China launches two more Beidou GPS-type satellites

The new colonial movement: China today used its Long March 3B rocket to launch two more Beidou GPS-type satellites.

With this launch China has successfully matched its predicted number of launches for 2019, a number that it should exceed with several more launches scheduled before the end of the year.

The leaders in the 2019 launch race:

30 China
20 Russia
12 SpaceX
7 Europe (Arianespace)

China now leads the U.S. in the national rankings 30 to 25. These numbers should change later today, as SpaceX has a commercial launch scheduled.

New info on Long March 5 launch failures

An article in the English Chinese press today about the upcoming third launch of China’s Long March 5 rocket revealed some new information about the failures of that rocket during its first two test flights.

On its maiden mission in November 2016, the rocket failed to reach the speed required for the early phase of the flight; still, extra booster fuel burned in the final stage lifted its satellite cargo into orbit and allowed China to declare the trip a success.

In the second flight a few months later, though, the main engine died minutes after take-off, and the rocket plunged into the sea.

I have tried to read every iota of information released about the first two launches of the Long March 5 in order to figure out what went wrong during its second launch. At no time however had I ever come across any report that described any launch problems during its first flight. The Chinese always touted that first flight as a complete success, with no problems.

We now learn that the first stage during that first launch was under-powered, a problem that was not dealt with before the second launch, resulting in the complete failure of that second launch.

This is the typical behavior one sees in a government-run top-down program. Rather than bluntly address problems to fix them, even if it means someone will be embarrassed, management acts to protect itself, hiding problems so as to avoid blame. The result is always more failures.

As long as China’s economy is booming and providing its government with lots of cash for its space program, such problems can be papered over and even overcome. The second however that economy begins to falter, the program will stumble, the hidden problems acting like an avalanche to overwhelm everything.

Vector files for bankruptcy

Capitalism in space: On December 13 the smallsat rocket company Vector officially filed for bankruptcy, a precursor to having its assets sold off.

The company filed a voluntary petition for bankruptcy with the United States Bankruptcy Court for the District of Delaware, the state where the company was incorporated.

…Vector had been one of the leading companies in the small launch vehicle market until August, when the company said that a “significant change in financing” led it to pause operations and lay off nearly all of its more than 150 employees. Jim Cantrell, Vector’s chief executive, also left the company at the time. That announcement came just two days after the company won an Air Force launch contract.

According to industry sources familiar with the company, the August layoffs were triggered when one of the company’s major investors, venture fund Sequoia, withdrew its support for the company because of concerns about how the company was managed. That came as Vector was working on a new funding round, and Sequoia’s decision had a domino effect, causing other investors to back out. Sequoia didn’t respond to a request for comment in August about any role it played in Vector’s problems.

The company is currently being funded through “debtor in possession” financing from Lockheed Martin, according to a resolution by Vector’s board of directors included in the filing. Under a Nov. 20 agreement, Lockheed provided Vector with a $500,000 secured loan and proposed purchasing Vector’s assets associated with a satellite program called GalacticSky for no more than $2.5 million.

While companies sometimes recover from this situation, in this case Vector looks quite dead, for good. A real tragedy, but part of the reality of capitalism. The competition fuels innovation and success, but carries great risk and the real possibility of failure.

North magnetic pole continues its drift

The uncertainty of science: The newest 2020 version of the World Magnetic Model, released on December 10, 2019, shows that the north magnetic pole is continuing its unprecedented drift eastward and away from the Canadian Arctic.

A new and updated version of the WMM is released every five years. The latest WMM2020 model will extend to 2025.

Since Earth’s magnetic field is created by its moving, molten iron core, its poles aren’t stationary and they wander independently of each other. Since its first formal discovery in 1831, the north magnetic pole has traveled around 1,400 miles (2,250 km). This wandering has been generally quite slow, allowing scientists to keep track of its position fairly easily. Since the turn of the century, this speed has increased.

The WMM2020 forecasts that the northern magnetic pole will continue drifting toward Russia, although at a slowly decreasing speed—down to about 40 km per year compared to the average speed of 55 km over the past twenty years.

Though we know the magnetic field is produced by the magnetism related to the Earth’s molten iron core, scientists do not have a solid understanding of the details, including why the drift of the pole has accelerated this century as well as shifted eastward.

