Posted on by Evan Gough

A New Image Reveals Orion’s Flame Nebula in Infrared

The ESO has released some stunning new images of Orion’s Flame Nebula. They’re from a few years ago but are newly processed as part of the Orion cloud complex study. The images have led to discoveries in the often-observed Orion cloud complex.

Astronomers love to look at well-known objects with new telescopes because they always see something new. That’s what happened when astronomers used the new SuperCam instrument installed on the ESO’s Atacama Pathfinder Experiment (APEX.) Astronomers designed the instrument to examine molecular clouds and the star-forming regions in the Orion molecular cloud complex, among other targets.

The image is part of the APEX Large CO Heterodyne Orion Legacy Survey (ALCOHOLS). Though the image is from a few years ago, it was only recently processed and included as part of a newly-published paper.

The paper’s title is “The APEX Large CO Heterodyne Orion Legacy Survey (ALCOHOLS). I. Survey overview,” The lead author is Thomas Stanke. The paper is due to be published in the journal Astronomy and Astrophysics.

The Orion cloud complex is hundreds of light-years across and between 1300 and 1600 light-years away. It’s one of the most active star-forming regions that we can see with the naked eye and holds the closest molecular clouds to the Sun. It contains young, newly-born stars with protoplanetary disks, emission nebulae and reflection nebulae, dark nebulae, and other features. For these reasons, it’s an often-studied area of the sky, an irresistible lure for intellectually curious astronomers and astrophysicists.

As part of their observations, the team behind this work observed the Flame Nebula and other structures in its surroundings. They got good looks at the reflection nebulae Messier 78 and NGC 2071, lit up by nearby stars and other objects like expanding bubbles.

This image shows the Flame Nebula and its surroundings captured in radio waves. The image is based on observations conducted with the SuperCam instrument on the ESO-operated Atacama Pathfinder Experiment (APEX) on Chile’s Chajnantor Plateau. The Flame Nebula is the prominent feature on the left. The minor feature on the right is the reflection nebula NGC 2023. To the top right of NGC 2023, the iconic Horsehead Nebula seems to emerge heroically from the “flames.” The three objects are part of the Orion cloud, a giant gas structure located between 1300 and 1600 light-years away. The different colours indicate the velocity of the gas. The Flame Nebula and its surroundings are moving away from us, with the red clouds in the background receding faster than the yellow ones in the foreground.

In a press release announcing the study and the new images, lead author Thomas Stanke said, “As astronomers like to say, whenever there is a new telescope or instrument around, observe Orion: there will always be something new and interesting to discover!”

One of their discoveries is a small, spherical cloud that they’re calling the Cow Nebula Globule. Though it appears cometary in structure in optical light, it’s actually a round, possibly spherical cloud of gas. It’s also starless.

The team discovered the starless feature that they named the Cow Nebula Globule. It's a round starless cloud of gas in the Orion Molecular Cloud. Image Credit: Stanke et al 2021.
The team discovered the starless feature that they named the Cow Nebula Globule. It’s a round, starless cloud of gas in the Orion Molecular Cloud. Image Credit: Stanke et al 2021.

But the Flame Nebula (NGC 2024) is a highlight in these new images. It’s about 900 to 1500 light-years away, and Alnitak, the triple-star system at the eastern end of Orion’s Belt, lights it up.

This image highlights the three stars in Orion's Belt, with Alnitak on the left. Also visible are the Flame Nebula and the Horsehead Nebula. Image Credit: By Mvln - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=103648580
This image orient the viewer to the Flame Nebula’s position in Orion. It highlights the three stars in Orion’s Belt, with Alnitak on the left. Also visible are the Flame Nebula and the Horsehead Nebula. Image Credit: By Mvln – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=103648580

Flame is an emission nebula, which means that the gases are ionized by ultraviolet energy from Alnitak and emit light at different wavelengths. Like the Orion cloud complex of clouds that it’s a part of, the Flame Nebula is an active star-forming region. A cluster of young stars lies in the Flame Nebula’s center, many with protoplanetary disks. But, perhaps sadly, many of those disks may never have the chance to form planets. Hubble Telescope observations in 2021 show that the nearby young stars are eroding many of these disks with their intense radiation.

The Flame Nebula region as seen with APEX and the DSS2. APEX captured the image in the rectangle while the Digitized Sky Survey 2 (DSS2) provided the background. Image Credit: ESO/Th. Stanke & ESO/Digitized Sky Survey 2. Acknowledgement: Davide De Martin
This image shows the Flame Nebula region as seen with APEX and the DSS2. APEX captured the image in the rectangle while the Digitized Sky Survey 2 (DSS2) provided the background. Image Credit: ESO/Th. Stanke & ESO/Digitized Sky Survey 2. Acknowledgement: Davide De Martin
This spectacular visible light wide-field view of part of the famous belt of the great celestial hunter Orion shows the region of the sky around the Flame Nebula. The whole image is filled with glowing gas clouds illuminated by hot blue young stars. It was created from photographs in red and blue light forming part of the Digitized Sky Survey 2. The field of view is approximately three degrees. This image is not part of the new study but shows the Flame Nebula in a different context. The image also shows the Horsehead Nebula. Image Credit: By ESO and Digitized Sky Survey 2 - http://www.eso.org/public/images/eso0949k/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=29936747
This spectacular visible light wide-field view of part of the famous belt of the great celestial hunter Orion shows the region of the sky around the Flame Nebula. Glowing gas clouds illuminated by hot blue young stars fill the image. It was created from photographs in red and blue light forming part of the Digitized Sky Survey 2. The field of view is approximately three degrees. This image is not part of the new study but shows the Flame Nebula in a different context. The image also shows the Horsehead Nebula. Image Credit: By ESO and Digitized Sky Survey 2 – http://www.eso.org/public/images/eso0949k/, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=29936747

The Orion Complex is an intricately detailed region of space full of stars and gas and all the interplay between the two. It’s the nearest high-mass star birth region full of young stars and protostars, all fully characterized by multiple surveys, observations, and studies. This study adds more detail to all that knowledge, and the authors hope that future studies will reveal even more. The study’s conclusion says they only “scratch the surface” of what their method can expose.

But for now, we can enjoy the images.

More: