Rocket Launches Into Aurora Plus A New Meteorite Falls In China

A two-stage Terrier-Black Brant rocket arced through aurora 200 miles above Earth as the Magnetosphere-Ionosphere Coupling in the Alfvén resonator (MICA) mission investigated the physics of the northern lights. Photo by Terry E. Zaperach, NASA

As some of us stood amazed at the haphazard dance of northern lights last Saturday night, a team of scientists and graduate students from New Hampshire’s Space Science Center watched with equal amazement night as a rocket laden with sensors arced 200 miles into the sky over the Poker Flat Research Range in Fairbanks, Alaska. Its purpose – to learn how Earth’s magnetic bubble (magnetosphere) couples with the upper atmosphere to deliver displays of the northern lights.

Magnetic waves are in part responsible for the multiple arcs of northern lights in Saturday's display. Photo: Bob King

Instruments on board sampled changes in the magnetic and electric fields stimulated by a barrage of electrically charged particles streaming into Earth’s ionosphere from the sun. Scientists hope the information gathered and relayed back to the ground station will help them better understand magnetic waves called Alfvén waves in our upper atmosphere. The waves are thought to be the driving force in the creation of the thick arcs of northern lights often seen spanning the northern sky from east to west during auroral displays. We saw some of these arcs in last Saturday’s aurora.

According to Marc Lessard, an associate professor at the UNH Institute for the Study of Earth, Oceans, and Space (EOS) and department of physics, the Alfvén resonator is a channel in the ionosphere several hundred miles tall and only about six miles wide that acts like a guitar string when “plucked” by energy delivered by the solar wind to Earth’s magnetosphere high above. It’s thought that electrons from the sun’s solar wind (or delivered by flare or coronal mass ejection) are pumped into the channel to create a column of aurora. Complicated physics for sure.

We’ve come a long way since the days when people once thought the aurora was sunlight reflecting off polar ice!

A meteorite fell to the ground in China last week. Click to watch the 3-minute TV report. Credit: CNTV

In other news, a meteor flared over Huangzhong County, Qinghai Province, China on the afternoon of Saturday February 11 leaving several meteorites scattered across the landscape and gouging out at least two small craters. To date four pieces have been recovered. The largest, weighing over 25 lbs., fell on a snowy mountaintop. Clicking on the picture above will take you to an excellent report on the fall by a Chinese TV station.

Take a good look at the fresh meteorite. It’s very typical – pale, cement-like interior with a matte-black fusion crust of melted rock from its high speed burn through the atmosphere. From the appearance alone, the new Chinese meteorite looks like a very primitive but common type of stony chondrite from the outer crust of an asteroid.  For photos of some of the smaller pieces and villagers searching for more, click HERE.

A partial solar eclipse of the sun was photograph in ultraviolet light by the Solar Dynamics Observatory earlier today. Credit: NASA

By the way, did you see the partial eclipse of the sun earlier today? No? Neither did I, since the eclipse wasn’t visible from the ground, but NASA’s Solar Dynamics Observatory did from geosynchronous orbit some 22, 369 miles away. That can only mean that today is new moon. Watch for the moon to scoot away from the sun and return to the evening sky tomorrow.

5 Responses

  1. Roma Rowland

    Hello! I just stumbled across your blog! I can’t believe it took me so long to find it. As a fellow Minnesotan, I say thank you for making your interests and beautiful photographs public. It’s hard to look for the Aurora based on Alaskan predictions when weather is a huge variable here in the state, so it’s nice to watch your blog for predictions. It had been a life goal of mine to see the Aurora and I finally saw it for the first time last Saturday night from North Branch (I’m down in St. Paul). Look forward to reading more- fascinating stuff!
    All the best,

    1. astrobob

      Great to have you along Roma. We’re almost neighbors. Spring and fall are generally the best times for auroras, so I’m sure we’ll have more soon.

    1. astrobob

      Hi Mike,
      I’m using a high-end camera with a CMOS sensor. I try to shoot ISO 800 or 1600 with the lens wide open at f/2.8 to keep the noise down.

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