The importance of small telescopes to science and civilization

The main cluster of telescopes, on Mount Lemmon
Largest cluster of telescopes on Mount Lemmon, six visible with three just out of view.

On December 11, 2019 I was kindly given a personal tour by Alan Strauss, director of the Mount Lemmon Sky Center, of the telescopes located on the mountaintops of the Santa Catalina Mountains overlooking Tucson. Strauss runs the educational outreach program for the University of Arizona astronomy department and the Steward Observatory, both of which operate the mountaintop facility.

The telescopes, numbering almost a dozen, are in two groups, two telescopes on the peak of Mount Bigelow and the rest clustered on the higher peak of Mount Lemmon. None are very gigantic by today’s standards, with their primary mirrors ranging in size from 20- to 61-inches. For comparison, the largest operating telescope in the world on the Canary Islands is 409 inches across. Hubble has a 94-inch mirror. And the new giant telescopes under design or being built have mirrors ranging from 842 inches (Giant Magellan) to 1,654 inches (European Extremely Large Telescope).

Thus, the small telescopes in the Santa Catalinas generally don’t make the news. They are considered passe and out-of-date, not capable of doing the kind of cutting edge astronomy that all the coolest astronomers hunger for.

Yet, without them, we likely would not have future astronomers. » Read more

Scientists reject discovery of biggest known black hole

The uncertainty of science: In three new papers published this week astronomers have found that the announced discovery in early December of the biggest super-massive black hole ever found, 70 times the mass of the Sun, does not hold up.

In a recent study (a peer-reviewed study published Nov. 27), a team of scientists reported the discovery of the binary system LB-1, which contains a star and, according to the findings, a black hole companion 70 times the mass of our sun. This was major news, a stellar-mass black holes (black holes formed by the gravitational collapse of a star) are typically less than half that massive. But while the study, led by Jifeng Liu, of the National Astronomical Observatory of China (NAOC) of the Chinese Academy of Sciences, was exciting, it was also wrong.

Three new papers came out this week that reexamined the findings from Liu’s study, and these studies say that LB-1’s black hole isn’t actually all that massive.

The new papers find that a closer look at the data finds that it wasn’t doing what the initial researchers thought.

Maven makes first map of Mars’ high altitude winds

High altitude wind patterns on Mars

Scientists using the Martian orbiter Maven have produced the first global map of the high altitude wind circulation of Mars.

The measurements of winds that were recently mapped above Mars were found at an altitude range of about 140-240 kilometers (85-150 miles) above the planet’s surface.

The wind data has been gathered by the Neutral Gas and Ion Mass Spectrometer (NGIMS). NGIMS’ original purpose was to determine the structure and composition of the Martian atmosphere by measuring in it the amounts of ions (electrically charged particles) and gases. However, although it was not originally designed to do so, in April 2016, the MAVEN team began using NGIMS to observe horizontal winds. Pausing normal collection of data, scientists on Earth programmed the instrument to nod back and forth so that it could detect the direction of winds along its track.

By combining data from many tracks as MAVEN orbits Mars, scientists slowly built up a map of wind behavior. This led to a startling discovery: the wind patterns actually correlated with the Martian topography below.

They have found that even at this high altitude the winds shift around the high volcanoes of the Tharsis Bulge.

To my eye, the wind pattern seen in the image, taken from the video at the link, is remarkably similar to the global wind patterns found on Venus, forming a widening V-pattern moving from east to west. Though the two are vastly different, the similarity is quite intriguing.

Rocket Lab opens Wallops Island launchpad

Capitalism in space: Rocket Lab yesterday officially cut the ribbon on its first U.S.-based launchpad at Wallops Island, Virginia.

Rocket Lab aims to launch up to 12 missions a year from LC-2 [Wallops], about one a month, once flights begin in 2020. The first mission will launch in spring 2020 to deliver the U.S. Air Force’s Space Test Program 27RM (STP-27RM) mission into orbit. That mission will launch a microsatellite called Monolith to see if small satellites can effectively carry “large aperture” space weather payloads, said Lt. Col. Meagan Thrush, program element monitor for space launch and control for the Air Force, in a news conference here today.

The company has a similar launch rate capability at its New Zealand launch site. Thus, if they have the customers, Rocket Lab now has the ability to launch upwards of 24 times next year.

