Apod - Blog Posts

Happy Halloween, everyone!

2024 October 27

LDN 43: The Cosmic Bat Nebula Credit & Copyright: Mark Hanson and Mike Selby; Text: Michelle Thaller (NASA’s GSFC)

Explanation: What is the most spook-tacular nebula in the galaxy? One contender is LDN 43, which bears an astonishing resemblance to a vast cosmic bat flying amongst the stars on a dark Halloween night. Located about 1400 light years away in the constellation Ophiuchus, this molecular cloud is dense enough to block light not only from background stars, but from wisps of gas lit up by the nearby reflection nebula LBN 7. Far from being a harbinger of death, this 12-light year-long filament of gas and dust is actually a stellar nursery. Glowing with eerie light, the bat is lit up from inside by dense gaseous knots that have just formed young stars.

∞ Source: apod.nasa.gov/apod/ap241027.html

2024 February 4

The Cone Nebula from Hubble Image Credit: Hubble Legacy Archive, NASA, ESA - Processing & Licence: Judy Schmidt

Explanation: Stars are forming in the gigantic dust pillar called the Cone Nebula. Cones, pillars, and majestic flowing shapes abound in stellar nurseries where natal clouds of gas and dust are buffeted by energetic winds from newborn stars. The Cone Nebula, a well-known example, lies within the bright galactic star-forming region NGC 2264. The Cone was captured in unprecedented detail in this close-up composite of several observations from the Earth-orbiting Hubble Space Telescope. While the Cone Nebula, about 2,500 light-years away in Monoceros, is around 7 light-years long, the region pictured here surrounding the cone’s blunted head is a mere 2.5 light-years across. In our neck of the galaxy that distance is just over half way from our Sun to its nearest stellar neighbors in the Alpha Centauri star system. The massive star NGC 2264 IRS, seen by Hubble’s infrared camera in 1997, is the likely source of the wind sculpting the Cone Nebula and lies off the top of the image. The Cone Nebula’s reddish veil is produced by dust and glowing hydrogen gas.

∞ Source: apod.nasa.gov/apod/ap240204.html

Beautiful!

2023 September 26

IC 4592: The Blue Horsehead Reflection Nebula Image Credit & Copyright: Antoine & Dalia Grelin

Explanation: Do you see the horse’s head? What you are seeing is not the famous Horsehead nebula toward Orion, but rather a fainter nebula that only takes on a familiar form with deeper imaging. The main part of the here-imaged molecular cloud complex is reflection nebula IC 4592. Reflection nebulas are made up of very fine dust that normally appears dark but can look quite blue when reflecting the visible light of energetic nearby stars. In this case, the source of much of the reflected light is a star at the eye of the horse. That star is part of Nu Scorpii, one of the brighter star systems toward the constellation of the Scorpion (Scorpius). A second reflection nebula dubbed IC 4601 is visible surrounding two stars above and to the right of the image center.

∞ Source: apod.nasa.gov/apod/ap230926.html

Wow, it really does look like a hummingbird!

2023 September 25

Arp 142: The Hummingbird Galaxy Image Credit: NASA, ESA, Hubble, HLA; Processing & Copyright: Basudeb Chakrabarti

Explanation: What’s happening to this spiral galaxy? Just a few hundred million years ago, NGC 2936, the upper of the two large galaxies shown at the bottom, was likely a normal spiral galaxy – spinning, creating stars – and minding its own business. But then it got too close to the massive elliptical galaxy NGC 2937, just below, and took a turn. Sometimes dubbed the Hummingbird Galaxy for its iconic shape, NGC 2936 is not only being deflected but also being distorted by the close gravitational interaction. Behind filaments of dark interstellar dust, bright blue stars form the nose of the hummingbird, while the center of the spiral appears as an eye. Alternatively, the galaxy pair, together known as Arp 142, look to some like Porpoise or a penguin protecting an egg. The featured re-processed image showing Arp 142 in great detail was taken recently by the Hubble Space Telescope. Arp 142 lies about 300 million light years away toward the constellation of the Water Snake (Hydra). In a billion years or so the two galaxies will likely merge into one larger galaxy.

