July 24, 2025, TUCSON, Ariz. – On the slopes of Martian mountains and craters clings what appears to be flowing honey, coated in dust and frozen in time. In reality, these features are incredibly slow ...

July 15, 2025, TUCSON, Ariz. – The United Nations General Assembly agreed in 2021 to dub July 20 International Moon Day, which celebrates the anniversary of the first landing by humans on the Moon on ...

A decade ago this week, NASA’s New Horizons mission snapped the first-ever close-up image of Pluto. The awe-inspiring portrait of the dwarf planet featured a heart-shaped plane of frozen nitrogen and ...

Field Guide to the Santa Fe impact structure (from 2017 Annual Meeting of the Meteoritical Society in Santa Fe, NM) Depositional contacts of loess and basalt as an analog for dust on Mars… ...

A new analysis of maps of the near and far sides of the Moon shows that there are multiple sources of water and hydroxyl in the sunlit rocks and soils, including water-rich rocks excavated by meteor… ...

Oct. 28, 2024, TUCSON, Ariz. – The Moon and Mars are pocked with giant impact craters acquired very long ago, while there appears to be a dearth of them on Earth and Venus. Time may have healed many ...

A mysterious object discovered in the main asteroid belt in 2021 was determined to be a main-belt comet by Planetary Science Institute Senior Scientist Henry Hsieh, Scott Sheppard of the Carnegie ...

Stars that pass by our Solar System have altered the long-term orbital evolution of planets, including Earth, and by extension modified our climate.

Nov. 1, 2024, TUCSON, Ariz. – On a cold, ancient Mars, rivers flowed and a lake the size of the Mediterranean Sea swelled under the protection of thick ice ceilings, according to new research ...

PSI senior education and communication specialists Sanlyn Buxner and Larry Lebofsky facilitated a three-day institute for educators of young children and elementary school students. The 2024 STEMAZing ...

Dec. 18, 2024, TUCSON, Ariz. – The Planetary Science Institute has selected University of Arizona graduate student Namya Baijal and Indian Institute of Technology Kanpur doctoral candidate Mishal K T ...

The march of the planets around the Sun may seem interminable, but new research suggests that the likelihood of another star in our galaxy passing by and disrupting our Solar System is slightly higher ...