A New Image From Webb Shows Galaxy NGC 1365, Known to Have an Actively Feeding Supermassive Black Hole

The barred spiral galaxy NGC 1365. Credit: NASA/JPL-Caltech/Judy Schmidt

The James Webb Space Telescope continues to deliver stunning images of the Universe, demonstrating that the years of development and delays were well worth the wait! The latest comes from Judy Schmidt (aka. Geckzilla, SpaceGeck), an astrophotographer who processed an image taken by Webb of the barred spiral galaxy NGC 1365. Also known as the Great Barred Spiral Galaxy, NGC 1365 is a double-barred spiral galaxy consisting of a long bar and a smaller barred structure located about 56 million light-years away in the southern constellation Fornax.

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Messier 96 – the NGC 3368 Spiral Galaxy

This new NASA/ESA Hubble Space Telescope shows Messier 96, a spiral galaxy just over 35 million light-years away in the constellation of Leo (The Lion). It is of about the same mass and size as the Milky Way. It was first discovered by astronomer Pierre Méchain in 1781, and added to Charles Messier’s famous catalogue of astronomical objects just four days later. The galaxy resembles a giant maelstrom of glowing gas, rippled with dark dust that swirls inwards towards the nucleus. Messier 96 is a very asymmetric galaxy; its dust and gas is unevenly spread throughout its weak spiral arms, and its core is not exactly at the galactic centre. Its arms are also asymmetrical, thought to have been influenced by the gravitational pull of other galaxies within the same group as Messier 96. This group, named the M96 Group, also includes the bright galaxies Messier 105 and Messier 95, as well as a number of smaller and fainter galaxies. It is the nearest group containing both bright spirals and a bright elliptical galaxy (Messier 105).

Welcome back to Messier Monday! Today, we continue in our tribute to our dear friend, Tammy Plotner, by looking at the barred spiral galaxy known as Messier 95!

During the 18th century, famed French astronomer Charles Messier noticed the presence of several “nebulous objects” while surveying the night sky. Originally mistaking these objects for comets, he began to catalog them so that others would not make the same mistake. Today, the resulting list (known as the Messier Catalog) includes over 100 objects and is one of the most influential catalogs of Deep Space Objects.

One of these objects is Messier 96 (M96, NGC 3368), an intermediate double-sparred spiral galaxy located about 31 million light-years away in the constellation Leo. This galaxy is known for having a small inner bulge through the core, an outer bulge, and is comparable in size to the Milky Way. M96 is the brightest member of the Leo I group of galaxies (which includes M95, M105, and a number of fainter galaxies), hence why it’s also known as the M96 group.

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The Milky Way’s Central bar Spin-Rate is Slowing Down Thanks to Dark Matter

Credit: Data: ESA/Gaia/DPAC, A. Khalatyan(AIP) & StarHorse team; Galaxy map: NASA/JPL-Caltech/R. Hurt (SSC/Caltech)

If it were’t for an enormous halo of dark matter enveloping our galaxy, the spin-rate of our central bar should stay pretty constant. But researchers have recently inferred that it has slowed down by almost 25% since its formation, a clear sign of the presence of dark matter.

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Barred Spiral Galaxy NGC 2608, Surrounded by Many Many Other Galaxies

Looking deep into the Universe, the NASA/ESA Hubble Space Telescope catches a passing glimpse of the numerous arm-like structures that sweep around this barred spiral galaxy, known as NGC 2608. Appearing as a slightly stretched, smaller version of our Milky Way, the peppered blue and red spiral arms are anchored together by the prominent horizontal central bar of the galaxy. In Hubble photos, bright Milky Way stars will sometimes appear as pinpoints of light with prominent lens flares. A star with these features is seen in the lower right corner of the image, and another can be spotted just above the pale centre of the galaxy. The majority of the fainter points around NGC 2608, however, lack these features, and upon closer inspection they are revealed to be thousands of distant galaxies. NGC 2608 is just one among an uncountable number of kindred structures. Similar expanses of galaxies can be observed in other Hubble images such as the Hubble Deep Field which recorded over 3000 galaxies in one field of view.

