Month: July 2021

In May 2018, NASA’s interior exploration with seismic investigations, geodesy and heat transport (InSight) landed on the surface of Mars. This mission is the first of its kind, as all previous orbiters, landers and rovers have focused on studying the surface and atmosphere of Mars. In contrast, InSight was tasked with characterizing the internal structure of Mars and measuring the core, mantle and crust by reading its seismic activity (also known as “Marsquakes”).

The aim is to learn more about the geological development of Mars since its formation 4.5 billion years ago, which should also provide insights into the formation of the earth. According to three recently published articles, the data obtained by InSight has led to new analyzes of the depth and composition of the Martian crust and mantle and confirmed the theory that the planet’s inner core has melted.

The three studies that appeared in the July 23rd issue of Science were directed by Brigitte Knapmeyer-Endrun from the Bensberg observatory at the University of Cologne; Amir Khan, researcher at the Physics Institute of the University of Zurich; and Simon Stähler, researcher at the Institute for Geophysics at ETH Zurich. These publications addressed the new knowledge about the thickness and structure of the Martian crust, the upper mantle structure, and the molten core (each).

Clouds move over the dome-covered seismometer known as SEIS, which is part of NASA’s InSight lander on Mars. Photo credit: NASA / JPL-Caltech

Bruce Banerdt, InSight’s lead researcher at NASA’s Jet Propulsion Laboratory (JPL), said in a recent press release from NASA JPL: We were hoping to be finished. This is the culmination of all the work and worries of the past ten years. “

The data that led to all three publications came from InSight’s seismometer known as the Seismic Experiment for Interior Structure (SEIS). On Mars, seismic activity is largely the result of surface impacts that cause sound waves to travel through the mantle and core to the other side of the planet. The ultra-sensitive SIES was developed so that scientists can hear these sound waves, the speed and shape of which vary depending on the material.

These variations have given seismologists an opportunity to study the internal structure of Mars and learn more about how all rocky planets – including Earth, Venus, and Mercury – work. In all cases, the rocky planets formed from the protoplanetary disk, which consisted of dust and meteoric material left over when the sun was formed. When this material came together, it became a giant ball of molten silicate minerals, metals, and other elements.

Over the course of tens of millions of years, the planet cooled and differentiated into three different layers – the crust, mantle, and core – with the lighter silicate elements settling near the tip and heavier elements (such as iron and nickel) in the core. Measuring the depth, size and structure of these three layers has always been a central part of InSight’s mission and the purpose for which SEIS was developed.

NASA’s InSight lander discovered on July 25, 2019, the 235th seismologists examine the wobble in seismograms to confirm whether they are really seeing a quake or a sound made by the wind. Photo credit: NASA / JPL-Caltech

Since the SEIS was first placed on the Martian surface, it has recorded 733 different Martian quakes, 35 of which (all between magnitudes 3.0 and 4.0) provided the data for all three papers. From this data, Knapmeyer-Endrun and her colleagues determined that the Martian crust is thinner than expected and may have two or three sub-layers. If there are two sub-layers, the crust extends 20 km (12 miles) below the surface or 37 km (23 miles) if there are three.

Meanwhile, Khan and colleagues found that the mantle extends 1560 km (969 miles) below the surface, while Stähler and colleagues found that the core is liquid and has a radius of about 1830 km (1,137 miles). This study is a unique opportunity, ”says Stähler. “It took scientists hundreds of years to measure the Earth’s core; after the Apollo missions it took them 40 years to measure the core of the moon. It took InSight only two years to measure the core of Mars. “

One surprising find was that all of the most significant marsquakes discovered by InSight came from one area: Cerberus Fossae, a region that is volcanically active enough that geophysicists believe that lava may have flowed there in the past eons. This is based, in part, on images captured by orbiting spacecraft that discovered rocky tracks and other landslide features that appear to have been caused by marsquakes.

Another surprise was that none of these quakes came from the more prominent volcanic regions like Tharsis, where the three of the largest volcanoes on Mars are (collectively known as Tharsis Montes). However, there can be many quakes (large and small) that InSight cannot detect due to shadow zones caused by the core breaking seismic waves away from certain areas.

The two largest quakes detected by NASA’s InSight appear to have originated in a region of Mars called Cerberus Fossae. Credits: NASA / JPL-Caltech / Univ. from Arizona.

