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A Solar Minimum Is Coming

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Because we are normal people living in normal times, normal things are happening. Like news tabloids reporting that the Sun is in “lockdown”, and that Earth is doomed to crazy weather famine and… earthquakes, for some reason.

Well, you can relax. Nothing the Sun is currently doing is going to create freezing weather, famine, or earthquakes. While humans are experiencing things that are decidedly not okay, the Sun is doing nothing unusual whatsoever.

What could be happening is a very normal period in the Sun’s 11-year cycle; it’s called solar minimum. And it’s nothing to be afraid of – if you’re reading this, chances are you’ve already lived through several solar minimums without even noticing.

Currently, we’re in solar cycle 24. We don’t know precisely when the next solar minimum will occur, but we can broadly predict it. Back in 2017, NASA noted that solar minimum was expected in 2019-2020.

In December of last year, the NOAA’s Solar Cycle 25 Prediction Panel narrowed it down further, stating that “solar minimum between cycles 24 and 25 will occur in April, 2020 (+/- 6 months).”

So, we’re either going through solar minimum already, or are just about to do so. Here’s what that actually entails.

The solar cycle is based on the Sun’s magnetic field, which flips around every 11 years, with its north and south magnetic poles switching places. It’s not known what drives these cycles – recent research suggests it has to do with an 11.07-year planetary alignment – but the poles switch when the magnetic field is at its weakest, also known as solar minimum.

Because the Sun’s magnetic field controls solar activity – sunspots, coronal mass ejections and solar flares – the cycle is detectable to us as that activity changes. During solar minimum, there are, well, minimal sunspots and flares.

This gradually changes as the Sun ramps up to solar maximum. The magnetic field grows stronger, and sunspot and flare activity increases, before subsiding again for the next solar minimum.

The solar cycles aren’t generally noticeable here on Earth. We may see more aurora activity during solar maximum, since auroras are generated by solar activity. Increased solar activity can also affect radio communications, and navigation satellites. People closely observing the Sun will see more sunspots during solar maximum.

At solar minimum, solar ultraviolet radiation decreases, but the effect of this primarily hits the stratosphere and higher altitudes. It causes Earth’s atmosphere to shrink slightly, which reduces drag on satellites. Conversely, the increase in UV radiation during solar maximum contributes to rainfall, but the effect on temperature is negligible.

There is also an increase in galactic cosmic rays from sources such as supernovae during solar minimum. Earth’s atmosphere protects us surface-dwellers from this radiation, which can increase the risk of cancer, but at higher altitudes the radiation does pose an additional hazard to astronauts.

“During solar minimum, the Sun’s magnetic field weakens and provides less shielding from these cosmic rays,” said astronomer Dean Pesnell of NASA’s Goddard Space Flight Center in 2017. “This can pose an increased threat to astronauts traveling through space.”

The link to dropping temperatures, earthquakes and famine is tenuous at best. A few days ago, a tabloid called, uh, The Sun cited unnamed “NASA scientists” fearing a repeat of an event known as the Dalton Minimum.

This occurred around the early 19th century, which saw an extreme period in Earth’s recorded history, centred around 1816 – the Year Without a Summer. Temperatures dropped, crops failed, and many people around the world starved to death, or died from the cold.

Except that had nothing to do with the Sun’s activity. All those problems were caused by the colossal 1815 eruption of Mount Tambora in Indonesia. In addition, a 2013 paper found no link between solar activity and earthquakes.

The most recent solar cycle was relatively quiet, leading to a lot of fearmongering over an impending Grand Solar Minimum, a longer period of time spanning several cycles where even the maximums are subdued. Reports suggested global temperatures would plummet, producing a mini ice age. NASA gave this idea a sound drubbing earlier this year.

“The warming caused by the greenhouse gas emissions from the human burning of fossil fuels is six times greater than the possible decades-long cooling from a prolonged Grand Solar Minimum,” wrote the NASA Global Climate Change team in February.

“Even if a Grand Solar Minimum were to last a century, global temperatures would continue to warm. Because more factors than just variations in the Sun’s output change global temperatures on Earth, the most dominant of those today being the warming coming from human-induced greenhouse gas emissions.”

Some scientists have drawn a connection between solar minimum and volcanic activity, but it’s weak and different papers don’t agree on the periodicity. But we probably don’t have to worry about that, either. The Sun is significantly more active than it was during the Dalton Minimum, which saw very low sunspot activity from around 1790 to 1830.

