Go Sun!! Biggest Solar Flare since 2005!

Evolution of the January 23, 2012 solar flare. Images, from left to right,
taken at 3:27, 3:42, and 4:13 UT. NASA Solar Dynamics Observatory

After a solar minimum that was unusually quiet and prolonged, the Sun has reawakened. Following the January 21 flare (previous post), the biggest outburst since 2005 occurred late on Sunday night, January 22, 2012, around 11:00 p.m. EST, sending a shower of charged protons toward the earth. (The flare was assigned a M8.7 intensity, and is expected to hit the earth today at 9 AM ET (plus or minus 7 hours). Here's the NASA release.

What is the difference between a solar flare and a coronal mass ejection? A solar flare is an intense burst of radiation from a sunspot as magnetic energy is released in an explosive event. It releases light at almost every wavelength of the spectrum.  A coronal mass ejection is mass released during a flare, primarily gas, often billions of tons.  CME's are sometimes associated with flares, but can also occur independently of a flare.

How are solar flares classified?
Solar flares are classified on a logarithmic scale (similar to the Richter magnitude scale), with each class having a peak flux ten times greater than the preceding one.  The flux is measured in watts per square meter (W/m**2) in a particular wavelength range (100-800 picometer X-rays) near the Earth, as measured by GEOS spacecraft. Within each class there are 9 sub-categories, each being twice as big as the previous one.  The classes are, in increasing order, A,B,C,M, and X. The flare discussed here was rated as a M8.7, just slightly below the most intense X category.

How is the effect of a flare on the earth classified?
A solar flare and CME can cause a geomagnetic storm on the earth, a disruption of our magnetosphere.
Here's a link to the classification of the effects of geomagnetic storms on earth.

Here's a link to a longer explanation.

Here, here, and here are previous posts on this blog that might be of interest.

Solar "Blob" of Plasma Headed our Way

The Sun on January 21, 2012
Sunspot 1401 erupted on January 19

According to Spaceweather.com, sunspot #1401 erupted on Friday around 16:30 UT producing a solar flare and coronal mass ejection (CME). The cloud is heading toward the earth. A

Here is a neat animation of the forecast, showing not only the Earth, but Mars, Mercury and Venus as well as a few spacecraft in orbit. The cloud is expected to hit here on Saturday, around 22:30 UT (plus or minus 7 hours). (The Space Weather Prediction Center has forecast that it will hit at high northern latitudes around 1:00 p.m. EST on Sunday, with the bulk of the disturbance on Monday.) Initially there were apparently fears that this would be a direct blast that could seriously threaten communications and satellites, but the Post reports that it is more likely going to be a glancing blow affecting high latitudes. It will reach Mars on January 24th.

We are heading toward a sunspot maximum in 2013, and sunspot activity and flares like this may increase. Another consequence of increasing sunspot activity is that the UV radiation levels increase from the sunspots. This activity "puffs up" the earth's atmosphere which puts drag on low-altitude space debris, causing it to slow down and eventually fall out of orbit.  Space debris has become a major concern for safety of the astronauts in orbit, and getting rid of some of it in this way is a good thing. I hadn't been aware, but in 2007 the Chinese "killed" one of their weather satellites in a test, creating over 3,000 pieces of debris bigger than golf-ball size. Only 6% of this debris has re-entered the earth's atmosphere.  There was also a collision of Cosmos 2251 and Iridium 33 satellites that created debris.

Could be some good aurora somewhere!

Here's more on CME's and sunspots from earlier posts: (1) The 1859 Solar Superstorm; (2) Solar Activity (and Newt Gingrich)--well, that's relevant today since it's the South Carolina Republican primary vote!!)

Great visualization of the Costa Concordia situation

Here's a nice graphic of the situation with the Costa Concordia:

http://news.sky.com/home/interactive-graphics/costa-concordia

Of sailing ships: Froude numbers

HMS Dreadnought
U.S. Naval History & Heritage Command photo

As an island nation, England has had a long tradition of strong navy ships, but ship casualties at sea were high, not just because of battle and pirates, but because of poor design. The Victorian Age was also the age of the ironclads--massive heavy ships.  One such ship was the "Captain", which turned turtle in 1871 with the loss of almost 500 lives.

A father-son team, William and Robert Froude had been working on ship design and had been conducting experiments with small ships on the River Dart, and later had built their own testing tank at Chelston Cross.**  When the Captain turned turtle, Froude gained support (an enormous sum of 2000 pounds!!) to cover the cost of building a tank in which he could test scale models of ships. This was to revolutionize ship-building, a practice that until then had been done by simple reliance on the experience of shipwrights.

