Better have a look at this all!!!

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Flares and CMEs

Lots of activity was observed on June 24 with a total of 13 C flares. The most significant event of the day occurred in spotless region 8595. A long duration event started at 12:04 UTC and was visible in LASCO EIT images shortly afterwards. The event peaked at 14:12 UTC at the C4.1 level. A full halo CME (faint over the southeast limb) was observed in LASCO C2 starting at 13:31 UTC. This fairly dense coronal mass ejection is likely to impact earth sometime on June 27 resulting in active to major, perhaps even severe, storm intervals.

I noticed an increase in modem noise, and the phone system at Fred Myers wasn't working, so I thought I would take a peek here http://www.dxlc.com/solar/ have a look

-- Michael (mikeymac@uswest.net), June 25, 1999

Answers

Not trying to infer a conncetion between modem noise or a phone line outage at the super market, just thought you should be aware of possible telecommuniction problems headed our way.

-- Michael (mikeymac@uswest.net), June 25, 1999.

What does UTC stand for? Is that another acronysm for Zulu?

I noticed that my reception on my cell phone was awful yesterday afternoon, between 1500 and 1600 EDT. I was in a location where reception is usually excellent. Related?

-- Arewyn (isitthatlate@lready.com), June 25, 1999.


The SOHO webpage has an interesting artical, click on "SOHO glimpses far side of the Sun, looks at a comet's shadow".

-- Mark Mastrorilli (mastrorilli@hotmail.com), June 25, 1999.

Michael, could you please decode that jargon for us non-astrophysicists and perhaps give some caparative information (e.g., "the last time this amount of solar flare activity occured, every outhouse in Montana spontaneously combusted...")

Thanks much.

-- M.C. Hicks (mhicks@greenwich.com), June 25, 1999.


OHHHHH, M.C. THAT really was funny! The subject isn't...but that outhouse thing sure IS. LOL I needed that laugh. I'm currently flamed up about the NRC, wheeeeew.

-- Will continue (farming@home.com), June 25, 1999.


Arewyn----UTC means Coordinated Universal Time--or Zulu time

-- M. T. Jewell (av8r_99@hotmail.com), June 25, 1999.

Many post concerning "the other Y2K" are available

Here are a couple of sites to help you research

http://cgi.pathfinder.com/time/magazine/archive/1996/dom/960909/space. html

http://www.sel.noaa.gov/info/Cycle23.html

http://www.garynorth.com/y2k/detail_.cfm/162

http://www.sunspotcycle.com/#aurora

These are a few snips that may help to decipher the reports.

UT= Universal time If the ET's are watching there probably laughing their collective antenae off ....{^8`

How do sunspots affect conditions here on Earth? The Earth is affected by both solar flares and sunspots. Solar flares emit high-speed particles which cause auroras, known in the northern hemisphere as Northern Lights. The image shown here is a real-time satellite image of the Earth's auroral region above the North Pole. From the ground auroras appear as shimmering curtains of red and green light in the sky.

Particles from solar flares can also disrupt radio communication, and the radiation from the flares can give passengers in airplanes a dose of radiation equivalent to a medical X-ray. Sunspots may have a long-term connection with the Earth's climate. Scientists are currently debating whether ice ages on Earth are related to the Sun having fewer sunspots than usual.

old not this April --snip-- A strong CME this April caused a moderate geomagnetic storm that affected satellites and communications systems. (April's auroral display online!)

James Spann at NASA's Marshall Space Flight Center, said that it's uncertain whether the CME will be a hit or a miss. The CME was observed by telescopes aboard the Solar Heliospheric Observatory (SOHO) on Nov. 3 and 4.

"There's no way to predict this," he said. "It may miss us or it may hit dead on." Spann is a co-investigator for the Ultraviolet Imager (UVI), one of several instruments aboard the Polar satellite. UVI and its companion, the Visible Imager (VIS) will have the best view of the aurora borealis (northern lights) as they look down on Earth's arctic regions. ...end snip

snip--

"If things do get disturbed, we're going to see a brightening of the aurora with a magnetic substorm or possibly even a storm," he said. A storm in this case has no direct influence on Earth's weather, but it could mean rough sailing for satellites and for electrical power systems on the ground.

Spann and other scientists will be watching data from the Wind spacecraft in a special halo orbit that holds it about a million kilometers away on a line to the sun. Among Wind's instruments is a measure of the solar wind's magnetic field. At this writing it points northward, the same as the Earth's magnetic field. If it flips southward, then things will get exciting a few hours later. Scientists also are watching instruments that measure the speed and density of the solar wind.

If the storm arrives, it will be sometime on Saturday, Nov. 7. The Space Sciences Lab at NASA/Marshall generates automatic MPEG movies every six hours, and our UVI web site posts gif images every 7 minutes while the spacecraft is in a favorable attitude for data downlink.

More may be on the way. The GOES-6 weather satellite earlier today recorded a solar flare emitting strongly in X-rays, often an indication of things to come. As one scientist noted in an e-mail to colleagues, "Hold on to your hats!" end snip--

snip-- Bad weather in space can mean poor radio communications or disrupted power grids here on Earth, and potential hazards to astronauts or spacecraft can be even more serious.

Coronal mass ejections (or CMEs) are huge bubbles of gas threaded with magnetic field lines that are ejected from the Sun over the course of several hours.

Solar flares are tremendous explosions on the surface of the Sun. In a matter of just a few minutes they heat material to many millions of degrees and release as much energy as a billion megatons of TNT. They occur near sunspots, usually along the dividing line (neutral line) between areas of oppositely directed magnetic fields.

Flares release energy in many forms - electro-magnetic (Gamma rays and X-rays), energetic particles (protons and electrons), and mass flows. Flares are characterized by their brightness in X-rays (X-Ray flux). The biggest flares are X-Class flares. M-Class flares have a tenth the energy and C-Class flares have a tenth of the X-ray flux seen in M-Class flares. The National Oceanic and Atmospheric Administration (NOAA)

Coronal Mass Ejections disrupt the flow of the solar wind and produce disturbances that strike the Earth with sometimes catastrophic results. The Large Angle and Spectrometric Coronagraph (LASCO) on the Solar and Heliospheric Observatory (SOHO) has observed a large number of CMEs. The event of April 7th, 1997 is shown to the left (click on the image for the animation). It produced a "halo event" in which the entire Sun appeared to be surrounded by the CME. Halo events are produced by CMEs that are directed toward the Earth. As they loom larger and larger they appear to envelope the Sun itself.

snip-- This region produced some of the most powerful flares ever recorded and remained active over many days. It also illustrates how magnetic shear (twisting of the Sun's magnetic field), is related to solar flares.

The data shown here were taken with the Marshall Space Flight Center's Vector Magnetograph and the co-aligned Hydrogen alpha (H-alpha) telescope. The vector magnetograph looks at light with a wavelength of 525.0 nanometers produced by iron in the solar photosphere. The H-alpha telescope is sensitive to the spectral line at 656.3 nanometers, originating in the Sun's chromosphere, the layer of the solar atmosphere just above the photosphere. Thus, the magnetic fields traced by the chromospheric structures in the H-alpha image overlay the photospheric field measured by the vector magnetograph.

The sequence of images shown above spans more than a nine hour period from 12:07 to 21:20 Universal Time (UT), (7:07am to 4:20pm central daylight savings time). The data include two M-class flares: an M6.4 flare starting at 13:53 UT and ending at 15:27 UT; and an M3.2 flare starting at 16:53 UT and ending at 18:01 UT.

The H-alpha images are displayed in the left-hand panel. The magnetic field measurements are displayed on top of the H-alpha image in the right-hand panel. The solid lines are "neutral lines" that separate areas with opposite magnetic polarity (positive from negative or north from south). The tickmarks point in the direction of the horizontal, or transverse, component of the magnetic field. Normally the transverse field is directed across (or perpendicular to) the neutral lines so that the magnetic field lines travel from the positive polarity regions directly to the negative polarity regions. In this example we see several areas where the tickmarks are directed almost parallel to the neutral lines. The magnetic field is said to be sheared in these regions. Over the last few years we have found that flaring activity is closely associated with sheared magnetic fields.