Meanwhile, InSight’s seismometer detects new marsquakes every day, and the mission team is hoping to detect a marsquake greater than 4.0. “We’d still love to see the big one,” said JPL’s Mark Panning, co-lead author of the paper on the crust. “We have to do a lot of careful processing to get what we want from this data. A bigger event would make everything easier. “

These results are the first of many to come from InSight’s seismic data, which is helping scientists refine their models of Mars and how it was formed. They will also provide valuable information on how Mars lost its magnetosphere about 4.2 billion years ago, followed by the slow depletion of its atmosphere by solar wind over the course of several hundred million years.

This process resulted in Mars moving from a warmer, wetter planet that could have hosted microbial life on its surface, to the icy and arid planet it is today. Knowing how and why this transition occurred will also shed light on how terrestrial planets remain (or do not) inhabitable as they evolve. This knowledge will also help astrobiologists who want to characterize extrasolar planets and limit their potential habitability.

The research was also the subject of a live streaming discussion held on Friday, July 23rd, on NASA TV (which you can watch below), as well as on the NASA app, the agency’s website, and YouTube and Facebook Channels of the JPL appeared. The panel included Mike Panning from NASA Jet Propulsion Laboratory, Amir Khan and Sabine Stanely from John Hopkins University.

Further reading: NASA

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Reposted by MANHATTAN CONTRARIAN

July 28, 2021 / Francis Menton

If you as a state or country want to have a status in the ranks of the climate virtues, the key metric is your commitment to get most or all of your energy from “renewable energies” (primarily wind and sun) as early as possible. Everyone does it, and you are nobody if you don’t bid. Just a few weeks ago (July 14th) the European Commission placed a bid of 40% of the final energy consumption from “renewable” sources by 2030, according to Reuters. Back here in the US, the Biden government’s most recent bid (dated 28th. Congress has yet to consider the Biden government’s offer.

In both the EU and the US there are national and state champions that far surpass all others. In the EU it is Germany. Germany already decided on its energy turnaround in 2010 in order to convert its energy sector to wind and sun. Since then, Germany has repeatedly raised its targets for renewable energies. Most recently, in December 2020, Germany passed a binding target of 65% electricity from renewable energies by 2030. Our champion here in the US is California. In California, the governing law is the famous SB 100, which was passed in 2018 and sets mandatory targets for the electricity sector of 60% “renewables” by 2030 and 100% by 2045.

As the readers here know, the Manhattan Contrarian has from time to time expressed high levels of skepticism as to whether these mandatory goals are achievable in the real world. In fact, I have often found that with around 40-50% of “renewable” electricity, it becomes virtually impossible to increase the proportion of electricity from renewables simply by adding more renewable capacity. As far as I know, no major jurisdiction has so far increased the proportion of electricity generated from “renewables” to over 50% over a longer period of time. (If a reader can give me an example, I would be very interested.)

But maybe I’m just a weirdo. These geniuses in Germany and California must surely know what they’re doing. So let’s check out the latest news.

Germany

On July 27, the No Tricks Zone website published a report on electricity production in Germany for the first half of 2021. No Tricks Zone’s post is based on data compiled on a German website called Die kalte Sonne.

And the answer is: In the first half of 2020, Germany reached the level of 50% of its electricity from “renewables”. But in 2021 that number dropped to 43%:

“The share of renewable energies in gross electricity consumption fell from 50% to 43% in the first half of 2021 compared to the previous year,” reports Die kalte Sonne.

What happened? The wind just wasn’t that strong:

“The production of onshore and offshore wind energy decreased by 20%.” . . According to the findings, the reason for the steep drop was unfavorable weather conditions. “This year, especially in the first quarter, the wind was particularly calm. . . . “

Has solar energy then closed the gap? Unfortunately, not:

“[T]The solar output was low. . . . Solar energy performance. . . increased by a modest 2%. “

How did Germany make up for the difference? The answer won’t surprise you:

“Coal energy was experiencing a renaissance. Brown coal [lignite] Power plants produced 45.8 terawatt hours of net electricity – that is the electricity mix that comes out of the socket. That is a sharp increase of 37.6% compared to 2020, when only 33.6 terawatt hours were produced. The net production of the hard coal power plants also rose by 38.9% to 20.4 terawatt hours after 14.4 terawatt hours in 2020. “

In principle, Germany is reaching the limit of what can be achieved by expanding wind and solar power sources. To achieve the higher “renewable” market share they are committed to, they need to add large and rapidly growing amounts of grid storage. So far, they have barely started this process.