William Froude died in 1879 at the age of 69, and a few years later the original experimental tank (called the Torquay tank) became obsolete.  Robert Froude built a new tank, 475 feet long, 20 feet wide, and 9 feet deep at Haslar. By 1918, over 500 warship models had been tested there, including the "Dreadnought," a revolutionary battleship that rammed and sank the U-29 German submarine during World War I.

Froude was concerned with reducing the drag on ships, and with the problem of applying results obtained from his models to the enormous battleships. There are two sources of drag on ships: viscous resistance from water on the hull, and wave-making resistance, the energy dissipated forming the waves that follow ships (the characteristic V-shaped wake behind ships). At high-speed the wave-making resistance accounts for 50-60% of the resistance.  The drag increased with the speed of the ship, and decreased for larger and larger ships.  A dimensionless parameter, now known as the Froude number, expressed this relation:

Fr = v/((gL)**0.5)

At low Froude numbers (low velocity and/or big long ship) viscous resistance dominates. At Fr=0.4 to 0.5, wave resistance dominates. Most conventional ships operate at Fr<0.4.


**Here's the reference on the two Froudes.
Here's a source of some of the other information that I used here.

Marine Salvage: Costa Concordia and The Cougar Ace

Costa Concordia
By Andreas Solaro/AFP/Getty Images

As searches continue for more victims in the submerged parts of the Costa Concordia, salvage operations are also beginning.  It appears that Dutch Smit and Salvage is doing the salvage. (Dutch salvagers have long dominated the trade because of the expertise with pumps developed to keep The Netherlands dry.) They have equipment in place already to keep track of the ship's movement, and equipment to begin transferring fuel out of the ship could be ready to proceed on Wednesday (the 18th).  The Concordia is nearly twice the size of the Titanic, and salvage operations will be fascinating to follow. The Cougar Ace was 654 feet long, and had 23 people on board.

Marine salvage law is complex, and perhaps a reader would like to comment. I decided, instead, to look at some previous salvage efforts. I found a great article in Wired Magazine in 2008 called "High tech cowboys of the deep seas: the race to save The Couger Ace."

The Cougar Ace
Photo by U.S. Coast Guard

The Couger Ace was a deep-sea car transport ship with 14 decks packed with 4,703 brand new Mazdas bound for North America, a cargo estimated to be worth $103 million (for comparison, the Costa Concordia alone is a $500 million dollar ship that was carrying over 4,000 passengers and crew.) The Couger Ace was about 230 miles south of the Aleutian Islands in a heavy fog. The captain and crew started the ballast water taken on in Japan to replace it with local water, a procedure that the US requires to prevent contaminating American marine environments with foreign life. It's a tricky procedure to maintain stability and equilibrium.

Something went wrong during the procedure and the starboard ballast tanks failed to refill properly. The ship rolled, and just at the wrong time, a large swell hit and exaggerated the roll. The salvage operation was run by Titan Salvage, led by Rich Habib. The crew of such an operation has a wide range of skills--deep-sea diving, computer modeling, underwater welding, engine repair. A key person on this team is the naval architect capable of building digital 3-D ship models to plan and execute salvage procedures, an approach quite different from the Dutch pumping approaches.

Meanwhile, The Cougar Ace was drifting toward rocks on the shores of the Aleutian Islands and was taking on water. The danger was losing the ship, the cars, and 176,000 gallons of fuel in an area of rich wildlife and fishing grounds. The insurers felt that the ship was lost, but then executed a "Lloyd's Open Form agreement" with Titan: if they don't save the ship, they don't get paid. If they save the ship, the compensation is based on the value of the ship and cargo, and is a fortune.

The naval architect, Marty Johnson, took a fall and died during the salvage. The crew eventually built a digital model of the ship and developed a plan for shifting water between ballast tanks. You have to read the full (and long) report to get a feel for the difficulties of the operation. Bottom line is that although they righted the ship and saved all the cars, they had sat at a 60-degree angle for two weeks and Mazda couldn't be sure that there wouldn't be problems. Would the air bags function properly after such an event? Will the engines live out their warranty?  After a year, 4,703 Mazdas were loaded one-by-one onto a converyor belt that removed them from the ship and dropped them into a "Texas Shredder," a 50' tall machine that smashed each car to small chunks.