And, although cycle 24 was smaller than the previous few cycles, those cycles were unusually strong. Cycle 24 marked a return to a more normal activity level.

So, the solar minimum we’re about to enter doesn’t look particularly unusual, according to the NOAA and NASA, and we can expect a similar intensity to the previous cycle, they noted in their prediction.

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After 45 years, NASA's Voyager 1 space probe encounters mystery issue – CP24 Toronto's Breaking News

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(CNN) — The Voyager 1 probe is still exploring interstellar space 45 years after launching, but it has encountered an issue that mystifies the spacecraft’s team on Earth.

Voyager 1 continues to operate well, despite its advanced age and 14.5 billion-mile distance (23.3 billion kilometers) from Earth. And it can receive and execute commands sent from NASA, as well as gather and send back science data.

But the readouts from the attitude articulation and control system, which control the spacecraft’s orientation in space, don’t match up with what Voyager is actually doing. The attitude articulation and control system, or AACS, ensures that the probe’s high-gain antenna remains pointed at Earth so Voyager can send data back to NASA.

Due to Voyager’s interstellar location, it takes light 20 hours and 33 minutes to travel one way, so the call and response of one message between NASA and Voyager takes two days.

So far, the Voyager team believes the AACS is still working, but the instrument’s data readouts seem random or impossible. The system issue hasn’t triggered anything to put the spacecraft into “safe mode” so far. That’s when only essential operations occur so engineers can diagnose an issue that would put the spacecraft at risk.

And Voyager’s signal is as strong as ever, meaning the antenna is still pointed to Earth. The team is trying to determine if this incorrect data is coming directly from this instrument or if another system is causing it.

“Until the nature of the issue is better understood, the team cannot anticipate whether this might affect how long the spacecraft can collect and transmit science data,” according to a NASA release.

“A mystery like this is sort of par for the course at this stage of the Voyager mission,” said Suzanne Dodd, project manager for Voyager 1 and 2 at NASA’s Jet Propulsion Laboratory in Pasadena, California, in a statement.

“The spacecraft are both almost 45 years old, which is far beyond what the mission planners anticipated. We’re also in interstellar space — a high-radiation environment that no spacecraft have flown in before. So there are some big challenges for the engineering team. But I think if there’s a way to solve this issue with the AACS, our team will find it.”

If the team doesn’t determine the source of the issue, they may just adapt to it, Dodd said. Or if they can find it, the issue may be solved by making a software change or relying on a redundant hardware system.

Voyager has already relied on backup systems to last as long as it has. In 2017, the probe fired thrusters that were used during its initial planetary encounters during the 1970s — and they still worked after remaining unused for 37 years.

The aging probes produce very little power per year, so subsystems and heaters have been turned off over the years so that critical systems and science instruments can keep operating.

Voyager 2, a twin spacecraft, continues to operate well in interstellar space 12.1 billion miles (19.5 billion kilometers) from Earth. By comparison, Neptune, the farthest planet from Earth, is, at most, only 2.9 billion miles away. Both probes were launched in 1977 and have far exceeded their original purpose to fly by planets.

Now, they have become the only two spacecraft to gather data from interstellar space and provide insights about the heliosphere, or the bubble created by the sun that extends beyond the planets in our solar system.

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Boeing's Starliner ready to launch to space station on 2nd test flight – CBC.ca

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Boeing’s new Starliner capsule was set for launch on Thursday on a do-over uncrewed test flight to the International Space Station, aiming to deliver the company a much-needed success after two years of delays and costly engineering setbacks.

The gumdrop-shaped CST-100 Starliner was scheduled for liftoff at 6:54 p.m. ET from the Cape Canaveral Space Force Station in Florida, carried atop an Atlas V rocket furnished by the Boeing-Lockheed Martin joint venture United Launch Alliance (ULA).

ULA said Wednesday evening forecasts called for a 70 per cent chance of favourable weather conditions for an on-time launch.

If all goes as planned, the capsule will arrive at the space station about 24 hours later, docking with the research outpost orbiting some 400 kilometres above Earth at 7:10 p.m. ET on Friday.

The Boeing craft is to spend four to five days attached to the space station before undocking and flying back to Earth, with a parachute landing cushioned by airbags on the desert floor of White Sands, New Mexico.

A successful mission will move the long-delayed Starliner a major step closer to providing NASA with a second reliable means of ferrying astronauts to and from the International Space Station (ISS).

