|
Mbale
chondrite found
on Aug 14, 1992
Esquel
pallasite, NMNH
|
METEORITES
HUNTING
Our Solar system
was created by accretion of dusts and gas there are some 5 billions
years ago. This protosolar cloud contracted such a way it gave birth to
our Sun and its planetary procession.
Meteorites were formed
at that time in the protosolar nebula in a high temperature process that formed
chondrules and melted iron. But the exact nature of this nebula and
processes that developed stay almost unknown.
Therefore
it is very importance that astronomers study these remnant traces of your
oldest past to better understand how the solar system was formed.
According Dr
John A.Wood from Harvard Center of Astrophysics "a meteorite is a seldom object
presenting a true scientific value. The
Center I directed is rented for analyzing private samples too. It may
happen someone brings to us an unknown type of meteorite and for this reason I
hope that all gathered specimens be sent to us, the time to analyze
them".
|
FRENCH PAGES
METEORITES
EXCHANGE
Meteoritical
Society
|
|
Jupiter
rotation, T.16", D.Parker, ALPO
Saturn,
T.10", M.DiSciullo
Mars
near opposition, M.DiSciullo
Pluto
on June 6 -7, 99, C8", K.Tanaka
|
PLANETARY
ACTIVITY
From Venus to
Saturn there are lots of monitoring activities accessible to amateurs
using medium scopes. A typical planetary scope should have a long focal
to get a power great enough to see features in the atmospheres and an aperture over
4"
to say that we see something else than a colored ball suspended in the sky.
The major
activities are :
-
Monitoring the constantly changing in the atmospheric conditions on
Jupiter including the red spot appearance along the years
-
Looking for occasional white spots on Saturn and disturbances in its
rings system
-
Monitoring climate changes on Mars during oppositions (mainly in the
northern cap)
-
Survey the atmosphere of Venus in quest of unusal spots
The
Association of Lunar and Planetary Observers, ALPO, in collaboration
with universities and international institutions organizes for decades
such programs and much more. They can provide you documentation, models
and a survey program that fit to your specifications and interests.
Planets
like Mercury, Uranus, Neptune and Pluto are more
bright "stars" than subjects of monitoring. Their disk is so
small that even using a 16" and colored filters you cannot see more
than a small pinpoint, Uranus excepted. No details, no bands, without great interest
other than the satisfaction to have seen the outer members of the solar
system.
|
Planet
|
Apparent
size
|
Magnitude
|
|
Mercury
|
4.7"
- 12.8"
|
0
|
|
Venus
|
10"
- 1'06"
|
-4
|
|
Mars
|
6"
- 26"
|
1
|
|
Jupiter
|
48"
|
0
|
|
Saturn
|
10"
with rings
|
+1
|
|
Uranus
|
4"
|
5.7
|
|
Neptune
|
2.9"
|
7
|
|
Pluto
|
0.1"
|
16
|
|
During
its oppositions Mercury yield a large disk 12.8" wide, half the one
of the Moon but without details.
But
this is not a reason to not regularly look at them to see an occasional
bright or dark spot. What arrived on Jupiter when comet SL9 collided with
him in 1994 may occur on any other planet tomorrow or later.
|
FRENCH
PAGES
JPL
NSSDC
The
Nine Planets
ALPO
|
|
Alaska,
David Fritss
Alaska,
March 6, 2000
Jan Curtis
Table
Moutain Obs. April 14, 1981 by James Young |
AURORAL
ACTIVITY
Manifestation
of the interactions between the Sun and the Earth geomagnetic field,
auroras are plasma ejections from the solar corona pushed by a disturbed
magnetic field which opens in the space and constituted of high energy
protons and electrons. A large solar mass ejection traveling at higher
velocity can produce a long-duration disturbance and impact the Earth's
magnetosphere 24 hours later with some spectacular visual and physical
effects.
If the ejected
matter is of low velocity they will reach the Earth up to 4 or 5 days
later. If some circumstances the associated magnetic field may be oriented
favorably for increasing levels of geomagnetic and auroral activity
at the Earth to near minor storm levels, with possible brief period
of major storming over the high latitudes regions, in N-NW directions,
disturbing our ionosphere, waves propagation and electrical devices.
Solar
observers paying a close attention to complex active areas of the Sun or
hotter active sunspots region than usual may participate in
near-real-time monitoring and report their observations at the Solar
Terrestrial Dispatch.
His manager
Cary Oler notes also that all people believing they may have spotted
auroral activity are encouraged to report their finding at :
Solar
Terrestrial Dispatch
You
can participate in this program and receive by email AstroAlerts of potential geomagnetic storm
in contacting the US Solar Terrestrial Dispatch.
|
FRENCH PAGES
Ionospheric
Perturbations
Solar
Terrestrial Dispatch
ISTP
SSC-IGPP
SPIDR
- NGDC
IPS
Australia
HAARP |
