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HiPOD: The Wall of a Crater in Tyrrhena Terra

A public target suggestion from HiWish, this observation was acquired to determine if lava flow was ever present and to evaluate the landscape. This footprint is at the northern edge of a large, unnamed and heavily eroded impact crater. Tyrrhena Terra is heavily cratered and rugged, and is south of Isidis Planitia.

ID: ESP_076984_1795 date: 28 December 2022 altitude: 263 km

NASA/JPL-Caltech/University of Arizona

beautifulmars

HiPOD: A Crater Floor in Sinai Dorsa

Most late-stage lake deposits are low elevation. Is this candidate lake deposit in an impact crater on the Tharsis plateau an exception? In Context Camera data, it looks like confirmed lake deposits. Important if so, because high-elevation lake deposits constrain climate models more stringently than low-elevation lake deposits.

ID: ESP_076898_1660 date: 22 December 2022 altitude: 253 km

NASA/JPL-Caltech/University of Arizona

nasa

Night and (Earth) Day

This image, released in celebration of Earth Day, shows the terminator – the line between night and day – on Earth. The Artemis II astronauts captured this view on April 2, 2026, during their journey to the Moon.

NASA science improves life on Earth every day. We provide insights on our home planet that can only be gathered from space, which can then be used for disaster response, farming, and more. In addition, our observations of Earth and the technologies we develop provide the foundation needed to explore and sustain human life on the Moon, Mars, and beyond.

Download this year's Earth Day poster.

Make sure to follow us on Tumblr for your regular dose of space!

fuckyeahfluiddynamics

Understanding Fish and Turbines

Fish detect turbulence in the water around them; among other things, this helps them avoid colliding with objects. Here, researchers are looking to understand how fish interact with underwater turbines. (Video and image credit: H. Seyedzadeh et al.)

Read the full article

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2026 April 23

Large Scale Structure of the Universe Image Credit: Claire Lamman/DESI collaboration Text: Cecilia Chirenti (NASA GSFC, UMCP, CRESST II)

Explanation: This is a map of the universe. The Dark Energy Spectroscopic Instrument (DESI) at Kitt Peak National Observatory, Arizona, has finished its five-year survey. It observed more than 47 million galaxies and quasars and created a 3D map centered on the Earth. Today’s featured image shows a thin slice of these data: the black gaps indicate where our Galaxy obscures distant objects. The feathery web in the inset shows the large scale structure of the universe. Light of the most distant galaxies shown here travelled for 11 billion years to reach the Earth. Galaxies cluster throughout cosmic history under the competing influences of gravity and dark energy, responsible for the accelerated expansion of the universe. Analysis of early DESI results hinted at the possibility that dark energy, described as a cosmological constant by Albert Einstein, may not be constant after all. But we still have to wait for the analysis of the now complete dataset. The nature of dark energy is the biggest mystery of cosmology.

∞ Source: apod.nasa.gov/apod/ap260423.html

apod

2026 March 9

The Cranium Nebula from the Webb Telescope Image Credit: NASA, ESA, CSA, STScI; Processing: J. DePasquale (STScI)

Explanation: What’s going on inside the head of this nebula? Dubbed the Exposed Cranium Nebula for its similarity to the human brain, what created the nebula remains a mystery. One thought is that the Cranium Nebula, also known as PMR 1, is a planetary nebula surrounding a white dwarf star. In this mode, the outer atmosphere was expelled when the original Sun-like star ran out of central nuclear fuel and contracted. A competing thought is that the central star is much more massive, possibly a Wolf-Rayet star, that is ejecting gas and dust via turbulent stellar winds. Adding to the intrigue is the dark vertical central division and the thin outer gaseous shell. The featured image was taken by the Webb Space Telescope in mid- infrared light, while a second image, included as a rollover, is in near-infrared. Future observations may reveal if this brainy system will quietly just fade from view or, many years from now, suddenly erupt in a powerful supernova.

∞ Source: apod.nasa.gov/apod/ap260309.html

beautifulmars

HiPOD: Slope Streakin’

This image shows many slope streaks of various orientations at fairly high latitude (for slope streaks). Our goal is to monitor for seasonality and directionality of streak formation. We also want to look for fine topographical changes. As the streaks are dark, we can also be on the lookout for winter frost.