Since resuming crewed flights to orbit from American soil in 2020, nine years after the space shuttle program ended, the U.S. space agency has had to rely solely on the Falcon 9 rockets and Crew Dragon capsules flown by Elon Musk’s company SpaceX.

Payload and model passenger

The Starliner will not be flying to orbit empty. The capsule will carry a research mannequin to collect data on crew cabin conditions during the journey, plus 500 pounds of cargo for delivery to the space station’s crew — three NASA astronauts, a European Space Agency astronaut from Italy and three Russian cosmonauts.

Two of the U.S. astronauts will be tasked with boarding the capsule during Starliner’s stay to take measurements of its interior environment and unload the supplies.

Thursday’s launch marks a repeat of a 2019 test mission that failed to achieve a successful rendezvous with the space station because of a flight-software malfunction. Subsequent problems with Starliner’s propulsion system, supplied by Aerojet Rocketdyne, led Boeing to scrub an attempt to launch the capsule last summer.

NASA astronauts Suni Williams, left, Barry (Butch) Wilmore, centre, and Mike Fincke, right, watch as an Atlas V rocket with Starliner spacecraft aboard is rolled out to the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test-2 (OFT-2) mission. (NASA/Joel Kowsky)

The spacecraft remained grounded for nine more months while the two companies sparred over what caused its fuel valves to stick shut and which firm was responsible for fixing them.

Boeing says it has since resolved the glitch with a temporary workaround and plans to redesign the propulsion system’s fuel valves system after this week’s flight.

Starliner was developed with a $4.5 billion US fixed-price NASA contract to provide the U.S. space agency a second avenue to low-Earth orbit, along with SpaceX, and has proven costly to Boeing.

Delays and engineering setbacks with Starliner have led the aerospace giant to take $595 million US in charges since the capsule’s 2019 failure, even as the company strives to climb out of successive crises in its jetliner business and its space-defence unit.

If the second uncrewed trip to orbit succeeds, Starliner could fly its first team of astronauts in the fall, though NASA officials caution that time frame could get pushed back.

NASA astronauts Butch Wilmore and Mike Fincke had been designated to fly Starliner’s maiden crewed mission. But NASA officials, reluctant to tie down two astronauts to a flight whose launch date is uncertain, said Wednesday the mission could end up carrying at least two of any of the four astronauts now training to test-fly Starliner.

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Dusty demise for NASA Mars lander in July; power dwindling – CGTN

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A NASA spacecraft on Mars is headed for a dusty demise. 

The InSight lander is losing power because of all the dust on its solar panels. NASA said Tuesday it will keep using the spacecraft’s seismometer to register marsquakes until the power peters out, likely in July. Then flight controllers will monitor InSight until the end of this year, before calling everything off. 

“There really hasn’t been too much doom and gloom on the team. We’re really still focused on operating the spacecraft,” said Jet Propulsion Laboratory’s Bruce Banerdt, the principal scientist. 

Since landing on Mars in 2018, InSight has detected more than 1,300 marsquakes; the biggest one, a magnitude 5, occurred two weeks ago. 

It will be NASA’s second Mars lander lost to dust: A global dust storm took out Opportunity in 2018. In InSight’s case, it’s been a gradual gathering of dust, especially over the past year.

NASA’s two other functioning spacecraft on the Martian surface – rovers Curiosity and Perseverance – are still going strong thanks to nuclear power. The space agency may rethink solar power in the future for Mars, said planetary science director Lori Glaze, or at least experiment with new panel-clearing tech or aim for the less-stormy seasons.

InSight currently is generating one-tenth of the power from the sun that it did upon arrival. Deputy project manager Kathya Zamora Garcia said the lander initially had enough power to run an electric oven for one hour and 40 minutes; now it’s down to 10 minutes max. 

The InSight team had anticipated this much dust buildup, but hoped a gust of wind or dust devil might clean off the solar panels. That has yet to happen, despite several thousand whirlwinds coming close. 

“None of them have quite hit us dead-on yet enough to blow the dust off the panels,” Banerdt told reporters. 

Another science instrument, dubbed the mole, was supposed to burrow 16 feet (5 meters) underground to measure the internal temperature of Mars. But the German digger never got deeper than a couple of feet (a half-meter) because of the unexpected composition of the red dirt, and it finally was declared dead at the beginning of last year.

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