Interacting galaxies

Interacting galaxies
Click for full image.

Astronomers using the 8-meter Gemini Telescope on Mauna Kea today released a new image of the Heron galaxy, showing its interaction with a nearby neighbor.

The new image captures the slow and intimate dance of a pair of galaxies some 160 million light-years distant and reveals the sparkle of subsequent star formation fueled by the pair’s interactions.

The two galaxies, astronomers have concluded, have already “collided” at least once. However, galactic collisions can be a lengthy process of successive gravitational encounters, which over time can morph the galaxies into exotic, yet unrecognizable forms. These galaxies, as in all galactic collisions, are engaged in a ghostly dance as the distances between the stars in each galaxy preclude actual stellar collisions and their overall shapes are deformed only by each galaxy’s gravity.

One byproduct of the turbulence caused by the interaction is the coalescence of hydrogen gas into regions of star formation. In this image, these stellar nurseries are revealed in the form of the reddish clumps scattered in a ring-like fashion in the larger galaxy (and a few in the smaller galaxy). Also visible is a dusty ring that is seen in silhouette against the backdrop of the larger galaxy. A similar ring structure is seen in this previous image from the Gemini Observatory, likely the result of another interacting galactic pair.

New storm spotted at Jupiter’s south pole

New cyclone at Jupiter's south pole
Click for full image.

New images from Juno have revealed the formation of a new Texas-sized cyclone joining the circle of storms around Jupiter’s south pole.

In the infrared Juno image to the right, the new storm is the small bright cyclone in the lower right.

[D]uring Juno’s 22nd science pass [on November 3], a new, smaller cyclone churned to life and joined the fray. “Data from Juno’s Jovian Infrared Auroral Mapper [JIRAM] instrument indicates we went from a pentagon of cyclones surrounding one at the center to a hexagonal arrangement,” said Alessandro Mura, a Juno co-investigator at the National Institute for Astrophysics in Rome. “This new addition is smaller in stature than its six more established cyclonic brothers: It’s about the size of Texas. Maybe JIRAM data from future flybys will show the cyclone growing to the same size as its neighbors.”

Probing the weather layer down to 30 to 45 miles (50 to 70 kilometers) below Jupiter’s cloud tops, JIRAM captures infrared light emerging from deep inside Jupiter. Its data indicate wind speeds of the new cyclone average 225 mph (362 kph) – comparable to the velocity found in its six more established polar colleagues.

Because of Juno’s orbit we do not get continuous views of the gas giant’s cloud-tops, so we can’t see the moment-by-moment evolution of these storms, which makes it impossible to obtain a full understanding of their formation or disappearance. Even then it will likely take centuries of observations to even begin to get a fuller understanding of the meteorology of Jupiter.

Major victory for Boris Johnson, Tories, and Brexit

A victory for democracy: In the elections today in the United Kingdom it appears at this moment that the conservative Tories under Boris Johnson, running under a platform to quickly enforce the public’s vote three years ago to leave the European Union, have won the biggest majority since the 1980s under Margaret Thatcher.

As is typical in the modern journalist field, these results are also much more favorable to the conservatives than all the polls, which had called for a much closer result. The result is also a major rejection of Great Britain’s leftist and increasingly anti-Semitic Labor Party under Jeremy Corbyn.

Most important, the victory for Johnson is also a vindication of his strong position that he and Great Britain’s politicians had a responsibility to respect the voters’ choice three years ago to exit the European Union, and the effort by politicians to nullify that vote was a direct attack on democracy. The voters have clearly shown their contempt for that nullification effort, and have said so forcefully at the polls.

My immediate thought, from an American perspective: If only the American voters were as willing to make such a forceful statement. Our Democratic Party has been acting as bad and as anti-democratic as the politicians in the UK these past three years. It is long past time for a major political house-cleaning in Washington.

So far, the American voters have shown no inclination to do this, however, and in fact in the 2018 election did the exact opposite, rewarding the corrupt Democratic Party with more power by giving them control of the House. The result has been this ludicrous impeachment effort by the Democrats that is blatantly an effort to nullify the 2016 presidential election. They have no grounds for impeachment and the removal of Donald Trump, other than the fact that they don’t like him and that he beat them in a fair election.

They should be punished in the same way. Will the American voters do it? So far I remain pessimistic. I also pray every day that my pessimism turns out to be wrong.

