NASA Astronomy Picture of the Day

June 29, 2024

A Solstice Moon

Rising opposite the setting Sun, June's Full Moon occurred within about 28 hours of the solstice. The Moon stays close to the Sun's path along the ecliptic plane and so while the solstice Sun climbed high in daytime skies, June's Full Moon remained low that night as seen from northern latitudes. In fact, the Full Moon hugs the horizon in this June 21 rooftop night sky view from Bursa, Turkey, constructed from exposures made every 10 minutes between moonrise and moonset. In 2024 the Moon also reached a major lunar standstill, an extreme in the monthly north-south range of moonrise and moonset caused by the precession of the Moon's orbit over an 18.6 year cycle. As a result, this June solstice Full Moon was at its southernmost moonrise and moonset along the horizon.

https://apod.nasa.gov/apod/astropix.html?

Hubble Examines an Active Galaxy Near the Lion’s Heart

JUN 28, 2024

It might appear featureless and unexciting at first glance, but NASA/ESA Hubble Space Telescope observations of this elliptical galaxy — known as Messier 105 — show that the stars near the galaxy’s center are moving very rapidly.

Astronomers have concluded that these stars are zooming around a supermassive black hole with an estimated mass of 200 million Suns!

This black hole releases huge amounts of energy as it consumes matter falling into it, making the system an active galactic nucleus that causes the galaxy’s center to shine far brighter than its surroundings.

Hubble also surprised astronomers by revealing a few young stars and clusters in Messier 105, a galaxy thought to be “dead” and incapable of star formation.

Astronomers now think that Messier 105 forms roughly one Sun-like star every 10,000 years.

Astronomers also spotted star-forming activity in a vast ring of hydrogen gas encircling both Messier 105 and its closest neighbor, the lenticular galaxy NGC 3384.

Discovered in 1781, Messier 105 lies about 30 million light-years away in the constellation of Leo (The Lion) and is the brightest elliptical galaxy within the Leo I galaxy group.

https://science.nasa.gov/missions/hubble/hubble-examines-an-active-galaxy-near-the-lions-heart/

Odyssey's THEMIS Views Olympus Mons

June 27, 2024

NASA's 2001 Mars Odyssey orbiter captured this single image of Olympus Mons, the tallest volcano in the solar system, on March 11, 2024. Besides providing an unprecedented view of the volcano, the image helps scientists study different layers of material in the Martian atmosphere, including clouds and dust.

The panorama was created by rotating Odyssey so that its camera, the Thermal Emission Imaging System (THEMIS), faced the horizon of Mars as the orbiter soared past. This shot was among several taken in the latest effort by Odyssey using this technique; capturing this sort of horizon imagery at different times of year allows scientists to study how the atmosphere changes over seasons.

The bluish-white band at the bottom of the atmosphere hints at how much dust was present when the image was captured during Mars' dust season. A purplish layer follows, likely due to a mixture of Mars' red dust with some bluish water-ice clouds. Finally, a blue-green layer can be seen where water-ice clouds reach up about 31 miles (50 kilometers) into the sky.

https://www.jpl.nasa.gov/images/pia26305-odysseys-themis-views-olympus-mons