NASA Astronomy Picture of the Day

Jan 30 2023

Globular Star Cluster NGC 6355 from Hubble

Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are less than 200 left. Over the eons, many globular clusters were destroyed by repeated fateful encounters with each other or the Galactic center. Surviving relics are older than any Earth fossil, older than any other structures in our Galaxy, and limit the universe itself in raw age. There are few, if any, young globular clusters left in our Milky Way Galaxy because conditions are not ripe for more to form. The featured image shows a Hubble Space Telescope view of 13-billion year old NGC 6355, a surviving globular cluster currently passing near the Milky Way's center. Globular cluster stars are concentrated toward the image center and highlighted by bright blue stars. Most other stars in the frame are dimmer, redder, and just coincidently lie near the direction to NGC 6355.

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

>>18253276

NASA spies Martian rocks that look just like a teddy bear

Jan 29 2023

Scientists studying the surface of Mars recently found a piece of the rocky planet smiling back at them.

In an image shared Jan. 25 by The University of Arizona (UA), what appears to be the face of an enormous Martian teddy bear — complete with two beady eyes, a button nose and an upturned mouth — grins at the camera of NASA's Mars Reconnaissance Orbiter (MRO). According to UA, this photo of an uncanny assortment of geological formations was snapped on Dec. 12, 2022, as the MRO cruised roughly 156 miles (251 kilometers) above the Red Planet.

What's really going on here? It's likely just a broken-up hill in the center of an ancient crater, according to a statement posted to UA's High Resolution Imaging Science Experiment (HiRISE) camera blog(opens in new tab).

"There's a hill with a V-shaped collapse structure (the nose), two craters (the eyes), and a circular fracture pattern (the head)," the statement reads. "The circular fracture pattern might be due to the settling of a deposit over a buried impact crater."

https://www.space.com/mars-teddy-bear-face-hirise

https://www.uahirise.org/hipod/ESP_076769_1380