Pic of the Week: The Indescribable NGC 2775

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Image (Credit): NGC 2775, which is 67 million light-years away, as captured by the NASA/ESA Hubble Space Telescope. (ESA/Hubble & NASA, F. Belfiore, J. Lee and the PHANGS-HST Team)

This week’s image is from the NASA/European Space Agency (ESA) Hubble Space Telescope. It shows the odd galaxy NGC 2275 that is hard to describe. Is it an elliptical galaxy, a spiral galaxy, or something else?

The ESA weighs in on the issue below:

NGC 2775 sports a smooth, featureless centre that is devoid of gas, resembling an elliptical galaxy. It also has a dusty ring with patchy star clusters, like a spiral galaxy. Which is it, then: spiral or elliptical — or neither?

Because we can only view NGC 2775 from one angle, it’s difficult to say for sure. Some researchers have classified NGC 2775 as a spiral galaxy because of its feathery ring of stars and dust, while others have classified it as a lenticular galaxy. Lenticular galaxies have features common to both spiral and elliptical galaxies.

It’s not yet known exactly how lenticular galaxies come to be, and they might form in a variety of ways. Lenticular galaxies might be spiral galaxies that have merged with other galaxies, or that have mostly run out of star-forming gas and lost their prominent spiral arms. They also might have started out more similar to elliptical galaxies, then collected gas into a disk around them.

Some evidence suggests that NGC 2775 has merged with other galaxies in the past. Invisible in this Hubble image, NGC 2775 has a tail of hydrogen gas that stretches almost 100 000 light-years around the galaxy. This faint tail could be the remnant of one or more galaxies that wandered too close to NGC 2775 before being stretched apart and absorbed. If NGC 2775 merged with other galaxies in the past, it could explain the galaxy’s strange appearance today.

Pic of the Week: Stellar Eruption Sharpless 2-284

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Image (Credit): JWST image of stellar eruption Sh2-284. (NASA/ESA/CSA/STScI/NOAJ/Y. Cheng/J. DePasquale)

This week’s image from the James Webb Space Telescope (JWST) shows a stellar eruption called Sharpless 2-284 (or Sh2-284), which is located about 15,000 light-years away. The image provides a beautiful and delicate combination of colors.

As noted in Universe Today, Reseacher Yu Cheng stated:

We didn’t really know there was a massive star with this kind of super-jet out there before the observation. Such a spectacular outflow of molecular hydrogen from a massive star is rare in other regions of our galaxy. Massive stars, like the one found inside this cluster, have very important influences on the evolution of galaxies. Our discovery is shedding light on the formation mechanism of massive stars in low-metallicity environments, so we can use this massive star as a laboratory to study what was going on in earlier cosmic history.

Pic of the Week: The Martian Turtle

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Image (Credit): Turtle-like Martian rock formation in Jezero Crater photographed by the Preservation rover. (NASA/JPL-Caltech)

While the Preservation rover on Mars has been busy looking for signs of life in Jezero Crater, it still had time to take a few fun photos as well, including the turtle image above (see the outline of the turtle below if you cannot find it). The rover captured the picture on August 31.

Image (Credit): Outline of turtle-like Martian rock formation in Jezero Crater photographed by the Preservation rover. (NASA/JPL-Caltech)

Pic of the Week: The Butterfly Star

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Image (Credit): The protostar IRAS 04302. (ESA/Webb, NASA & CSA, M. Villenave et al.)

This week’s image comes from the James Webb Space Telescope (JWST). It shows the beginning of exoplanets about 525 light-years away. Labeled the ever appealing name of IRAS 04302+2247, or better yet the Butterfly Star, the young star with its protoplanetary disc provides astronomers with plenty of information about the development of a protostar and its solar system.

Here is more from the European Space Agency (ESA):

In stellar nurseries across the galaxy, baby stars are forming in giant clouds of cold gas. As young stars grow, the gas surrounding them collects in narrow, dusty protoplanetary discs. This sets the scene for the formation of planets, and observations of distant protoplanetary discs can help researchers understand what took place roughly 4.5 billion years ago in our own Solar System, when the Sun, Earth, and the other planets formed.

IRAS 04302+2247, or IRAS 04302 for short, is a beautiful example of a protostar – a young star that is still gathering mass from its environment – surrounded by a protoplanetary disc in which baby planets might be forming. Webb is able to measure the disc at 65 billion km across – several times the diameter of our Solar System. From Webb’s vantage point, IRAS 04302’s disc is oriented edge-on, so we see it as a narrow, dark line of dusty gas that blocks the light from the budding protostar at its centre. This dusty gas is fuel for planet formation, providing an environment within which young planets can bulk up and pack on mass.

When seen face-on, protoplanetary discs can have a variety of structures like rings, gaps and spirals. These structures can be signs of baby planets that are burrowing through the dusty disc, or they can point to phenomena unrelated to planets, like gravitational instabilities or regions where dust grains are trapped. The edge-on view of IRAS 04302’s disc shows instead the vertical structure, including how thick the dusty disk is. Dust grains migrate to the midplane of the disc, settle there and form a thin, dense layer that is conducive to planet formation; the thickness of the disc is a measure of how efficient this process has been.

The dense streak of dusty gas that runs vertically across this image cocoons IRAS 04302, blotting out its bright light such that Webb can more easily image the delicate structures around it. As a result, we’re treated to the sight of two gauzy nebulas on either side of the disc. These are reflection nebulas, illuminated by light from the central protostar reflecting off of the nebular material. Given the appearance of the two reflection nebulas, IRAS 04302 has been nicknamed the ‘Butterfly Star’.

Pic of the Week: “Blood Moon Rising Behind the City Skyscrapers”

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Image (Credit): Shortlisted image “Blood Moon Rising Behind the City Skyscrapers.” (Tianyao Yang)

ZWO’s annual Astronomy Photographer of the Year Contest recently highlighted its 2025 shortlisted images, such as the image above from photographer Tianyao Yang titled “Blood Moon Rising Behind the City Skyscrapers.”

Here is the photographer’s description of the photo:

This photograph captures a red Full Moon rising beside Shanghai’s tallest skyscrapers in Lujiazui. Taken from a distance of 26.5 km (16.5 miles) from the skyscrapers in a single exposure, this image’s alignment took five years of planning. The Full Moon appears perfectly positioned next to the illuminated skyline, creating a striking contrast. 

Check out many other images at the contest site. The winning images will be announced at a ceremony on September 11, 2025.