Well, it’s high summer here north of the equator, and for those of you without incessant rains coming down from the sky, the stars must be lookin’ pretty good right about now. I always like to go out and look for Sagittarius, which from my latitude is pretty far south and the tail just grazes the horizon. There’s a lot of stuff out that way — the center of the Milky Way lies in that direction, and so do a number of nice star clusters and some nebulae. It’s one of my favorite places to look with binoculars. The Milky Way also skims right over head later in the evening, and if I can find a spot in the grass without chiggers or mites or skeeters (mossies, for those of you in Australia), it’s really rewarding to lay back and just gaze at that (with or without binoculars).
I remember as a kid doing that “laying in the grass and looking up at the skies thing” and trying to count stars. An impossible task. There are a few thousand, not counting the ones you’d need magnification to see (either too dim or too far away or too crowded together in clusters and the Milky Way). But, don’t let that stop you from trying.
Here’s a challenge for you: get out there every night and look up. Just do it. No excuses. Get a star chart (if you don’t have one, get one here: Skymaps. Print it out, study it. Then go out there and use it to identify a constellation or two. Maybe some bright stars. If you’re daring, you might see if you can find some clusters. They’re out there. And if the weather is good for you (warm, dry, comfy), try it every night. Go on do it. I dare ya. Me? I’ll do it, too. But first I have to find some clear skies. It’s been raining here for a week. And, for the next seven days, I’ll be absorbed in moving to a new house. But, I’ll check in with you, to make sure you’re stargazing. Watching the stars is free — and, as they say — in this economy — free is good.
First view of what goes on below the surface of sunspots. Lighter/brighter colors indicate stronger magnetic field strength in this subsurface cross section of two sunspots. For the first time, NCAR scientists and colleagues have modeled this complex structure in a comprehensive 3D computer simulation, giving scientists their first glimpse below the visible surface to understand the underlying physical processes. (Click to embiggen.)
Today’s what lots of folk think of as the first day of summer for us northern hemisphere types and first day of winter for the southern hemisphere folks. (It’s actually the mid-point, marking the point when the Sun is the farthest north in its yearly path across the sky.) Today’s the solstice and FATHER’s DAY here in the U.S…. and just in time for this auspicious occasion, the folks at National Center for Atmospheric Research (NCAR) and the Max Planck Institute for Solar System Research bring us a wonderful computer model of sunspots. I’m dedicating today’s entry to my dad, who loves to look at sunspots! This one’s for you, Daddy!
The high-res simulations of sunspots are an important tool for scientists to learn more about these blots of seemingly dark regions on the Sun (I say “seemingly” because they’re actually just cooler than the surrounding area, thus appearing darker). Sunspots are manifestations of the magnetic fields that play across the Sun’s surface. They’re also closely associated with massive ejections of material that can come straight at Earth and cause things like aurorae, or even go so far as to disrupt our communications networks and power systems. You may have heard of the term “space weather” — well, sunspots are often involved in the processes that cause space weather. If you’ve been following the Space Weather FX project I’ve been working on for Haystack Observatory, we’ve been talking a lot about the effects of space weather on all kinds of systems.
Creating detailed simulations of sunspots would not have been possible even as recently as a few years ago. But now, we have the latest generation of supercomputers and a growing array of instruments to observe the Sun — and when you marry the two, you can get some amazing simulations of real life. Partly because of such new technology, scientists have made advances in solving the equations that describe the physics of solar processes. The Sun is a complex object, ever-changing and difficult to probe. So, coming up with a computer model is an important step. “This is the first time we have a model of an entire sunspot,” says lead author Matthias Rempel, a scientist at NCAR’s High Altitude Observatory. “If you want to understand all the drivers of Earth’s atmospheric system, you have to understand how sunspots emerge and evolve. Our simulations will advance research into the inner workings of the Sun as well as connections between solar output and Earth’s atmosphere.”
Outward flows from the center of sunspots were discovered a hundred years ago, and ever since then, atmospheric physicists have been working on explanations for the very complex structures they see in sunspots. This includes the fact that their numbers rise and fall during each 11-year solar cycle.
The work was supported by the National Science Foundation, NCAR’s sponsor. The research team improved a computer model, developed at MPS, that built upon numerical codes for magnetized fluids that had been created at the University of Chicago. GO read more about it (and see some of their really COOL videos) at the UCAR/NCAR web site.
