-launch preparations for the uncrewed test flight of the CST-100 Starliner spacecraft, Boeing engineers monitoring the health and status of the vehicle detected unexpected valve position indications in the propulsion system. The issue was initially detected during check outs following yesterday’s electrical storms in the region of Kennedy Space Center.

Consequently, the launch of the Starliner spacecraft to the International Space Station atop a United Launch Alliance Atlas V rocket will be postponed. The launch was scheduled for 1:20 p.m. ET on Tuesday, Aug. 3. Boeing and NASA teams are assessing the situation. The team will provide updates regarding a launch attempt on Wednesday, Aug. 4.

“We’re disappointed with today’s outcome and the need to reschedule our Starliner launch,” said John Vollmer, vice president and program manager, Boeing’s Commercial Crew Program. “Human spaceflight is a complex, precise and unforgiving endeavor, and Boeing and NASA teams will take the time they need to ensure the safety and integrity of the spacecraft and the achievement of our mission objectives.”

Updates will be provided by NASA and Boeing as information is analyzed and confirmed.

Source: Link

When a Single Tree Makes a Difference


A single tree along a city street or in a backyard can provide measurable cooling benefits, according to a new study from American University. The research shows that “distributed” trees, those that are stand-alone and scattered throughout urban neighborhoods, can help to reduce evening heat. The research suggests that planting individual trees can be a strategy to mitigate urban heat, particularly in areas where land for parks can be scarce.

“There are plenty of good reasons to plant trees, but our study shows we shouldn’t underestimate the role that individual trees can play in mitigating heat in urban areas,” said Michael Alonzo, assistant professor of environmental science and lead author of the new study. “City planners can take advantage of the small spaces that abound in urban areas to plant individual trees.” The study is published in Environmental Research Letters.

While urban parks provide important mid-day cooling for residents and visitors, the key to cooling from individual trees happens in the evening. In the new study, which was conducted in Washington, D.C., cooling benefits from distributed trees were found to occur around 6 or 7 p.m. and after sunset. The study revealed lower temperatures in neighborhoods where at least half the area was covered by canopy from distributed trees. Temperatures were 1.4 degrees Celsius cooler in the evening compared with areas with few trees. Even in the predawn hour, areas with only modest distributed canopy cover (about 20 percent of the area) were cooler than those with no trees, showing that on average, afternoon and evening cooling effects last well into the night, Alonzo added.

To arrive at the findings, Alonzo and his colleagues examined air temperature readings. The data was collected over one hot summer day in 2018, across different areas in Washington, D.C. and at multiple times throughout the day, resulting in more than 70,000 air temperature readings. In their analysis, Alonzo and his colleagues examined tree canopy over paved surfaces, over unpaved surfaces, and both patches such as parks, and distributed trees, such as those one might plant in their back or front yards.

The new study confirms that planting individual trees should be considered as part of a strategy to combat rising temperatures in urban areas. In hot summer months many cities across the United States turn into “heat islands.” Due to the urban heat island effect, urban areas, with fewer green spaces and higher amounts of impervious surface, get hotter compared to their rural surroundings.

In urban areas, people are more likely to live adjacent to distributed trees rather than parks. In D.C., there are many places to plant individual trees where canopy will shade paved or unpaved surfaces: on streets with single family homes, streets with rowhouses, backyard or small park plantings, Alonzo said. This opens up avenues for increasing the racial and socioeconomic equity of tree planting, but more effort is required to first reduce impervious surface cover in the most built-up residential and commercial districts, Alonzo added. The top five trees along D.C.’s streets include several species of maples, oaks and elms, all of which provide plentiful shade.

Climate studies show that urban temperatures are warming at all times of day including evenings. Yet studying the cooling benefits from individual trees, as well as their benefits during evening hours, has not been widely researched, Alonzo said, and this is an area scientists should continue to explore. More research will be needed in other locations in the United States and under different weather conditions. Alonzo also plans to conduct more research and has collected air temperature readings by bicycle around D.C. during the pandemic.

Though the study was conducted in D.C., Alonzo said the findings are likely applicable along the East Coast or in other cities with a similar climate.

“Evenings are not quite the respite from heat that we once had,” Alonzo said. “These distributed trees do help the city cool off in the evening and that’s important for human health.”