California

You may recall the excited LA Times April 29 headline, “California Just Got 95% Renewable Energy.” April 29 was the very day after President Biden announced his goal of 80% of the US by 2030 -To obtain electricity from “renewable energies”. Now California has already shown the world that they are way ahead and basically reach the home plate:

Something remarkable happened over the weekend: California has achieved nearly 95% renewable energy. I’ll say it again: 95% renewable. With all the time we spend talking about how to achieve 100% clean electricity, it sometimes seems like a distant suggestion whether the timeframe is California’s 2045 goal or President Biden’s more aggressive 2035 goal is. But on Saturday just before 2:30 p.m., one of the world’s largest economies was just a stone’s throw away.

(Italics in the original.). But maybe we shouldn’t get too upset just yet. Although the author (Sammy Roth) says this is “95% renewable energy”, on further reading it turns out that he is only talking about electricity, which is only about 30% of energy consumption. And how long did renewables cover 95% of electricity consumption?

Saturday’s 94.5% figure – a record confirmed to me by the California Independent System Operator – was fleeting and lasted only four seconds.

What is the real picture over several months or a year? For that, you’ll have to ignore the cheerleading reporters in the MSM and try to find some aggregated stats. Here are the figures from the California Energy Commission for the full year 2020. The total contribution of “renewables” to the electricity supply is given as 33.09%. Oh, but that includes 2.45% from “biomass”, 4.89% from “geothermal energy” and 1.39% from “small hydropower”. Take these out and you have a great 24.36% wind and sun. And since electricity only accounts for around 30% of final energy consumption, wind and sun only contribute around 8% to total energy consumption in California.

Over on the California Independent System Operator (“CAISO”) website, they provide a table of daily electricity production that dramatically illustrates the problem. California’s peak power demand is around 40 GW and generally occurs between 6:00 p.m. and 8:00 p.m. The majority of their “renewable” production comes from solar. Your current solar capacity delivers around 12 GW from around 9 a.m. to 5 p.m. on a sunny midsummer day like today – and nothing for the rest of the time, even when it is in peak use. In winter, the output from 10 a.m. to 4 p.m. is more like 8 GW, the rest of the time nothing. So far, almost nothing has stood in the way of energy storage on a grid scale. In the evening they start up the natural gas power plants and import electricity from Arizona and Nevada – mostly natural gas, nuclear power and coal. Almost 30% of California’s electricity comes from imports from neighboring states.

Read the full article here.

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On April 10, 2019, the world was presented with the first image of a black hole courtesy of the Event Horizon Telescope (EHT). Specifically, the image showed the supermassive black hole (SMBH) at the center of the super-giant elliptical galaxy known as M87 (also known as Virgo A). These powerful natural forces reside at the centers of most massive galaxies, which include the Milky Way (where the SMBH known as Sagittarius A * is located).

Using a technique known as Very Long Baseline Interferometry (VLBI), this image signaled the birth of a new era for astronomers to finally conduct detailed studies of these powerful forces of nature. Thanks to research by the EHT collaboration team during a six-hour observation period in 2017, astronomers are now receiving images of the core region of Centaurus A and the radio jet emanating from it.

The study describing their results, which was recently published in Nature Astronomy, was carried out by the EHT collaboration, which includes more than 300 researchers from Africa, Asia, Europe, North and South America. There were also researchers from the Max Planck Institute for Radio Astronomy, the Black Hole Initiative (BHI), the Yale Center for Astronomy and Astrophysics, the Princeton Center for Theoretical Science, the Flatiron Institute and several universities and research institutes.

Image of the Centaurus A galaxy combining optical, X-ray, and infrared data. Photo credit: Roentgen: NASA / CXC / SAO; Optical: Rolf Olsen; Infrared: NASA / JPL-Caltech

For decades, astronomers have known that SMBHs are at the heart of most massive galaxies, surrounded by massive rings of dust and gas. These rings are caused by the tremendous pull of the SMBHs, which accelerates the dust and gas to relativistic speeds (a fraction of the speed of light) and releases large amounts of electromagnetic energy (including radio waves).

This process causes galactic nuclei to become “active” – ​​also known as. an active galactic core (AGN) or quasar – where the core region outshines the galactic disk many times over. While matter at the edge of the black hole is accreted on its surface, part of the surrounding matter escapes shortly before it is captured in the form of relativistic jets – one of the most energetic properties in the known universe.

As they indicate in their study, data from the 2017 EHT observation campaign enabled the team to capture images that were ten times higher in frequency and sixteen times sharper in resolution. This was made possible by the resolving power of the EHTs, which results from eight radio observatories, which together result in a virtual telescope with an earth-sized aperture.

