Friday, October 23, 2020

Globular Star Cluster 47 Tuc

Globular star cluster 47 Tucanae is a jewel of the southern sky. Also known as NGC 104, it roams the halo of our Milky Way Galaxy along with some 200 other globular star clusters. The second brightest globular cluster (after Omega Centauri) as seen from planet Earth, it lies about 13,000 light-years away and can be spotted naked-eye close on the sky to the Small Magellanic Cloud in the constellation of the Toucan. The dense cluster is made up of hundreds of thousands of stars in a volume only about 120 light-years across. Red giant stars on the outskirts of the cluster are easy to pick out as yellowish stars in this sharp telescopic portrait. Tightly packed globular cluster 47 Tuc is also home to a star with the closest known orbit around a black hole. via NASA

Thursday, October 22, 2020

Supernova in NGC 2525

Big, beautiful, barred spiral galaxy NGC 2525 lies 70 million light-years from the Milky Way. It shines in Earth's night sky within the boundaries of the southern constellation Puppis. About 60,000 light-years across, its spiral arms lined with dark dust clouds, massive blue stars, and pinkish starforming regions wind through this gorgeous Hubble Space Telescope snapshot. Spotted on the outskirts of NGC 2525 in January 2018, supernova SN 2018gv is the brightest star in the frame at the lower left. In time-lapse, a year long series of Hubble observations followed the stellar explosion, the nuclear detonation of a white dwarf star triggered by accreting material from a companion star, as it slowly faded from view. Identified as a Type Ia supernova, its brightness is considered a cosmic standard candle. Type Ia supernovae are used to measure distances to galaxies and determine the expansion rate of the Universe. via NASA

Wednesday, October 21, 2020

Tagging Bennu

On October 20, after a careful approach to the boulder-strewn surface, the OSIRIS-REx spacecraft's arm reached out and touched asteroid Bennu. Dubbed a Touch-And-Go (TAG) sampling event, the 30 centimeter wide sampling head (TAGSAM) appears to crush some of the rocks in this snapshot. The close-up scene was recorded by the spacecraft's SamCam some 321 million kilometers from planet Earth, just after surface contact. One second later, the spacecraft fired nitrogen gas from a bottle intended to blow a substantial amount of Bennu's regolith into the sampling head, collecting the loose surface material. Data show the spacecraft spent approximately 5 more seconds in contact with Bennu's Nightingale sample site and then performed its back-away burn. Timelapse frames from SamCam reveal the aftermath. via NASA

NASA to Announce New Science Results About Moon

NASA will announce an exciting new discovery about the Moon from the Stratospheric Observatory for Infrared Astronomy (SOFIA) at a media teleconference at 12 p.m. EDT Monday, Oct. 26. via

Tuesday, October 20, 2020

A Night Sky Vista from Sardinia

How many famous sky objects can you find in this image? The featured dark sky composite combines over 60 exposures spanning over 220 degrees to create a veritable menagerie of night sky wonders. Visible celestial icons include the Belt of Orion, the Orion Nebula, the Andromeda Galaxy, the California Nebula, and bright stars Sirius and Betelgeuse. You can verify that you found these, if you did, by checking an annotated version of the image. A bit harder, though, is finding Polaris and the Big Dipper. Also discernible are several meteors from the Quandrantids meteor shower, red and green airglow, and two friends of the astrophotographer. The picture was captured in January from Sardinia, Italy. You can see sky wonders in your own night sky tonight -- including more meteors than usual -- because tonight is near peak of the yearly Orionids meteor shower. via NASA

NASA’s OSIRIS-REx Spacecraft Successfully Touches Asteroid

NASA’s Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) spacecraft unfurled its robotic arm Tuesday, and in a first for the agency, briefly touched an asteroid to collect dust and pebbles from the surface for delivery to Earth in 2023. via

Monday, October 19, 2020

Saturn and Jupiter over Italian Peaks

Saturn and Jupiter are getting closer. Every night that you go out and check for the next two months, these two bright planets will be even closer together on the sky. Finally, in mid-December, a Great Conjunction will occur -- when the two planets will appear only 0.1 degrees apart -- just one fifth the angular diameter of the full Moon. And this isn't just any Great Conjunction -- Saturn (left) and Jupiter (right) haven't been this close since 1623, and won't be nearly this close again until 2080. This celestial event is quite easy to see -- already the two planets are easily visible toward the southwest just after sunset -- and already they are remarkably close. Pictured, the astrophotographer and partner eyed the planetary duo above the Tre Cime di Lavaredo (Three Peaks of Lavaredo) in the Italian Alps about two weeks ago. via NASA