∞ Source: apod.nasa.gov/apod/ap230925.html

2023 December 29

Shakespeare in Space Image Credit: NASA, ESA, CSA, STScI

Explanation: In 1986, Voyager 2 became the only spacecraft to explore ice giant planet Uranus close up. Still, this newly released image from the NIRCam (Near-Infrared Camera) on the James Webb Space Telescope offers a detailed look at the distant world. The tilted outer planet rotates on its axis once in about 17 hours. Its north pole is presently pointed near our line of sight, offering direct views of its northern hemisphere and a faint but extensive system of rings. Of the giant planet’s 27 known moons, 14 are annotated in the image. The brighter ones show hints of Webb’s characteristic diffraction spikes. And though these worlds of the outer Solar System were unknown in Shakespearean times, all but two of the 27 Uranian moons are named for characters in the English Bard’s plays.

∞ Source: apod.nasa.gov/apod/ap231229.html

The Seyfert galaxy NGC 5985 (on the left) contains an Active Galactic Nucleus (AGN).

AGN are so. Amazing.

In the dead center of the galaxy lies a supermassive black hole—and a large amount of other matter spiraling into it, caught in the gravitational well. As matter falls in, it accelerates to relativistic speeds, ripping apart until even atoms are split into plasma, and because plasma is not electrically neutral the metaphorical whirlwind of it generates an extremely strong electromagnetic field.

That field blasts matter away from the black hole in jets. These can be truly enormous. A single jet emanating from the black hole in the monstrous elliptical galaxy M87 is roughly ten times the length of our entire Milky Way Galaxy.

Seyfert galaxies are calmer than that, but the mechanism is the same. Bright, powerful AGN tend to be found in galaxies further from our own, while Seyferts dominate the AGN population in our local universe.

At BSU, we've imaged Markarian 421, a type of AGN called a blazar, so-named because the jet is aimed almost directly toward Earth.: "blazing" bright. We're in the process of studying our data, but the eventual goal is to determine limits for the mass of the black hole powering it. The student who spearheaded that research is now pursuing a Ph.D. at Purdue University!

2023 July 1

Three Galaxies in Draco Image Credit & Copyright: David Vernet , Jean-François Bax , Serge Brunier, OCA/C2PU

Explanation: This tantalizing trio of galaxies sometimes called the Draco Group, is located in the northern constellation of (you guessed it) Draco, the Dragon. From left to right are face-on spiral NGC 5985, elliptical galaxy NGC 5982, and edge-on spiral NGC 5981, all found within this single telescopic field of view that spans a little more than the width of the full moon. While the group is far too small to be a galaxy cluster, and has not been catalogued as a compact galaxy group, the three galaxies all do lie roughly 100 million light-years from planet Earth. Not as well known as other tight groupings of galaxies, the contrast in visual appearance still makes this triplet an attractive subject for astroimagers. On close examination with spectrographs, the bright core of striking spiral NGC 5985 shows prominent emission in specific wavelengths of light, prompting astronomers to classify it as a Seyfert, a type of active galaxy. This impressively deep exposure hints at a faint dim halo along with sharp-edged shells surrounding elliptical NGC 5982, evidence of past galactic mergers. It also reveals many even more distant background galaxies.

∞ Source: apod.nasa.gov/apod/ap230701.html

2024 January 9

Thor’s Helmet Image Credit & Copyright: Ritesh Biswas

Explanation: Thor not only has his own day (Thursday), but a helmet in the heavens. Popularly called Thor’s Helmet, NGC 2359 is a hat-shaped cosmic cloud with wing-like appendages. Heroically sized even for a Norse god, Thor’s Helmet is about 30 light-years across. In fact, the cosmic head-covering is more like an interstellar bubble, blown with a fast wind from the bright, massive star near the bubble’s center. Known as a Wolf-Rayet star, the central star is an extremely hot giant thought to be in a brief, pre-supernova stage of evolution. NGC 2359 is located about 15,000 light-years away toward the constellation of the Great Overdog. This remarkably sharp image is a mixed cocktail of data from narrowband filters, capturing not only natural looking stars but details of the nebula’s filamentary structures. The star in the center of Thor’s Helmet is expected to explode in a spectacular supernova sometime within the next few thousand years.