New Hubble images of Comet 2I/Borisov

Comet 2I/Borisov taken by Hubble prior to and at its closest approach to Sun
Click for full image.

Scientists today released new images taken by the Hubble Space Telescope of the interstellar object Comet 2I/Borisov. The image on the left was taken prior to the comet’s closest approach to the Sun, while the image on the right was taken during that closest approach. The vertical smeared object to the left in the earlier image is a galaxy that happened to be in the field of view. The blue color of both images is a false color to bring out details.

“Hubble gives us the best upper limit of the size of comet Borisov’s nucleus, which is the really important part of the comet,” said David Jewitt, a UCLA professor of planetary science and astronomy, whose team has captured the best and sharpest look at this first confirmed interstellar comet. “Surprisingly, our Hubble images show that its nucleus is more than 15 times smaller than earlier investigations suggested it might be. Our Hubble images show that the radius is smaller than half-a-kilometer. Knowing the size is potentially useful for beginning to estimate how common such objects may be in the solar system and our galaxy. Borisov is the first known interstellar comet, and we would like to learn how many others there are.”

The first image was taken from a distance of 203 million miles, while the second was taken from 185 million miles. Expect more images in late December, when the comet makes its closest approach to Earth at a distance of 180 million miles.

OSIRIS-REx team picks primary sample site

Four candidate landing sites
Click for full image.

The OSIRIS-REx science team has picked the site they have dubbed Nightingale as the primary landing site where they will attempt to obtain a sample from the asteroid Bennu in the summer of 2020. The back-up site is Osprey at the equator.

I have embedded the replay of the NASA live stream of the press event below the fold. The first 21 minutes of the video are an overview of the mission, leading up to the announcement by Dante Lauretta, OSIRIS-REx’s principal investigator. He notes then that the site “does have some hazards” but they chose it for its “scientific value.” While its higher latitude location has some advantages, it also makes it more difficult for landing. The one large boulder there, which Lauretta calls “Mt Doom,” also carries risk for the touch-and-go operations.

The back-up site, Osprey, is on the equator with less hazards, but will present more problems obtaining the tiny-sized particles the sample grab equipment was designed to get.

Not that this matters, but if I have been in a betting pool I would have won, since Nightingale has been my guess for which site they’d pick since early November.
» Read more

Buyer of Stratolaunch revealed though unconfirmed

A news story today at Geekwire has revealed, based on business filings in Washington and California, the new owner of the company Stratolaunch.

Filings with regulators in California and Washington show that a new LLC business, also called Stratolaunch, was incorporated in late October, at Stratolaunch’s existing offices in Seattle and Mojave, Calif. The new Stratolaunch’s executive vice president is named as Michael Palmer, Cerberus’ managing director.

Private-equity firms typically replace existing managers as a prelude to realigning businesses they buy, which can involve firing, automation and offshoring. However, it appears that Jean Floyd, Stratolaunch’s president and CEO since 2015, remains in his roles for now.

It appears the new owners, who did not confirm the Geekwire story, are now marketing the huge Roc airplane as a launch platform for hypersonic test flights rather than orbital satellites.

New Shepard completes another test flight

Capitalism in space: Blue Origin today successfully completed its sixth unmanned test flight (a new record) of its third New Shepard reusable suborbital spacecraft, the twelfth flight total and the ninth to carry commercial payloads.

The capsule reached an altitude of about 342,000 feet elevation.

Blue Origin’s success here is commendable. I just wish their launch pace was faster. At the pace they are setting I am beginning to think that SpaceX will be flying people to the Moon on Starship before Blue Origin flies its first commercial tourist suborbital flight.

I have embedded the video of the flight below the fold.
» Read more

A new map of the water ice on Mars

Annotated water ice map of Mars
Click for full resolution image.

In a new science paper planetary scientists have produced a new global map of the water ice of Mars, based on data from Mars Reconnaissance Orbiter (MRO) and Mars Odyssey.

The image above is a lower resolution version of that map, annotated by me. The black areas are regions covered with a thicker layer of dust, so no good data was obtained. As you go from red to green to blue to purple the ice is thought to be closer to the surface, with the depth as small as an inch in the dark purple areas. The white rectangular represents the region best for human settlement, as it has ice near the surface and is at lower latitudes.

