Subj: SOLAR ERUPTION MAY FLOOD EARTH - AND - SIBERIAN SPACE LIGHT SHOW
Date: 6/9/00 6:48:33 AM Pacific Daylight Time

Tuesday, 2 May, 2000, 14:48 GMT 15:48 UK
Solar eruption may flood Earth
http://news.bbc.co.uk/hi/english/sci/tech/newsid_733000/733591.stm

Image: Solar and Heliospheric Observatory (Soho)

An outburst of superhot gas from the Sun may be travelling towards
Earth, with an expected arrival time of about 2300 BST (2200 GMT) on
Tuesday.
The eruption, called a Coronal Mass Ejection, was spotted on Sunday by a
spacecraft, the Solar and Heliospheric Observatory (Soho).

[SEE: http://sec.noaa.gov/getftp.cgi?get=plots/xray/20000605_xray.gif]

The burst of gas will enhance the solar wind, currently running at 685
kilometres per second, and produce a shock wave which could wash over
the Earth.




Increased solar winds mean bright aurorae

If this occurs, then spectacular aurorae will be seen at higher
latitudes.

The direction of CME is uncertain because the specific shape observed
could be caused not just by an Earth-directed outburst, but also by the
superposition of two or more smaller events, directed away from Earth.

The US National Oceanographic and Atmospheric Administration has
forecast a 40% chance of some geomagnetic storm activity over Tuesday
and Wednesday, with the chance at mid-latitudes being 30%.

Severe geomagnetic storm activity can affect power supplies on Earth and
satellites in orbit.

The Sun's activity waxes and wanes over an 11-year cycle and this year
the activity reaches its maximum.

+++++++++++++++++++

Friday, 9 June, 2000, 12:15 GMT 13:15 UK

Siberian space light show

http://news.bbc.co.uk/hi/english/sci/tech/newsid_783000/783984.stm

The Northern Lights formed a ring around the magnetic pole

By BBC News Online science editor Dr David Whitehouse
Dramatic shows of the northern lights have illuminated Siberia, but the
chances for further widespread auroras over the northern hemisphere are
declining.

The Earth's magnetosphere is now settling down after being disrupted by
an interplanetary shock wave.




The Advanced Compositional Explorer

The shock wave began in an explosion on the surface of the Sun on 6
June. As well as an energetic solar flare, a mass of super-hot ionised
gas was propelled towards the Earth.

The first indications that the so-called coronal mass ejection (CME)
were heading for the Earth was from the Soho Sun-monitoring satellite
and the Advanced Composition Explorer (Ace) that are positioned closer
to the Sun than the Earth.

Both recorded a jump in the speed of the solar wind from about 500 km
per second (310 miles per second) to over 700 km per second (434 miles
per second). The number of sub-atomic particles in the solar wind
doubled.

The disturbance arrived at Earth about an hour later, triggering some
intense auroras that were best seen from Northern Asia.

Satellite spy

The charged particles from the CME were drawn towards the Earth by the
planet's magnetic field and struck the upper atmosphere near the
magnetic poles. Earth-orbiting satellites looking down on the polar
regions detected a characteristic ring of auroral light.

The solar wind has now declined to pre-shock levels. Scientists say that
the interplanetary magnetic field has also adopted a posture that is
generally unfavourable for displays of aurora today.

Further flares are bound to occur on the solar surface as the Sun
reaches its peak of activity this summer.