Reference: 

Spatial configuration and time of day impacts the magnitude of urban tree canopy cooling by Michael Alonzo, Matthew E Baker, Yuemeng Gao and Vivek Shandas, 9 July 2021, Environmental Research Letters. DOI: 10.1088/1748-9326/ac12f2

Breakthrough: Magnetizing a Material Without Applying an External Magnetic Field


Researchers propose a method of magnetizing a material without applying an external magnetic field.

The study shows that the phenomenon can be produced by means of adiabatic compression, without any exchange of heat with the environment. The process aligns the spins of the material’s particles and magnetizes the system.

Magnetizing a material without applying an external magnetic field is proposed by researchers at São Paulo State University (UNESP), Brazil, in an article published in the journal Scientific Reports, where they detail the experimental approach used to achieve this goal.

The study was part of the PhD research pursued by Lucas Squillante under the supervision of Mariano de Souza, a professor at UNESP’s Department of Physics in Rio Claro. Contributions were also made by Isys Mello, another PhD candidate supervised by Souza, and Antonio Seridonio, a professor at UNESP’s Department of Physics and Chemistry in Ilha Solteira. The group was supported by FAPESP.

“Very briefly put, magnetization occurs when a salt is compressed adiabatically, without exchanging heat with the external environment,” Souza told. “Compression raises the temperature of the salt and at the same time rearranges its particles’ spins. As a result, the total entropy of the system remains constant and the system remains magnetized at the end of the process.”

To help understand the phenomenon, it is worth recalling the basics of spin and entropy.

Spin is a quantum property that makes elementary particles (quarks, electrons, photons, etc.), compound particles (protons, neutrons, mesons, etc.) and even atoms and molecules behave like tiny magnets, pointing north or south – up spin and down spin – when submitted to a magnetic field.

“Paramagnetic materials like aluminum, which is a metal, are magnetized only when an external magnetic field is applied. Ferromagnetic materials, including iron, may display finite magnetization even in the absence of an applied magnetic field because they have magnetic domains,” Souza explained.

Entropy is basically a measure of accessible configurations or states of the system. The greater the number of accessible states, the greater the entropy. Austrian physicist Ludwig Boltzmann (1844-1906), using a statistical approach, associated the entropy of a system, which is a macroscopic magnitude, with the number of possible microscopic configurations that constitute its macrostate. “In the case of a paramagnetic material, entropy embodies a distribution of probabilities that describes the number of up spins or down spins in the particles it contains,” Souza said.

In the recently published study, a paramagnetic salt was compressed in a single direction. “Application of uniaxial stress reduces the volume of the salt. Because the process is conducted without any exchange of heat with the environment, compression produces an adiabatic rise in the temperature of the material. A rise in temperature means a rise in entropy. To keep total entropy in the system constant, there must be a component of local reduction in entropy that offsets the rise in temperature. As a result, the spins tend to align, leading to magnetization of the system,” Souza said.

The total entropy of the system remains constant, and adiabatic compression results in magnetization. “Experimentally, adiabatic compression is achieved when the sample is compressed for less time than is required for thermal relaxation – the typical time taken by the system to exchange heat with the environment,” Souza said.

The researchers also propose that the adiabatic rise in temperature could be used to investigate other interacting systems, such as Bose-Einstein condensates in magnetic insulators, and dipolar spin-ice systems.

Reference: 

Elastocaloric-effect-induced adiabatic magnetization in paramagnetic salts due to the mutual interactions by Lucas Squillante, Isys F. Mello, Antonio C. Seridonio and Mariano de Souza, 3 May 2021, Scientific Reports. DOI: 10.1038/s41598-021-88778-4

Scientists capture most-detailed radio image of Andromeda galaxy to date


Scientists have published a new, detailed radio image of the Andromeda galaxy -- the Milky Way's sister galaxy -- which will allow them to identify and study the regions of Andromeda where new stars are born.

The study -- which is the first to create a radio image of Andromeda at the microwave frequency of 6.6 GHz -- was led by University of British Columbia physicist Sofia Fatigoni, with colleagues at Sapienza University of Rome and the Italian National Institute of Astrophysics. It was published online in Astronomy and Astrophysics.

"This image will allow us to study the structure of Andromeda and its content in more detail than has ever been possible," said Fatigoni, a PhD student in the department of physics and astronomy at UBC. "Understanding the nature of physical processes that take place inside Andromeda allows us to understand what happens in our own galaxy more clearly -- as if we were looking at ourselves from the outside."