Meet NGC 2608, a barred spiral galaxy about 93 million light years away, in the constellation Cancer. Also called Arp 12, it’s about 62,000 light years across, smaller than the Milky Way by a fair margin. The Hubble Space Telescope captured this image with its Wide-Field Camera 3 (WFC3).

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Barred Spiral NGC 3895 Captured by Hubble

Far away in the Ursa Major constellation is a swirling galaxy that would not look out of place on a coffee made by a starry-eyed barista. NGC 3895 is a barred spiral galaxy that was first spotted by William Herschel in 1790 and was later observed by the NASA/ESA Hubble Space Telescope. Hubble's orbit high above the Earth's distorting atmosphere allows astronomers to make the very high resolution observations that are essential to opening new windows on planets, stars and galaxies — such as this beautiful view of NGC 3895. The telescope is positioned approximately 570 km above the ground, where it whirls around Earth at 28 000 kilometres per hour and takes 96 minutes to complete one orbit. 

NGC 3895 is a barred spiral galaxy in the Ursa Major constellation. It’s about 145 million light years away from our home, the Milky Way, and its diameter is about 45,000 light years. William Herschel discovered it way back in 1790.

Now the Hubble Space Telescope has given us another gorgeous image of it. Thanks Hubble!

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Hubble Sees a Galaxy With Spiral Arms, Surrounded by Other Spiral Arms

Credit: NASA/ESA/HST

Even after thirty years of faithful service, the Hubble Space Telescope continues to reveal truly fascinating things about our Universe. This includes the image (shown at top) taken of the astronomical feature known as NGC 2273, a barred spiral galaxy similar to the Milky Way. However, upon closer inspection, the image reveals that the spiral arms of this galaxy contain a second set of spiral arms.

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Gaia Mission is Mapping Out the Bar at the Center of the Milky Way

Credit: Data: ESA/Gaia/DPAC, A. Khalatyan(AIP) & StarHorse team; Galaxy map: NASA/JPL-Caltech/R. Hurt (SSC/Caltech)

Despite the many advancements made in the field of astronomy, astronomers still struggle to get an accurate assessment of the Milky Way Galaxy. Because we are embedded in its disk, it is much more difficult to assess its size, structure, and extent – unlike galaxies located millions (or billions) of light-years away. Luckily, thanks to improved instruments and tireless efforts, progress is being made all the time.

For instance, a team of astronomers recently combined the latest data obtained by the ESA’s Gaia observatory with the infrared and optical observations of other telescopes to start mapping the bar-shaped collection of stars at the center of our Milky Way. This constitutes the first time in history that astronomers have been able to make direct measurements of this barred structure.

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Perfect Example of a Barred Spiral Galaxy, Seen Face On. This is What Our Milky Way Might Look Like

This striking image was taken by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3, a powerful instrument installed on the telescope in 2009. WFC3 is responsible for many of Hubble’s most breathtaking and iconic photographs, including Pictures of the Week. Shown here, NGC 7773 is a beautiful example of a barred spiral galaxy. A luminous bar-shaped structure cuts prominently through the galaxy's bright core, extending to the inner boundary of NGC 7773's sweeping, pinwheel-like spiral arms. Astronomers think that these bar structures emerge later in the lifetime of a galaxy, as star-forming material makes its way towards the galactic centre — younger spirals do not feature barred structures as often as older spirals do, suggesting that bars are a sign of galactic maturity. They are also thought to act as stellar nurseries, as they gleam brightly with copious numbers of youthful stars. Our galaxy, the Milky Way, is thought to be a barred spiral like NGC 7773. By studying galactic specimens such as NGC 7773 throughout the Universe, researchers hope to learn more about the processes that have shaped — and continue to shape — our cosmic home.

The Hubble Space Telescope has given us a beautiful image of the barred spiral galaxy NGC 7773. This is a classic galaxy of this type, and highlights the bright bar of concentrated stars that anchors the galaxy’s stately spiral arms. It was captured with the Hubble’s workhorse Wide Field Camera 3 (WFC3.)

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Messier 58 – the NGC 4579 Barred Spiral Galaxy

The galaxies of Messier 58, Messier 59, Messier 60, Messier 87, Messier 89 and Messier 90. Credit: Wikisky

Welcome back to Messier Monday! Today, we continue in our tribute to our dear friend, Tammy Plotner, by looking at the barred spiral galaxy, Messier 58.

In the 18th century, while searching the night sky for comets, French astronomer Charles Messier kept noting the presence of fixed, diffuse objects in the night sky. In time, he would come to compile a list of approximately 100 of these objects, with the purpose of making sure that astronomers did not mistake them for comets. However, this list – known as the Messier Catalog – would go on to serve a more important function, becoming one of the first catalogs of Deep Sky Objects.

One of these objects is the intermediate barred spiral galaxy known as Messier 58, which is located approximately 68 million light years away in the Virgo constellation. In addition to being one of just four barred spiral galaxies in the Messier Catalog, it is also one of the brightest galaxies in the Virgo Supercluster. Due to its proximity in the sky to other objects in the Virgo Galaxy Field, it can be seen only with the help of a telescope or a pair of large binoculars.

Description:

This beautiful old barred spiral galaxy located approximately 68 million light-years from Earth. Although it might appear pretty plain, it has some great things going for it… namely an active galactic nucleus. As Marcella Contini indicated in a 2004 study:

“We have modelled the low-luminosity active galactic nuclei (AGN) NGC 4579 by explaining both the continuum and the line spectra observed with different apertures. It was found that the nuclear emission is dominated by an AGN such that the flux from the active centre (AC) is relatively low compared with that of the narrow emission-line region (NLR) of Seyfert galaxies. However, the contribution of a young starburst cannot be neglected, as well as that of shock-dominated clouds with velocities of 100, 300 and 500kms-1. A small contribution from an older starburst with an age of 4.5 Myr, probably located in the external nuclear region, is also found. HII regions appear in the extended regions, where radiation and shock-dominated clouds prevail.

“The continuum SED of NGC 4579 is characterized by the strong flux from an old stellar population. Emissions in the radio range show synchrotron radiation from the base of the jet outflowing from the accretion disc within 0.1 pc from the active centre. Radio emission within intermediate distances is explained by the bremsstrahlung from gas downstream of low-velocity shocks reached by a relatively low radiation flux from the AC. In extended regions the radio emission is synchrotron radiation created by the Fermi mechanism at the shock front. The shocks are created by collision of clouds with the jet. All types of emissions observed at different radius from the centre can be reconciled with the presence of the jet.”

The Messier 58 barred spiral galaxy. Credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona

Yet where is this gas traveling to and why? According to 2014 study by S. Garcia-Burillo (et al):

“We created a complete gravity torque map of the disk of the LINER/Seyfert 1.9 galaxy NGC 4579. We quantify the efficiency of angular momentum transport and search for signatures of secular evolution in the fueling process from r ~ 15 kpc down to the inner r ~ 50 pc around the active galactic nucleus (AGN). The derived gravity torque budget in NGC 4579 shows that inward gas flow is occurring on different spatial scales in the disk. In the outer disk, the decoupling of the spiral allows the gas to efficiently populate the UHR region, and thus produce net gas inflow on intermediate scales. The co rotation barrier seems to be overcome by secular evolution processes. The gas in the inner disk is efficiently funneled by gravity torques down to r ~ 300 pc. Closer to the AGN, gas feels negative torques due to the combined action of the large-scale bar and the inner oval. The two m=2 modes act in concert to produce net gas inflow down to r ~ 50 pc, providing clear smoking gun evidence of inward gas transport on short dynamical timescales.”

What causes inward transport of gases? Why, a massive gravity pull of course. And what could be more gravitational attractive than a black hole! As Eliot Quataert (et al) indicated in their 1999 study:

“M81 and NGC 4579 are two of the few low-luminosity active galactic nuclei which have an estimated mass for the central black hole, detected hard X-ray emission, and detected optical/UV emission. In contrast to the canonical “big blue bump,” both have optical/UV spectra which decrease with increasing frequency in a plot. Barring significant reddening by dust and/or large errors in the black hole mass estimates, the optical/UV spectra of these systems require that the inner edge of a geometrically thin, optically thick, accretion disk lies at roughly 100 Schwarzschild radii. The observed X-ray radiation can be explained by an optically thin, two temperature, advection-dominated accretion flow at smaller radii.”

Galaxy NGC 4579 was captured by the Spitzer Infrared Nearby Galaxy Survey (SINGS) Legacy Project using the Spitzer Space Telescope’s Infrared Array Camera (IRAC). In this image, the red structures are areas where gas and dust are thought to be forming new stars, while the blue light comes from mature stars. This SINGS image is a four-channel, false-color composite, where blue indicates emission at 3.6 microns, green corresponds to 4.5 microns, and red to 5.8 and 8.0 microns. The contribution from starlight (measured at 3.6 microns) in this picture has been subtracted from the 5.8 and 8 micron images to enhance the visibility of the dust features.

Messier 58 (NGC 4579), as imaged by the Spitzer Infrared Nearby Galaxy Survey (SINGS) Legacy Project using the Spitzer Space Telescope’s Infrared Array Camera (IRAC). Credit: NASA/JPL-Caltech/R. Kennicutt (University of Arizona) and the SINGS Team

History of Observation:

When Charles Messier discovered this one on April 15, 1779, I’m sure he didn’t know he was looking back into time when he wrote:

“Very faint nebula discovered in Virgo, almost on the same parallel as Epsilon, 3rd mag. The slightest light for illuminating the micrometer wires makes it disappear. M. Messier reported it on the chart of the Comet of 1779, which is located in the volume of the Academy for the same year.”

Messier 58 may not have been a comet, but it certainly was another distant cousin of our own Milky Way!

Locating Messier 58:

Finding M58 requires a telescope or large binoculars, and lots of patience. Because the Virgo Galaxy field contains so many galaxies which can easily be misidentified, it is sometimes easier to “hop” from one galaxy to the next! In this case, we need to start by locating bright Vindemiatrix (Epsilon Virginis) almost due east of Denebola. Let’s hop four and a half degrees west and a shade north of Epsilon to locate one of the largest elliptical galaxies presently known – M60.

At a little brighter than magnitude 9, this galaxy could be spotted with binoculars, but stick with your telescope. In the same low power field (depending on aperture size) you may also note faint NGC 4647 which only appears to be interacting with M60. Also in the field to the west (the direction of drift) is our next Messier, bright cored elliptical M59. Now we will need to continue about an average eyepiece field of view, or a degree further west of this group to bring you to our “galactic twin”, fainter M58.

The location of M58, in the direction of the Virgo constellation. Credit: IAU

In a smaller telescope, do not expect to see much. What will appear at low power is a tiny egg-shaped patch of contrast change. As aperture increases, so does detail and a bright nucleus will begin to appear as you move into the 4-6″ size range and dark sky locations. As with all galaxies, dark skies are a must!

And here are the quick facts on this object to help you get started:

Object Name: Messier 58
Alternative Designations: M58, NGC 4579
Object Type: SBc Galaxy
Constellation: Virgo
Right Ascension: 12 : 37.7 (h:m)
Declination: +11 : 49 (deg:m)
Distance: 60000 (kly)
Visual Brightness: 9.7 (mag)
Apparent Dimension: 5.5×4.5 (arc min)

We have written many interesting articles about Messier Objects here at Universe Today. Here’s Tammy Plotner’s Introduction to the Messier ObjectsM1 – The Crab Nebula, and David Dickison’s articles on the 2013 and 2014 Messier Marathons.

Be to sure to check out our complete Messier Catalog. And for more information, check out the SEDS Messier Database.

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