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James Webb Space Telescope uncovers 300 mysteriously luminous objects. Are they galaxies or something else?
This baby star's big explosion fired back: 'Nature is far more complex than humans think'
We have detected a single electron with unprecedented speed
We have detected a single electron with unprecedented speed
Milky Way and zodiacal light glow above telescopes in Chile | Space photo of the day for Aug. 15, 2025
This Is What Happens Inside Lava Planets
Some exoplanets are so close to their stars that the rock is melted. Astronomers have dozens of these lava planets, maybe more because they're challenging to confirm. New research shows how the JWST can help astronomers understand them.
3I/ATLAS Is Very Actively Releasing Water
3I/ATLAS, our third discovered interstellar visitor, has been in the news a lot lately for a whole host of reasons, and rightly so given the amount of unique scientific data different groups and telescopes have been collecting off of it. A new pre-release paper from researchers at the Auburn University Department of Physics recounts yet another interesting aspect of the new visitor - its water content.
Hubble Examines Low Brightness, High Interest Galaxy
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2 min read
Hubble Examines Low Brightness, High Interest Galaxy This NASA/ESA Hubble Space Telescope image features a portion of the spiral galaxy NGC 45. ESA/Hubble & NASA, D. Calzetti, R. Chandar; Acknowledgment: M. H. Özsaraç
This NASA/ESA Hubble Space Telescope image zooms in on the feathery spiral arms of the galaxy NGC 45, which lies just 22 million light-years away in the constellation Cetus (the Whale).
The portrait uses data drawn from two complementary observing programs. The first took a broad view of 50 nearby galaxies, leveraging Hubble’s ability to observe ultraviolet through visible into near-infrared light to study star formation in these galaxies. The second program examined many of the same nearby galaxies as the first, narrowing in on a particular wavelength of red light called H-alpha. Star-forming nebulae are powerful producers of H-alpha light, and several of these regions are visible across NGC 45 as bright pink-red patches.
These observing programs aimed to study star formation in galaxies of different sizes, structures, and degrees of isolation — and NGC 45 is a particularly interesting target. Though it may appear to be a regular spiral galaxy, NGC 45 is a remarkable type called a low surface brightness galaxy.
Low surface brightness galaxies are fainter than the night sky itself, making them incredibly difficult to detect. They appear unexpectedly faint because they have relatively few stars for the volume of gas and dark matter they carry. In the decades since astronomers serendipitously discovered the first low surface brightness galaxy in 1986, researchers have learned that 30–60% of all galaxies may fall into this category. Studying these hard-to-detect galaxies is key to understanding how galaxies form and evolve, and Hubble’s sensitive instruments are equal to the task.
Text Credit: ESA/Hubble
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Share Details Last Updated Aug 15, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms Keep Exploring Discover More Topics From Hubble
35 Years of Hubble Images
Hubble’s Night Sky Challenge
Hearing Hubble
3D Hubble Models
How Social Media Algorithms Are Changing the Way People Talk
Algorithmic social media is driving the creation of new slang at a breakneck pace. Linguist Adam Aleksic, also known as the Etymology Nerd, explains how
Hubble Examines Low Brightness, High Interest Galaxy
- Hubble Home
- Overview
- Impact & Benefits
- Science
- Observatory
- Team
- Multimedia
- News
- More
2 min read
Hubble Examines Low Brightness, High Interest Galaxy This NASA/ESA Hubble Space Telescope image features a portion of the spiral galaxy NGC 45. ESA/Hubble & NASA, D. Calzetti, R. Chandar; Acknowledgment: M. H. ÖzsaraçThis NASA/ESA Hubble Space Telescope image zooms in on the feathery spiral arms of the galaxy NGC 45, which lies just 22 million light-years away in the constellation Cetus (the Whale).
The portrait uses data drawn from two complementary observing programs. The first took a broad view of 50 nearby galaxies, leveraging Hubble’s ability to observe ultraviolet through visible into near-infrared light to study star formation in these galaxies. The second program examined many of the same nearby galaxies as the first, narrowing in on a particular wavelength of red light called H-alpha. Star-forming nebulae are powerful producers of H-alpha light, and several of these regions are visible across NGC 45 as bright pink-red patches.
These observing programs aimed to study star formation in galaxies of different sizes, structures, and degrees of isolation — and NGC 45 is a particularly interesting target. Though it may appear to be a regular spiral galaxy, NGC 45 is a remarkable type called a low surface brightness galaxy.
Low surface brightness galaxies are fainter than the night sky itself, making them incredibly difficult to detect. They appear unexpectedly faint because they have relatively few stars for the volume of gas and dark matter they carry. In the decades since astronomers serendipitously discovered the first low surface brightness galaxy in 1986, researchers have learned that 30–60% of all galaxies may fall into this category. Studying these hard-to-detect galaxies is key to understanding how galaxies form and evolve, and Hubble’s sensitive instruments are equal to the task.
Text Credit: ESA/Hubble
Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Share Details Last Updated Aug 15, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms Keep Exploring Discover More Topics From Hubble
35 Years of Hubble Images
Hubble’s Night Sky Challenge
Hearing Hubble
3D Hubble Models
Scientific American Is Older Than the Discovery of Neptune
Neptune’s discovery was a race that ended not long after this magazine came to be
Brain activity can predict whether strangers will become friends
Brain activity can predict whether strangers will become friends
Cancer-killing virus becomes more effective when shielded by bacteria
Cancer-killing virus becomes more effective when shielded by bacteria
Summer Triangle Corner: Altair
3 min read
Summer Triangle Corner: Altair A map of the asterism known as the Summer Triangle. This asterism is made up of three stars: Vega in the Lyra constellation, Altair in the Aquila constellation, and Deneb in the Cygnus constellation. Stellarium Web
Altair is the last stop on our trip around the Summer Triangle! The last star in the asterism to rise for Northern Hemisphere observers before summer begins, brilliant Altair is high overhead at sunset at the end of the season in September. Altair might be the most unusual of the three stars of the Triangle, due to its great speed: this star spins so rapidly that it appears “squished.”
