A recent large survey of low-albedo asteroid spectra in the 3-μm region show a range of hydrated compositions, with one large group similar to the CM chondrites and a second large group showing ...

Visitors in the PSI parking lot view the Moon and Saturn through telescopes on Oct. 28, 2015. Credit: PSI/Alan Fischer On the evening of Oct. 28, 2025, the Planetary Science Institute hosted a ...

Sarah Penniston-Dorland, President of the Mineralogical Society of America, left, presents the 2025 Roebling Medal to Darby Dyar. Credit: Laura Breitenfeld Planetary Science Institute Senior Scientist ...

Your support makes a difference! As a Planetary Partner, YOU will enable our Scientists and Educators to advance world-class Solar System research and grassroots ...

Painting by PSI Cofounder and Senior Scientist Emeritus William K. Hartmann As Siding Spring Comet passed by Mars on Oct. 19, 2014, it broke up in the atmosphere, creating a luminescent shower in the ...

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Let’s do some math. As a target, you need to determine the cross-section of the Moon (target Moon is a disk). The radius of the Moon is 1,737 km, so its cross-sectional area is 9.5 X 10 6 km 2. The ...

SIDEBAR: COMMENT ON OTHER TYPES OF PLOTS This type of plot is called a log-differential plot It is better than the commonly-used cumulative plot of all craters larger than D, because it much more ...

It’s not always easy doing fieldwork at the Ries structure! Many of the quarries are completely overgrown by vegetation. At the top of this slope are some more crater-fill sediments. Lets scramble up ...

DISCOVERY OF ORIENTALE BASIN AND GENERAL MULTI-RING PHENOMENON Hartmann, W. K. and G. P. Kuiper 1962. Concentric Structures Surrounding Lunar basins Comm. Lunar and Planetary Lab., 1, 51-66.

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PSI is a nonprofit 501(c)(3) corporation, and an Equal Opportunity Employer, including disability/veterans.