Hints of Ocean at Ariel
7/25/2024

A team of scientists led by Richard Cartwright from the Johns Hopkins Applied Physics Laboratory has used JWST to determine that Uranus’ moon Ariel has some of the most carbon dioxide-rich deposits in the solar system, as well as evidence of Carbon Monoxide which should not exist at temperatures found at the moon. All this has led to speculation that a sub-surface ocean is helping to replenish the CO through radiolysis.

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Tiny (But Rich!)
7/24/2024

Move over Ft. Knox. NASA scientists recently put forth the idea that tiny Mercury may have up to 10 miles of diamonds as part of its mantle. Using data from the MESSENGER spacecraft which found patches of graphite on the surface, scientists believe that at the interface between mantle and core of the carbon-rich planet a diamond layer would develop.

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2024-10-16 21:08
Start of Carrington Rotation 2290

2024-10-21
Orionid meteor shower

2024-11-16
Leonid meteor shower

2024-11-16
Mercury at greatest eastern (evening) elongation

2024-11-20
Mercury at highest altitude in evening sky

2024-11-21
Uranus at opposition

2024-11-29
Comet 333P/LINEAR reaches perihelion

2024-12-04
Saturn at eastern quadrature

2024-12-07
Jupiter at opposition

2024-12-13
Geminid meteor shower

The Association of Lunar and Planetary Observers (ALPO) is an international organization devoted to study the Sun, Moon, planets, asteroids, meteors, and comets. Our goals are to stimulate, coordinate, and generally promote the study of these bodies using methods and instruments that are available within the communities of both amateur and professional astronomers.

The ALPO collects and analyzes observations of various Solar System bodies and associated phenomena and publishes detailed reports concerning these bodies in its quarterly publication the Journal ALPO, otherwise known as The Strolling Astronomer. Membership in the ALPO includes receiving our journal, and back issues can be found in our Publications section.

We welcome and provide services for all individuals interested in lunar and planetary astronomy. For the novice observer, the ALPO is a place to learn and to enhance observational techniques. For the advanced amateur astronomer, it is a place where one's work will count. For the professional astronomer, it is a resource where group studies or systematic observing patrols add to the advancement of astronomy. Further details about the ALPO can be found here.

There are a range of membership levels available starting with annual dues of only $22. See the footer below for links on how you can become a member today.