∞ Source: apod.nasa.gov/apod/ap240109.html

2024 January 16

The Orion You Can Almost See Image Credit & Copyright: Michele Guzzini

Explanation: Do you recognize this constellation? Although it is one of the most recognizable star groupings on the sky, this is a more full Orion than you can see – an Orion only revealed with long exposure digital camera imaging and post- processing. Here the cool red giant Betelgeuse takes on a strong orange tint as the brightest star on the upper left. Orion’s hot blue stars are numerous, with supergiant Rigel balancing Betelgeuse on the lower right, and Bellatrix at the upper right. Lined up in Orion’s belt are three stars all about 1,500 light-years away, born from the constellation’s well-studied interstellar clouds. Just below Orion’s belt is a bright but fuzzy patch that might also look familiar – the stellar nursery known as Orion’s Nebula. Finally, just barely visible to the unaided eye but quite striking here is Barnard’s Loop – a huge gaseous emission nebula surrounding Orion’s Belt and Nebula discovered over 100 years ago by the pioneering Orion photographer E. E. Barnard.

∞ Source: apod.nasa.gov/apod/ap240116.html

In case of confusion, the observatory is not open this Wednesday.

As consolation, here's the 'Great Turkey Nebula' of 2020 from Astronomy Picture Of The Day. I wonder what APOD's cooking this year?

The Great Turkey Nebula Imagination Credit & Copyright:Eric Coles

Explanation: Surprisingly reminiscent of The Great Nebula in Orion, The Great Turkey Nebula spans this creative field of view. Of course if it were the Orion Nebula it would be our closest large stellar nursery, found at the edge of a large molecular cloud a mere 1,500 light-years away. Also known as M42, the Orion Nebula is visible to the eye as the middle "star" in the sword of Orion the Hunter, a constellation now rising in planet Earth's evening skies. Stellar winds from clusters of newborn stars scattered throughout the Orion Nebula sculpt its ridges and cavities seen in familiar in telescopic images. Much larger than any bird you might be cooking, this Great Turkey Nebula was imagined to be similar in size to the Orion Nebula, about 13 light-years across. Stay safe and well. (APOD, 2020 Nov. 16).

Source: https://apod.nasa.gov/apod/ap201126.html

2023 October 23

Moon Io from Spacecraft Juno Image Credit: NASA, JPL-Caltech, SwRI, MSSS; Processing & Copyright: Ted Stryk & Fernando García Navarro

Explanation: There goes another one! Volcanoes on Jupiter’s moon Io keep erupting. To investigate, NASA’s robotic Juno spacecraft has begun a series of visits to this very strange moon. Io is about the size of Earth’s moon, but because of gravitational flexing by Jupiter and other moons, Io’s interior gets heated and its surface has become covered with volcanoes. The featured image is from last week’s flyby, passing within 12,000 kilometers above the dangerously active world. The surface of Io is covered with sulfur and frozen sulfur dioxide, making it appear yellow, orange and brown. As hoped, Juno flew by just as a volcano was erupting – with its faint plume visible near the top of the featured image. Studying Io’s volcanoes and plumes helps humanity better understand how Jupiter’s complex system of moons, rings, and auroras interact. Juno is scheduled to make two flybys of Io during the coming months that are almost 10 times closer: one in December and another in February 2024.