This region produced some of the most powerful flares ever recorded and remained active over many days. It also illustrates how magnetic shear (twisting of the Sun's magnetic field), is related to solar flares.

The data shown here were taken with the Marshall Space Flight Center's Vector Magnetograph and the co-aligned Hydrogen alpha (H-alpha) telescope. The vector magnetograph looks at light with a wavelength of 525.0 nanometers produced by iron in the solar photosphere. The H-alpha telescope is sensitive to the spectral line at 656.3 nanometers, originating in the Sun's chromosphere, the layer of the solar atmosphere just above the photosphere. Thus, the magnetic fields traced by the chromospheric structures in the H-alpha image overlay the photospheric field measured by the vector magnetograph.

The sequence of images shown above spans more than a nine hour period from 12:07 to 21:20 Universal Time (UT), (7:07am to 4:20pm central daylight savings time). The data include two M-class flares: an M6.4 flare starting at 13:53 UT and ending at 15:27 UT; and an M3.2 flare starting at 16:53 UT and ending at 18:01 UT.

The H-alpha images are displayed in the left-hand panel. The magnetic field measurements are displayed on top of the H-alpha image in the right-hand panel. The solid lines are "neutral lines" that separate areas with opposite magnetic polarity (positive from negative or north from south). The tickmarks point in the direction of the horizontal, or transverse, component of the magnetic field. Normally the transverse field is directed across (or perpendicular to) the neutral lines so that the magnetic field lines travel from the positive polarity regions directly to the negative polarity regions. In this example we see several areas where the tickmarks are directed almost parallel to the neutral lines. The magnetic field is said to be sheared in these regions. Over the last few years we have found that flaring activity is closely associated with sheared magnetic fields.

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Chromospheric Features

The Chromospheric Network

The chromospheric network is a web-like pattern most easily seen in the emissions of the red line of hydrogen (H-alpha) and the ultraviolet line of calcium (Ca II K - from calcium atoms with one electron removed). The network outlines the supergranule cells and is due to the presence of bundles of magnetic field lines that are concentrated there by the fluid motions in the supergranules.

Plage

Plage, the French word for beach, are bright patches surrounding sunspots that are best seen in the red light of hydrogen (H-alpha). Plage are also associated with concentrations of magnetic fields and form a part of the network of bright emissions that characterize the chromosphere.

Filaments

Filaments are dark, thread-like features seen in H-alpha. These are dense, somewhat cooler, clouds of material that are suspended above the solar surface by loops of magnetic field.

Prominences

Prominences are dense clouds of material suspended above the surface of the Sun by loops of magnetic field. Prominences and filaments are actually the same things except that prominences are seen projecting out above the limb, or edge, of the Sun. Both filaments and prominences can remain in a quiet or quiescent state for days or weeks. However, as the magnetic loops that support them slowly change, filaments and prominences can erupt and rise off of the Sun over the course of a few minutes or hours.

Spicules

Spicules are small, jet-like eruptions seen throughout the chromospheric network. They appear as short dark streaks in the H-alpha image to the left (National Solar Observatory/Sacramento Peak). They last but a few minutes but in the process eject material off of the surface and outward into the hot corona at speeds of 20 to 30 km/s. I became very interested in this recent report here... http://www.dxlc.com/solar... because I have not seen the double red condition on the probability chart before. I have not been able to ascertain the signifigance of X flares yet.

I also could not find the information I had on the meltdown of eletronic equipment during a past event in which the powergrid was damaged in Canada, if memory serves.

Anyway, I just thought anyone else who is watching may like to check out the upcoming storm info..



-- Michael (mikeymac@uswest.net), June 25, 1999.


please keep info coming. I have heard from a friend that the military is more concerned with flares than y2k at this point. Can you keep us posted on the June 27 event?

-- Moore Dinty moore (not@thistime.com), June 25, 1999.

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