Prior to this study, no maps capturing such a large region of the sky around the Andromeda Galaxy had ever been made in the microwave band frequencies between one GHz to 22 GHz. In this range, the galaxy's emission is very faint, making it hard to see its structure. However, it is only in this frequency range that particular features are visible, so having a map at this particular frequency is crucial to understanding which physical processes are happening inside Andromeda.

In order to observe Andromeda at this frequency, the researchers required a single-dish radio telescope with a large effective area. For the study, the scientists turned to the Sardinia Radio Telescope, a 64-metre fully steerable telescope capable of operating at high radio frequencies.

It took 66 hours of observation with the Sardinia Radio Telescope and consistent data analysis for the researchers to map the galaxy with high sensitivity. They were then able to estimate the rate of star formation within Andromeda, and produce a detailed map that highlighted the disk of the galaxy as the region where new stars are born.

"By combining this new image with those previously acquired, we have made significant steps forward in clarifying the nature of Andromeda's microwave emissions and allowing us to distinguish physical processes that occur in different regions of the galaxy," said Dr. Elia Battistelli, a professor in the department of physics at Sapienza and coordinator of the study.

"In particular, we were able to determine the fraction of emissions due to thermal processes related to the early stations of new star formation, and the fraction of radio signals attributable to non-thermal mechanisms due to cosmic rays that spiral in the magnetic field present in the interstellar medium," Fatigoni said.

For the study, the team developed and implemented software that allowed -- among other things -- to test new algorithms to identify never-before-examined lower emission sources in the field of view around Andromeda at a frequency of 6.6 GHz. From the resulting map, researchers were able to identify a catalog of about 100 point sources, including stars, galaxies and other objects in the background of Andromeda.

Reference:

S. Fatigoni, F. Radiconi, E. S. Battistelli, M. Murgia, E. Carretti, P. Castangia, R. Concu, P. de Bernardis, J. Fritz, R. Genova-Santos, F. Govoni, F. Guidi, L. Lamagna, S. Masi, A. Melis, R. Paladini, F. M. Perez-Toledo, F. Piacentini, S. Poppi, R. Rebolo, J. A. Rubino-Martin, G. Surcis, A. Tarchi, V. Vacca. Study of the thermal and nonthermal emission components in M 31: the Sardinia Radio Telescope view at 6.6 GHz. Astronomy & Astrophysics, 2021; 651: A98 DOI: 10.1051/0004-6361/202040011

A Slowdown in Earth’s Rotation Could Have Affected the Oxygen Content of the Atmosphere


Virtually all oxygen on Earth was and is produced by photosynthesis, which was invented by tiny organisms, the cyanobacteria, when our planet was still a rather uninhabitable place. Cyanobacteria evolved more than 2.4 billion years ago, but Earth only slowly transformed to the oxygen-rich planet we know today. “We do not fully understand why it took so long and what factors controlled Earth’s oxygenation,“ said geomicrobiologist Judith Klatt. “But when studying mats of cyanobacteria in the Middle Island Sinkhole in Lake Huron in Michigan, which live under conditions resembling early Earth, I had an idea.”

Cyanobacteria are late risers

Klatt worked together with a team of researchers around Greg Dick from the University of Michigan. The water in the Middle Island Sinkhole, where groundwater seeps out of the lake bottom, is very low in oxygen. “Life on the lake bottom is mainly microbial, and serves as a working analog for the conditions that prevailed on our planet for billions of years”, says Bopi Biddanda, a collaborating microbial ecologist from the Grand Valley State University. The microbes there are mainly purple oxygen-producing cyanobacteria that compete with white sulfur-oxidizing bacteria. The former generate energy with sunlight, the latter with the help of sulfur.

In order to survive, these bacteria perform a tiny dance each day: From dusk till dawn, the sulfur-eating bacteria lie on top of the cyanobacteria, blocking their access to sunlight. When the sun comes out in the morning, the sulfur-eaters move downwards and the cyanobacteria rise to the surface of the mat. “Now they can start to photosynthesize and produce oxygen,” explained Klatt. “However, it takes a few hours before they really get going, there is a long lag in the morning. The cyanobacteria are rather late risers than morning persons, it seems.” As a result, their time for photosynthesis is limited to only a few hours each day. When Brian Arbic, a physical oceanographer at the University of Michigan, heard about this diel microbial dance, he raised an intriguing question: “Could this mean that changing daylength would have impacted photosynthesis over Earth’s history?”