∞ Source: apod.nasa.gov/apod/ap231023.html

2023 October 10

Hidden Orion from Webb Image Credit & License: NASA, ESA, CSA, JWST; Processing: M. McCaughrean & S. Pearson

Explanation: The Great Nebula in Orion has hidden stars. To the unaided eye in visible light, it appears as a small fuzzy patch in the constellation of Orion. But this image was taken by the Webb Space Telescope in a representative-color composite of red and very near infrared light. It confirms with impressive detail that the Orion Nebula is a busy neighborhood of young stars, hot gas, and dark dust. The rollover image shows the same image in representative colors further into the near infrared. The power behind much of the Orion Nebula (M42) is the Trapezium - a cluster of bright stars near the nebula’s center. The diffuse and filamentary glow surrounding the bright stars is mostly heated interstellar dust. Detailed inspection of these images shows an unexpectedly large number of Jupiter-Mass Binary Objects (JuMBOs), pairs of Jupiter-mass objects which might give a clue to how stars are forming. The whole Orion Nebula cloud complex, which includes the Horsehead Nebula, will slowly disperse over the next few million years.

∞ Source: apod.nasa.gov/apod/ap231010.html

2023 October 15

An Eclipse Tree Image Credit & Copyright: Shawn Wyre

Explanation: Yes, but can your tree do this? If you look closely at the ground in the featured image, you will see many images of yesterday’s solar eclipse – created by a tree. Gaps between tree leaves act like pinhole lenses and each create a small image of the partially eclipsed Sun visible in the other direction. The image was taken in Burleson, Texas, USA. Yesterday, people across the Americas were treated to a partial eclipse of the Sun, when the Moon moves in front of part of the Sun. People in a narrow band of Earth were treated to an annular eclipse, also called a ring-of-fire eclipse, when the Moon becomes completely engulfed by the Sun and sunlight streams around all of the Moon’s edges. In answer to the lede question, your tree not only can do this, but will do it every time that a visible solar eclipse passes overhead. Next April 8, a deeper, total solar eclipse will move across North America.

∞ Source: apod.nasa.gov/apod/ap231015.html

Young Stars, Stellar Jets via NASA https://ift.tt/mUE9hQK

2023 October 18

Dust and the Western Veil Nebula Image Credit & Copyright: Jiang Wu

Explanation: It’s so big it is easy to miss. The entire Veil Nebula spans six times the diameter of the full moon, but is so dim you need binoculars to see it. The nebula was created about 15,000 years ago when a star in the constellation of the Swan (Cygnus) exploded. The spectacular explosion would have appeared brighter than even Venus for a week - but there is no known record of it. Pictured is the western edge of the still-expanding gas cloud. Notable gas filaments include the Witch’s Broom Nebula on the upper left near the bright foreground star 52 Cygni, and Fleming’s Triangular Wisp (formerly known as Pickering’s Triangle) running diagonally up the image middle. What is rarely imaged – but seen in the featured long exposure across many color bands – is the reflecting brown dust that runs vertically up the image left, dust likely created in the cool atmospheres of massive stars.

∞ Source: apod.nasa.gov/apod/ap231018.html

2023 October 17

PDS 70: Disk, Planets, and Moons Image Credit: ALMA (ESO/NAOJ/NRAO); M. Benisty et al.

Explanation: It’s not the big ring that’s attracting the most attention. Although the big planet-forming ring around the star PDS 70 is clearly imaged and itself quite interesting. It’s also not the planet on the right, just inside the big disk, that’s being talked about the most. Although the planet PDS 70c is a newly formed and, interestingly, similar in size and mass to Jupiter. It’s the fuzzy patch around the planet PDS 70c that’s causing the commotion. That fuzzy patch is thought to be a dusty disk that is now forming into moons – and that had never been seen before. The featured image was taken in 2021 by the Atacama Large Millimeter Array (ALMA) of 66 radio telescopes in the high Atacama Desert of northern Chile. Based on ALMA data, astronomers infer that the moon-forming exoplanetary disk has a radius similar to our Earth’s orbit, and may one day form three or so Luna-sized moons – not very different from our Jupiter’s four.

∞ Source: apod.nasa.gov/apod/ap231017.html

Tulip Nebula in Cygnus