ID: ESP_076768_2115 date: 12 December 2022 altitude: 287 km

NASA/JPL-Caltech/University of Arizona

apod

2026 March 10

Sky Glows over Paranal Observatory Image Credit & Copyright: Julien Looten

Explanation: Are lasers from giant telescopes being used to defend the Earth? No. Lasers shot from telescopes are now commonly used to help increase the accuracy of astronomical observations. In some directions, Earth atmosphere-induced fluctuations in starlight can indicate how the air mass over a telescope is changing, but in other directions, no bright star exists. In these directions, astronomers can create an artificial star with a laser. Subsequent observations of the artificial laser guide star can reveal information so detailed about the changing blurring effects of the Earth’s atmosphere that much of it can be removed by rapidly flexing a telescope’s mirror. Such adaptive optics techniques allow high-resolution ground-based observations of real stars, planets, and nebulas. Pictured here, telescopes at Paranal Observatory in Chile study a colorful sky filled with green airglow and the Magellanic Clouds on the left, red airglow on the right, and the majestic central band of our Milky Way Galaxy arching across the center.

∞ Source: apod.nasa.gov/apod/ap260310.html

apod

2026 March 1

The Moon During a Total Lunar Eclipse Video Credit: Wang Letian & Zhang Jiajie

Explanation: How does the Moon’s appearance change during a total lunar eclipse? The featured time-lapse video was digitally processed to keep the Moon bright and centered during the 5-hour eclipse of 2018 January 31. At first the full moon is visible because only a full moon can undergo a lunar eclipse. Stars move by in the background because the Moon orbits the Earth during the eclipse. The circular shadow of the Earth is then seen moving across the Moon. The light blue hue of the shadow’s edge is related to why Earth’s sky is blue, while the deep red hue of the shadow’s center is related to why the Sun appears red when near the horizon. Tomorrow night, people living in Eastern Asia, Australia, and much of North America may get to see a Total Blood Moon Lunar Eclipse. Here the term blood refers to the (likely) red color of a fully eclipsed Moon.

∞ Source: apod.nasa.gov/apod/ap260301.html

fuckyeahfluiddynamics

Icy or Rocky Giants?

On the outskirts of our solar system, two enigmatic giants loom: Uranus and Neptune. In terms of mass and size, both resemble many of the exoplanets discovered in recent years. Within our own solar system, these planets are known as “icy giants,” but a new study suggests that moniker may be wrong. (Image credit: NASA/ESA/A. Simon/M. Wong/A. Hsu; research credit: R. Morf and L. Helled; via Physics World)

apod

2025 December 16

Andromeda and Sprites over Australia Image Credit & Copyright: JJ Rao

Explanation: Whatâ€™s happening over that tree? Two very different things. On the left is the Andromeda galaxy, an object that is older than humanity and will last billions of years into the future. Andromeda (M31) is similar in size and shape to our own Milky Way Galaxy. On the right is a red sprite, a type of lightning that lasts a fraction of a second and occurs above violent thunderstorms. Red sprites were verified as real atmospheric phenomena only about 35 years ago. The tree in the center is a boab, which may live for as long as a thousand years. Boab trees grow naturally in Australia and Africa and are known for being able to store large amounts of water: up to 100,000 liters. The featured image was captured last month near Derby in Western Australia.

∞ Source: apod.nasa.gov/apod/ap251216.html

humanoidhistory

Illustrations by Dean Ellis (1920-2009)

apod

2025 December 1

3I ATLAS: Tails of an Interstellar Comet Image Credit & Copyright: Victor Sabet & Julien De Winter

Explanation: How typical is our Solar System? Studying 3I/ATLAS, a comet just passing through, is providing clues. Confirmed previous interstellar visitors include an asteroid, a comet, a meteor, and a gas wind dominated by hydrogen and helium. Comet 3I/ATLAS appears relatively normal when compared to Solar System comets, therefore providing more evidence that our Solar System is a somewhat typical star system. For example, Comet 3I/ATLAS has a broadly similar chemical composition and ejected dust. The featured image was captured last week from Texas and shows a green coma, a wandering blue-tinted ion tail likely deflected by our Sun’s wind, and a slight anti-tail, all typical cometary attributes. The comet, visible with a telescope, passed its closest to the Sun in late October and will pass its closest to the Earth in mid-December, after which it will return to interstellar space and never return.

∞ Source: apod.nasa.gov/apod/ap251201.html