The sun reaches peak solar energy

Scientists are expecting to see more solar storms now that the sun has reached the peak of its 11-year solar cycle. Let's go live to ANU astrophysicist and cosmologist, Dr. Brad Tucker. Brad, thanks for your time. What happens at this phase, this part of the 11-year sun cycle? Yeah, so during the 11 years, the sun essentially flips its magnetic pole. So on Earth, we have a north and south pole. The sun has the same thing, but over 11 years, this reverse happens. And as this reverse happens, you get the most energy flowing through, charging really the atmosphere or the photosphere, the gas of the sun. And when that does, the sun does these eruptions, these little blips that you're kind of seeing on the surface of your screen now. And on the surface of the sun, you get all of these pockets. So it's not just one area that does an eruption, it's multiple areas that do an eruption. So during the peak solar cycle, you're not just having bigger eruptions at an individual time, you're having more of them and more frequent. And as that energy, as that gas leaves the sun, it travels through space and sometimes hits the Earth. And what sort of implications are there, Brad? I heard you describe them earlier as solar burps. What happens here for, say, satellites and things like that? Because it really is a burp of gas from the sun. And when the gas eventually hits our Earth, sometimes it produces amazing things like the aurora. So this gas, this plasma, is electrically charged. And when it hits our own atmosphere, it excites our own atmosphere's gas. So it's like a neon sign. The charge comes into the gas in our atmosphere and causes the gas to glow. So it produces the aurora, those purple, green, and reds that we've been seeing a lot of. So during the solar cycle peak, we get more aurora on Earth and the aurora are stronger, which is why we've had large parts of Australia much further than Tasmania seeing them in the past few months. But as you said, with satellites, that energy also hits our satellites. So it can actually damage them. It can cause circuits to short circuit. It can cause electrical interference. It can actually cause extra radiation damaging equipment. So then the satellite can either be damaged or turn off completely, turning it into space junk. And that poses a whole nother risk. It also changes the orbit of satellites. So our atmosphere's density actually changes. And therefore, the way the satellites move around the Earth slightly changes and they then need to correct and change their path. So all sorts of flow on effects from this. Are there any implications for things like SpaceX missions or say the ISS, the International Space Station? So very much so. We worry about that extra radiation and energy hitting people. So that's always a risk on the astronauts on board. As you said, also with SpaceX missions, it also has to be planned for satellite launches. So when satellites are launched by a rocket, you plan for a certain angle and speed. But if the density of the nature of Earth's atmosphere has changed because one of these storms, you may not get enough off essentially to get out. It can actually fall back to Earth, never making their final orbit. And that happened to a group of Starlink satellites last year. Sometimes as well, the satellites or equipment in space, if they fall too fast to the Earth, they can actually reenter. And that big storm we had in May, over a dozen satellites in a period of about an hour reentered the Earth's atmosphere. And the ones that didn't all needed to actually migrate back. So you had 2000 satellites buying their thrusters, the things that controls them and push them back into their lanes. So it's like driving on the highway and everyone changing lanes without a turn signal, which may be not hard to imagine at times, but that was what was happening in space. Yeah, wow. This is a very interesting time to look to the stars, my friend. Thanks, Brad Tucker from ANU. Talk to you soon.