Daylength on Earth has not always been 24 hours. “When the Earth-Moon system formed, days were much shorter, possibly even as short as six hours,” Arbic explained. Then the rotation of our planet slowed due to the tug of the moon’s gravity and tidal friction, and days grew longer. Some researchers also suggest that Earth’s rotational deceleration was interrupted for about one billion years, coinciding with a long period of low global oxygen levels. After that interruption, when Earth’s rotation started to slow down again about 600 million years ago, another major transition in global oxygen concentrations occurred.

After noting the stunning similarity between the pattern of Earth’s oxygenation and rotation rate over geological timescales, Klatt was fascinated by the thought that there might be a link between the two – a link that went beyond the “late riser” photosynthesis lag observed in the Middle Island sinkhole. “I realized that daylength and oxygen release from microbial mats are related by a very basic and fundamental concept: During short days, there is less time for gradients to develop and thus less oxygen can escape the mats,” Klatt hypothesized.

From bacterial mats to global oxygen

Klatt teamed up with Arjun Chennu, who then also worked at the Max Planck Institute for Marine Microbiology and now leads his own group at the Leibniz Centre for Tropical Marine Research (ZMT) in Bremen. Based on an open-source software developed by Chennu for this study, they investigated how sunlight dynamics link to oxygen release from the mats.  “Intuition suggests that two 12-hour days should be similar to one 24-hour day. The sunlight rises and falls twice as fast, and the oxygen production follows in lockstep. But the release of oxygen from bacterial mats does not, because it is limited by the speed of molecular diffusion. This subtle uncoupling of oxygen release from sunlight is at the heart of the mechanism,” said Chennu.

To understand how the processes occurring within a day can impact long-term oxygenation, Klatt and her colleagues incorporated their results into global models of oxygen levels. The analysis suggests that the increased oxygen release due to daylength change could have boosted oxygen levels globally. It is a link between the activity of tiny organisms and global processes. ”We tie together laws of physics operating at vastly different scales, from molecular diffusion to planetary mechanics. We show that there is a fundamental link between daylength and how much oxygen can be released by ground-dwelling microbes,” said Chennu. “It’s pretty exciting. This way we link the dance of the molecules in the microbial mat to the dance of our planet and it’s Moon.”

Overall, the two major oxygenation events (jumps in oxygen concentration) in Earth’s history – the Great Oxidation Event more than two billion years ago and the later Neoproterozoic Oxygenation Event – might be linked to increasing daylength. Hence, increasing daylength could have boosted benthic net productivity sufficiently to impact atmospheric oxygen levels. “Juggling with this wide range of temporal and spatial scales was mind-boggling – and lots of fun,” Klatt concludes.

Reference:

Klatt, J.M., Chennu, A., Arbic, B.K. et al. Possible link between Earth’s rotation rate and oxygenation. Nat. Geosci. (2021). https://doi.org/10.1038/s41561-021-00784-3

Research Shows Common Insecticide Is Harmful to Bees in Any Amount


A new UC Riverside study shows that a type of insecticide made for commercial plant nurseries is harmful to a typical bee even when applied well below the label rate. 

The study was published on July 28, 2021, in the journal Proceedings of the Royal Society B: Biological Sciences. 

Chemically similar to nicotine, neonicotinoids are insecticides that protect against plant-consuming insects like aphids, but seriously harm beneficial insects, like bees. They are widely used by commercial growers.

Much research has focused on their use in food crops like canola, in which they are typically applied at low doses. However, this study is one of the few to examine neonicotinoid application in potted ornamental plants, which can represent more potent, acute sources of exposure to the toxin for bees.

“Neonicotinoids are often used on food crops as a seed treatment,” explained UCR entomologist and lead study author Jacob Cecala. “But they’re usually applied in higher amounts to ornamental plants for aesthetic reasons. The effects are deadly no matter how much the plants are watered.”

Cecala said he was surprised by this result, given that neonicotinoids are water soluble. Going into the study, he assumed that more water would dilute the amount of harm they caused the bees. The researchers were also curious whether increased watering could benefit bees despite insecticide exposure by increasing the quantity or quality of nectar offered by the plants.