Altair is the brightest star in the constellation of Aquila, the Eagle. A very bright star, Altair holds a notable place in the mythologies of cultures around the world. As discussed in a previous article, Altair represents the cowherd in the ancient tale “Cowherd and the Weaver Girl.” While described as part of an eagle by ancient peoples around the Mediterranean, it was also seen as part of an eagle by the Koori people in Australia. They saw the star itself as representing a wedge-tailed eagle, and two nearby stars as his wives, a pair of black swans. More recently, one of the first home computers was named after the star: the Altair 8800.
A rapidly spinning star darkens and exhibits a bulge at the equator, as shown by the model at left. At right, an actual CHARA interferometer image of the star Altair. NASA/NSF/Center for High Angular Resolution Astronomy/Zina Deretsky
Altair’s rapid spinning was first detected in the 1960s. The close observations that followed tested the limits of technology available to astronomers, eventually resulting in direct images of the star’s shape and surface by using a technique called interferometry, which combines the light from two or more instruments to produce a single image. Predictions about how the surface of a rapidly spinning massive star would appear held true to the observations; models predicted a squashed, almost “pumpkin-like” shape instead of a round sphere, along with a dimming effect along the widened equator, and the observations confirmed this!
This equatorial dimming is due to a phenomenon called gravity darkening. Altair is wider at the equator than it is at the poles due to centrifugal force, resulting in the star’s mass bulging outwards at the equator. This results in the denser poles of the star being hotter and brighter, and the less dense equator being cooler and therefore dimmer. This doesn’t mean that the equator of Altair or other rapidly spinning stars are actually dark, but rather that the equator is dark in comparison to the poles; this is similar in a sense to sunspots. If you were to observe a sunspot on its own, it would appear blindingly bright, but it is cooler than the surrounding plasma in the Sun and so appears dark in contrast.
As summer winds down, you can still take a Trip Around the Summer Triangle with this activity from the Night Sky Network. Mark some of the sights in and around the Summer Triangle at: bit.ly/TriangleTrip.
Originally posted by Dave Prosper: August 2020
Last Updated by Kat Troche: July 2025
Summer Triangle Corner: Altair
3 min read
Summer Triangle Corner: Altair A map of the asterism known as the Summer Triangle. This asterism is made up of three stars: Vega in the Lyra constellation, Altair in the Aquila constellation, and Deneb in the Cygnus constellation. Stellarium WebAltair is the last stop on our trip around the Summer Triangle! The last star in the asterism to rise for Northern Hemisphere observers before summer begins, brilliant Altair is high overhead at sunset at the end of the season in September. Altair might be the most unusual of the three stars of the Triangle, due to its great speed: this star spins so rapidly that it appears “squished.”
Altair is the brightest star in the constellation of Aquila, the Eagle. A very bright star, Altair holds a notable place in the mythologies of cultures around the world. As discussed in a previous article, Altair represents the cowherd in the ancient tale “Cowherd and the Weaver Girl.” While described as part of an eagle by ancient peoples around the Mediterranean, it was also seen as part of an eagle by the Koori people in Australia. They saw the star itself as representing a wedge-tailed eagle, and two nearby stars as his wives, a pair of black swans. More recently, one of the first home computers was named after the star: the Altair 8800.
A rapidly spinning star darkens and exhibits a bulge at the equator, as shown by the model at left. At right, an actual CHARA interferometer image of the star Altair. NASA/NSF/Center for High Angular Resolution Astronomy/Zina DeretskyAltair’s rapid spinning was first detected in the 1960s. The close observations that followed tested the limits of technology available to astronomers, eventually resulting in direct images of the star’s shape and surface by using a technique called interferometry, which combines the light from two or more instruments to produce a single image. Predictions about how the surface of a rapidly spinning massive star would appear held true to the observations; models predicted a squashed, almost “pumpkin-like” shape instead of a round sphere, along with a dimming effect along the widened equator, and the observations confirmed this!
This equatorial dimming is due to a phenomenon called gravity darkening. Altair is wider at the equator than it is at the poles due to centrifugal force, resulting in the star’s mass bulging outwards at the equator. This results in the denser poles of the star being hotter and brighter, and the less dense equator being cooler and therefore dimmer. This doesn’t mean that the equator of Altair or other rapidly spinning stars are actually dark, but rather that the equator is dark in comparison to the poles; this is similar in a sense to sunspots. If you were to observe a sunspot on its own, it would appear blindingly bright, but it is cooler than the surrounding plasma in the Sun and so appears dark in contrast.
As summer winds down, you can still take a Trip Around the Summer Triangle with this activity from the Night Sky Network. Mark some of the sights in and around the Summer Triangle at: bit.ly/TriangleTrip.
Originally posted by Dave Prosper: August 2020
Last Updated by Kat Troche: July 2025
What Is Experimental Archaeology? Sam Kean Explores Ancient Tools, Surgeries and Feasts in Dinner with King Tut
In his new book, Sam Kean reveals how re-creating ancient tools, techniques and traditions can unlock secrets about how our ancestors lived—and what they felt.