Ongoing Solar Activity
5 November 2003The Sun has continued its recent high levels of activity. At 1950 UT, 4 November 2003, a class X28 solar flare was released by the Sun. The flare, which is the largest ever recorded, was picked up by the SOHO spacecraft causing instruments to saturate for several minutes.
Fortunately the group of sunspots responsible for this recent activity have now rotated off the face of the Sun and the resulting geomagnetic storm should not be too severe. The solar disk is now completely devoid of sunspots signalling an end to the intense activity of the past two weeks.
SOHO (Solar and Heliospheric Observatory) is located between the Sun and the Earth and will, therefore, detect activity before it reaches the Earth. The spacecraft provides images, across a number of wavebands, x-ray flux measurements, proton counting rates and measurements of the soalr wind. The data can be accessed at the SOHO spaceweather website.
Cluster is an arrangement four spacecraft providing a detailed three-dimensional map of the magnetosphere. Available data includes measurements of the magnetic field, of the ion stream and of proton fluxes in the near Earth environment. The data can be accessed at the Cluster Science Data System website
The Sun shows no sign of calming down just yet. At around 10:30 UT 3 November 2003 another coronal mass ejection was seen by SOHO from the same sunspot group that generated last week's activity. This follows an X8 category eruption at 17:25 UT on 2 November.
All this ongoing solar activity means that the Earth is destined to be bathed in more radiation - generating further auroral displays. Last week's solar activity led to aurora being viewed in many southern states of the USA, such as Texas, Florida and California.
30 October 2003
The intense geomagnetic storm that swept the Earth yesterday has now subsided. At peak intensity the storm registered as a category G5, the highest rating possible.
Although the latest storm maybe subsiding another is on its way. At 2049 UT 29 October 2003 another CME was observed coming from sunspot group 486. This storm is expected to reach Earth sometime tomorrow evening, where auroral activiy is again expected to be high.
29 October 2003
At 06:30 UT 29 October there were indications of increased auroral activity, particularly at mid-latitudes, suggesting that the coronal mass ejection released by the Sun yesterday has reached the Earth.
This ongoing activity has led to several instruments and ESA spacecraft to be put into safe mode to protect them from radiation damage. The latest LASCO images of the Sun show the full impact of the charged particle storm. The images are saturated with interactions making it very difficult to observe ongoing activity.
At 11:10 UT today a coronal mass ejection event was observed on the solar disk. It is associated with the same sunspot group that caused the second flare on the morning of 23 October and is now near the center of the solar disk. The material was ejected at a speed of 2125 kms-1 and will take approximately 20 hours to reach the Earth. The resulting interactions with the Earth and its magnetic field could cause bright auroral displays, even at mid-latitudes, over the next 48 hours.
At 08:35 on 23 October a class X5 solar flare erupted from a sunspot on the solar surface. This giant eruption has sent out a second coronal mass ejection (CME) into space just hours after an earlier eruption. Both CMEs could interact with the Earth and its local space environment sometime in the next 24 to 48 hours.
The first eruption is associated with a large sunspot group now visible near the centre of the solar disk and is visible to naked eye. The second CME came from an active region that is just coming around at the East limb and that SOHO/MDI observed growing on the farside of the Sun last week.
One possible effect of such eruptions could be to disrupt satellite operations or forcing a temporary shut-down of operations to protect against the onslaught. Two spacecraft, however, will remain active - SOHO and Cluster. SOHO and Cluster are both monitoring the Sun and its effects on the near Earth space environment. Data from these spacecraft can be accessed real time enabling you to monitor changes and interactions at the same time as scientists around the world.