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Mbale chondrite found in1992

Esquel pallasite, NMNH


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 to 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".

Note that you can ask for an analysis of a possible specimen that you had found at the Center for Meteorites Studies in th U.S.A., at PASSC in Canada or to any science museum or geology department of a near university.


Center for Meteorites Studies

Meteoritical society

The Meteorites Exchange

Jupiter pictured through a T.16"

by D.Parker, ALPO

Mars at perihelic opposition

pictured by John Earl in 2016

Neptune and Triton pictured in 2015

by Damian Peach with a C14


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, Neptune and Pluto are more bright "stars" than subjects of monitoring. Their disk is so small that using a 20-30 cm (8-12") telescope you cannot see more than a small pinpoint. No details, no spot, thus without great interest other than the satisfaction to have seen the outer members of the solar system. You need a scope from 14" with colored (contrast) filters to start seeing some surface details, mainly by photography after stacking numerous individual frames.


Apparent size















14.5"-20.1" with rings









0.06" 0.11"


During its oppositions Mercury yield a large disk 13" wide, almost half the one of the Moon but without visual details. It is only at high magnifications and stacking several frames that surface details can appear.

After Jupiter, it is Mars and specially during perihelion oppositions that shows the most surface details when its diameter is ranging between 18-25".

But this is not a reason to not regularly look at the other planets to see an occasional bright or dark spot. What happended on Jupiter when comet SL9 collided with hit in 1994 may occur tomorrow on any other planet.




The Nine Planets


Alaska, David Fritss

Aurora over Yukon, Arctic,

on 22 Nov 2015, Yiming Hu


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 to the Solar Terrestrial Dispatch, Spaceweather or to their national observatory.

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 this dispatch.

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Ionospheric Perturbations


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