The red box indicates the location in Arcadia Planitia that is SpaceX’s candidate landing zone for Starship. Based on this new water ice map it appears that SpaceX has chosen very well. And the scientists who wrote this paper agree, as noted in the press release: “A large portion of a region called Arcadia Planitia is the most tempting target in the northern hemisphere.”

The map also confirms the existence of the 30 to 60 degree latitude bands where scientists believe a lot of buried glaciers exist. Both bands are both very evident in this new map.

To provide some further context, below is a global map of Mars labeled to show its major geographic features as well as the locations of all previous and upcoming landers/rovers, rearranged to match the water ice map above.
» Read more

Russia and India launch satellites

Two launches since yesterday. First, Russia used its Soyuz-2 rocket to place another GPS-type Glonass satellite into orbit. This was Russia’s 20th successful launch in 2019, the first time that country has hit that number since 2015.

Then India used its PSLV rocket to launch a military radar reconnaissance satellite.

The leaders in the 2019 launch race:

29 China
20 Russia
12 SpaceX
7 Europe (Arianespace)
6 Rocket Lab
6 India

China remains the leader in the national rankings, 29 to 25 over the U.S.

How the Mars2020 rover differs from Curiosity

A JPL press release today outlines some of the main engineering differences between Curiosity, the rover that has been exploring Gale Crater for the past fifteen years, and Mars2020, the unnamed rover that will be launched in July 2020 to explore Jezero Crater

One of the major the engineering improvements, based on what was learned with Curiosity, are the Mars2020 wheels:

Curiosity has prepared Mars 2020’s team for “off-roading” on the Red Planet. When holes began appearing in the veteran rover’s aluminum wheels, engineers realized that sharp rocks cemented on the Martian surface exert more pressure on the wheels than expected. Careful drive planning, along with a software upgrade, will keep them in shape for the rest of Curiosity’s journey up Mount Sharp.

While Mars 2020’s wheels are made from the same materials, they’re slightly bigger and narrower, with skins that are almost a millimeter thicker. Instead of Curiosity’s chevron-pattern treads, or grousers, Mars 2020 has straighter ones and twice as many per wheel (48 versus 24). Extensive testing in JPL’s Mars Yard has shown these treads better withstand the pressure from sharp rocks but work just as well on sand.

The computer and software has also been upgraded to speed daily operations. In addition, the new rover will have 23 cameras, six more than Curiosity, all of which will be capable of producing color images. And most important, the drill will be larger and will drill cores for obtaining samples that will be stored for possible return by a later mission.

The landing is set for February 18, 2021. If all goes well this rover will be exploring the Martian surface well in to the 2030s.

Morgan Stanley recommends buying Virgin Galactic stock

Capitalism in space: A report yesterday by Morgan Stanley recommended the purchase of Virgin Galactic stock because of its claim that it might repurpose its SpaceShipTwo suborbital spacecraft from space tourism to point-to-point transportation on Earth.

Morgan Stanley began coverage of Virgin Galactic’s stock on Monday with an overweight rating, saying the space tourism company’s shares will soar as it proves out a long-term plan of flying people around the world at hypersonic speeds. “A viable space tourism business is what you pay for today … but a chance to disrupt the multi-trillion-dollar airline [total addressable market] is what is really likely to drive the upside,” Morgan Stanley analyst Adam Jonas wrote in a note to investors.

…Morgan Stanley’s price target of $22 a share represents a 203% increase from Virgin Galactic’s current levels. The company outlined a three phase plan to investors during its roadshow earlier this year. While Morgan Stanley gave a $10 a share valuation to Virgin Galactic’s space tourism business, phases one and two of its plan, the firm sees $12 a share in value from phase three: Hypersonic point-to-point air travel.

The report caused the space company’s lagging stock to surge yesterday, though its value today ($9.41) remains well below its opening price ($12.53).

Personally I think anyone who takes Morgan Stanley’s advice is a fool. Virgin Galactic has spent fifteen years trying to develop this suborbital spacecraft, and has still not flown any customers. Moreover, the design is underpowered, which means I have serious doubts it could be used for any point-to-point transportation. To make that happen will require a complete redesign.