Centaurus A is over 13 million light years from the Milky Way and is the closest radio galaxy to us and (when recorded in radio wavelengths) one of the largest and brightest objects in the night sky. Using the same interferometry technique that was used to capture images of M87, Team Centaurus A was able to observe with incredibly sharp resolution at a wavelength of 1.3 mm.

Close-ups of the relativistic jet emanating from Centaurus A. Credit: M. Janssen, H. Falcke, M. Kadler, E. Ros, M. Wielgus et al.

Study co-author Heino Falcke, an EHT board member and professor of astrophysics at Radboud University, said in a NOVA press release:

“This enables us for the first time to see and study an extragalactic radio jet on smaller scales than light travels in a day. We see up close and personal how a monstrous gigantic jet shot down from a supermassive black hole is born …

“These data come from the same observation campaign that provided the famous image of the black hole in M87. The new results show that the EHT offers a treasure trove of data on the rich diversity of black holes and more to come. “

Previously, the task of monitoring Centaurus A at radio wavelengths was overseen by Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry (TANAMI), a multi-wavelength program comprised of nine radio telescopes on four continents. Since the mid-2000s, TANAMI has been investigating the core region of Centaurus A with VLBI at centimeter wavelengths as well as other relativistic jets and active galactic nuclei (AGN) in the southern sky.

Not only was the new image much higher in terms of resolution, it also showed features of Centaurus A that had never been seen before. For example, the EHT team found that Centaurus A is brighter around the edges than in the center, a phenomenon that has been seen on other jets but has never been as pronounced. These observations will feed into the attempts of astrophysicists to model the behavior of matter in the presence of SMBHs, which is still unclear.

Astrophysicists in particular are still trying to figure out how relativistic jets are launched, or how they can stretch over light years without spreading. “We found it difficult to explain using the same models we used for the M87,” said Sera Markoff, vice chair of the EHT Science Council and co-author of the study. “Something else has to happen, like spiral magnetic fields that give us new clues as to how to” squeeze “the jets.”

Thanks to the new EHT observations of the Centaurus A jet, it is believed that the launch point of the jets coincides with the likely location of the SMBH. On this basis, the research team predicts that future observations at even shorter wavelengths and resolutions could photograph the SMBH in the center of Centaurus A – similar to 2019 with the M87.

This will likely require space-based observations that will allow for more accurate baseline interferometry (which is free from atmospheric distortion). Ongoing study of this phenomenon, made possible thanks to arrays like the EHT, also allows astronomers to observe how the laws of physics work in the most extreme environments in the universe.

Further reading: NOVA, Natur

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Guest essay by Eric Worrall

Climate scientists have issued an updated climate emergency declaration, urging us to take them seriously this time.

World Scientists’ Warning of a Climate Emergency 2021 

William J Ripple,  Christopher Wolf,  Thomas M Newsome,  Jillian W Gregg, Timothy M Lenton,  Ignacio Palomo,  Jasper A J Eikelboom,  Beverly E Law,  Saleemul Huq, Philip B Duffy,  Johan Rockström

In 2019, Ripple and colleagues (2020) warned of untold suffering and declared a climate emergency together with more than 11,000 scientist signatories from 153 countries. They presented graphs of planetary vital signs indicating very troubling trends, along with little progress by humanity to address climate change. On the basis of these data and scientists’ moral obligation to “clearly warn humanity of any catastrophic threat,” they called for transformative change. Since the article’s publication, more than 2,800 additional scientists have signed that declaration of a climate emergency (see supplemental file S1 for the current signatory list); in addition, 1,990 jurisdictions in 34 countries have now formally declared or recognized a climate emergency (figure 1p). But, at the same time, there has been an unprecedented surge in climate-related disasters since 2019, including devastating flooding in South America and Southeast Asia, record shattering heat waves and wildfires in Australia and the Western United States, an extraordinary Atlantic hurricane season, and devastating cyclones in Africa, South Asia, and the West Pacific (see supplemental file S2 for attribution information). There is also mounting evidence that we are nearing or have already crossed tipping points associated with critical parts of the Earth system, including the West Antarctic and Greenland ice sheets, warm-water coral reefs, and the Amazon rainforest (supplemental file S2). Given these alarming developments, we need short, frequent, and easily accessible updates on the climate emergency.

Read more: https://academic.oup.com/bioscience/advance-article/doi/10.1093/biosci/biab079/6325731

There is no evidence I can see that this climate emergency will be any more significant than previous climate emergency declarations and tipping point warnings, dating back to the grandaddy of climate emergency declarations in 1989.

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