To test these assumptions, the researchers raised bees on flowering native plants in pots that either received a lot of watering, or a little. Plants were selected based on their popularity at nurseries, drought tolerance to ensure blooming even without much water, and their attractiveness to bees. In addition, half the plants were treated with the insecticide.

Though increased water decreased the pesticide’s potency in the nectar of the flowers, the negative effects on bees were still observed.

“Unfortunately, we observed a 90% decrease in the bees’ reproduction with both high and low levels of irrigation,” Cecala said. 

This study is also one of the few to examine neonicotinoid effects via ornamental plants on solitary bees, which make up more than 90% of native bee species in North America, and an even higher percentage in California. 

Solitary bees are not bees who have left the hive and are now alone. This is a type of bee that lives alone, does not produce honey, and does not have a queen or live in a hive. Because they do not have a store of honey to protect, they are also not aggressive.

“Solitary bees are more representative of the ecosystem here, and they are potentially more vulnerable to pesticides,” said UCR entomologist and study co-author Erin Rankin. 

If a worker bee that is social — like the honeybee — gets exposed to insecticide and dies, it won’t necessarily affect the longevity of the hive. However, if a solitary bee dies, its lineage is cut short. 

In this study, the researchers used alfalfa leafcutter bees, which make their nests in tunnels and lay eggs one at a time. They are very similar to California’s solitary native bees and are part of a genus that can be found worldwide. 

The first time Cecala and Rankin tried this experiment, they used the concentration of insecticide recommended on the product label. All the bees died in a matter of days. 

The next time they ran the experiment, they used a third of the recommended dose and still found negative effects on reproduction, the ability of the bees to feed themselves, and overall fitness. “It almost completely wiped them out,” Cecala said. 

Though this study used a neonicotinoid product formulated for nurseries, formulations of similar products for home gardeners also tend to be highly concentrated.

Plants in nurseries or residential backyards represent a smaller total area than food plant fields like corn or soy. However, high-potency neonicotinoid products can have a big effect even in small areas. In 2013, neonicotinoids applied to flowering trees in a retail parking lot in Oregon caused a massive bumblebee die off, with more than 25,000 found dead.

The researchers recommend that nurseries quantify the amount of pesticides that are making their way into flowers given their watering and pesticide regimes, and consider alternative management practices that reduce harm to bees and the ecosystems dependent on them. 

“It’s not as simple as ‘don’t use pesticides’ — sometimes they’re necessary,” Cecala said. “However, people can look for a different class of insecticide, try to apply them on plants that aren’t attractive to bees, or find biological methods of pest control.”

Reference: 

Pollinators and plant nurseries: how irrigation and pesticide treatment of native ornamental plants impact solitary bees” by Jacob M. Cecala and Erin E. Wilson Rankin, 28 July 2021, Proceedings of the Royal Society B Biological Sciences. DOI: 10.1098/rspb.2021.1287

ISS Incident Was Worse Than NASA Reported


The New York Times reports that the incident last week when the new Russian Nauka module on the International Space Station unexpectedly fired its thrusters was far worse than NASA reported last week. The rotation of the station went far beyond 45 degrees. NASA Mission Control Flight Director Zebulon Scoville told The Times:

In an interview, Mr. Scoville described how the International Space Station spun one-and-a-half revolutions — about 540 degrees — before coming to a stop upside down. The space station then did a 180-degree forward flip to get back to its original orientation...

The new Russian module is docked on the underside of the space station. When Nauka tried to move, it pulled down the rear of the space station, and the front pitched upward. “It’s exactly like doing a back flip,” Mr. Scoville said.

The rate of rotation reached a maximum of 0.56 degrees a second, Mr. Scoville said. That spinning is not nearly fast enough to generate significant artificial gravity — he said the astronauts reported almost no noticeable change in conditions within the station.…

After about 15 minutes, Nauka’s thrusters petered out. Mr. Scoville said he did not know why, although reports said the module had used up its propellant. The mission controllers could then more easily bring the station to a halt. “After doing that back flip one-and-a-half times around, it stopped and then went back the other way,” Mr. Scoville said.

A key problem was the newly arrived module could only be controlled from the Russian mission control center. The ISS crew couldn’t shut down the thrusters on their own.

Roscosmos has attributed the incident to a software problem.

Source: Link