This recommendation by Morgan Stanley also suggests that this is not my investment firm of choice. The analysis here seems very poor and somewhat ignorant of the technology involved, and suggests instead that it was aimed merely to cause a jump in the price so that some of Morgan Stanley’s customers could get rid of their already-purchased stock without too much loss.

Congress approves establishment of Space Force

In a deal where the Trump administration agreed to a Democratic Party demand that all military personnel be given twelve weeks of paid parental leave, Congress has approved the formation of a new branch of the military dubbed the U.S. Space Force.

In a Dec. 6 deal, the White House agreed to grant 12 weeks of paid parental leave to all federal workers in exchange for the Space Force authorization. The parental leave provision was a top priority for Democrats while the White House has been insistent that any deal should include language to authorize the Space Force.

The House is expected to vote on the compromise bill on Dec. 11. The Senate will take it up at a later date.

The NDAA provides the Secretary of the Air Force with the authority to transfer Air Force personnel to the newly established Space Force. But it does not approve the hiring of new people. The Air Force Space Command is redesignated as the U.S. Space Force. “To minimize cost and bureaucracy, the Space Force will require no additional billets and remains with the President’s budget request,” says the report. The request includes $72.4 million to stand up the headquarters. [emphasis mine]

It appears that initially the Space Force will operate under the auspices of the Air Force, but only during a transitional period.

The highlighted words suggest that Congress has managed, at least so far, in making this new agency mostly a rearrangement of personnel, something that makes sense. Military space operations need to be consolidated into one command structure.

We shall see however if Congress (and future presidents) can resist allowing this new bureaucracy to grow. I have my doubts, which if proven true will defeat the entire purpose for doing this. For example, while generally avoiding the hiring of many new people, the legislation also creates three new administrative posts, all of which I guarantee will eventually demand their own bureaucracies.

ESA hires private company to remove space junk

Capitalism in space: The European Space Agency has hired the private company ClearSpace to fly an unmanned mission aimed at de-orbiting a large no-longer-needed launch component of its Vega rocket.

The European Space Agency signed a debris-removal contract with Swiss startup ClearSpace tasking the company with deorbiting a substantial piece of a Vega rocket left in orbit in 2013.

The mission, dubbed ClearSpace-1, is slated to launch in 2025 to capture and deorbit a 100-kilogram Vespa payload adapter an Arianespace Vega left in orbit after deploying ESA’s Proba-V remote-sensing satellite.

ClearSpace will lead a consortium of European companies in building a spacecraft equipped with four robotic arms to capture debris and drag it into Earth’s atmosphere.

The real importance of this contract is its nature. ESA is not taking the lead in designing or building the robot to do this work. Instead, it is acting merely as a customer, hiring ClearSpace to develop and build it. Afterward the robot design will belong to ClearSpace, which will then be able to sell that design for further space junk removal contracts.

[Luc Piguet, co-founder and chief executive of ClearSpace] said that while this first mission will destroy both the debris and the servicer spacecraft, future plans call for servicers that could deorbit multiple objects without also destroying themselves.

It seems that the ESA is following the recommendations I put forth in Capitalism in space, shifting power and ownership of its space missions from the agency to the private sector. This is excellent news.

New Shepard test flight delayed to tomorrow

The sixth flight of Blue Origin’s second New Shepard reusable suborbital capsule has been delayed today until tomorrow due to weather.

As they have done on the last few flights they are launching a number of commercial payloads, including winning high school art chosen as part of a contest sponsored by both Blue Origin and the music band OK Go.

I have embedded below the fold the live stream for tomorrow’s launch, set to go live at around 8 am (Eastern).
» Read more

Sunspot update Nov 2019: The longest flatline in centuries

The Sun is now in what appears to be the longest stretch ever recorded, since the 11-year solar sunspot cycle reactivated in the 1700s after the last grand minimum, of sunspot inactivity. This record-setting dearth of practically no sunspots has now stretched to six months in a row.

On December 8 NOAA released its November update of its graph showing the long term sunspot activity of the Sun. As I have done now every month since this webpage began in 2011, I have posted it below, with annotations:

November 2019 sunspot activity
The graph above has been modified to show the predictions of the solar science community for the previous solar maximum. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction, extended in November 2018 four years into the future.

In November the Sun saw two official sunspots (here and here) and one active area that never received an official sunspot number, with two of these three weak events having a polarity linking them to the next solar maximum.
» Read more

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