Welcome back to Messier Monday! Today, we continue in our homage to our dear buddy, Tammy Plotner, by taking a look at the spiral nebula called Messier 89!

Throughout the 18 th century, renowned French astronomer Charles Messier saw the existence of numerous “ambiguous things” while surveying the night sky. Initially misinterpreting these things for comets, he started to brochure them so that others would not make the very same error. Today, the resulting list (called the Messier Brochure) consists of over 100 things and is among the most prominent brochures of Deep Area Objects.

Among these things is the elliptical galaxy called Messier 89, which lies about 50 million light years from Earth in the constellation Virgo This makes it part of the Virgo Cluster, a collection of 2,000 galaxies that depend on the instructions of the Virgo and Coma Berenices constellations This galaxy is not as brilliant as some other members, that makes it rather tough to identify in little telescopes.


At some 6 million light years away, Messier 89 may not resemble much besides a round, hazy spot in the night sky, however it’s what we can’t see that makes this galaxy so uncommon. Through high level of sensitivity photography done by David Malin, M89 was the very first galaxy found to have a faint covering structure.

Virgo Cluster. Credit: Wikisky

While the 150,000 light year sized sheath is intriguing enough, it’s the truth that M89 likewise consists of a jet of product extruding through it that actually raises some eyebrows. Is it originating from a great void? Or a close encounter? As Malin described:

” Among the early successes of the photographic amplification strategy was the discovery of the strange nature of the Virgo cluster galaxy Messier 89 (NGC 4552). This galaxy looks rather typical on common photos, however it exposes a faint, extremely prolonged function on deep images such as this. In the Nature paper where this was revealed it was referred to as a jet, however it is most likely the remains of a dwarf galaxy that M89 has actually soaked up or interrupted. This paper was likewise the very first to show the presence of faint ‘shells’ around elliptical galaxies, however generality of this discovery was not acknowledged up until a little later.”

So just what triggers the jet of product? Like all the Virgo Cluster members, they’re walking around out there and running into one another. As M. Machacek (et al) showed in their 2005 research study:

” We utilize a 54.4 ks Chandra observation to study ram-pressure removing in NGC4552(M89), an elliptical galaxy in the Virgo Cluster. Chandra images in the 0.5-2 keV band reveal a sharp cutting edge in the surface area brightness 3.1 kpc north of the galaxy center, a cool (kT =0.51 ^ {+0.09} _ {-0.06} keV) tail with mean density n_e ~ 5.4 +/- 1.7 x 10 ^ {-3} cm ^ {-3} extending ~10 kpc to the south of the galaxy, and 2 3-4 kpc horns of emission extending southward far from the leading edge. These are all functions particular of supersonic ram-pressure removing of galaxy gas, due to NGC4552’s movement through the surrounding Virgo ICM. Fitting the surface area brightness profile and spectra throughout the leading edge, we discover the galaxy gas inside the edge is cooler (kT = 0.43 ^ {+0.03} _ {-0.02} keV) and denser (n_e ~ 0.010 cm ^ {-3}) than the surrounding Virgo ICM (kT = 2.2 ^ {+0.7} _ {-0.4} keV and n_e = 3.0 +/- 0.3 x 10 ^ {-4} cm ^ {-3} ). The resulting pressure ratio in between the free-streaming ICM and cluster gas at the stagnancy point is ~ 7.6 ^ {+3.4} _ {-2.0} for galaxy gas metallicities of 0.5 ^ {+0.5} _ {-0.3} Zsolar, which recommends that NGC4552 is moving supersonically through the cluster with a speed v ~ 1680 ^ {+390} _ {-220} km/s (Mach 2.2 ^ {+0.5} _ {-0.3}) at an angle xi ~ 35 +/- 7 degrees towards us with regard to the aircraft of the sky.”

Pictures of 4 SMBHs records by the Chandra X-ray Observatory and an artist’s impression of what they appear like up close. Credit: X-ray: NASA/CXC Illustration: CXC/M. Weiss

More? As scientists from the Harvard-Smithsonian Center for Astrophysics showed in 2008:

” Arise from NASA’s Chandra X-ray Observatory, integrated with brand-new theoretical computations, offer among the very best pieces of proof yet that lots of supermassive great voids are spinning exceptionally quickly. The images above program 4 out of the 9 big galaxies consisted of in the Chandra research study, each consisting of a supermassive great void in its center. These images reveal sets of substantial bubbles, or cavities, in the hot gaseous environments of the galaxies, produced in each case by jets produced by a main supermassive great void. Studying these cavities enables the power output of the jets to be computed. This sets restrictions on the spin of the great voids when integrated with theoretical designs.”

However not just does Messier 89 include a supermassive great void, however it has a mini active galactic nucleus, too. As Michelle Cappellari (et al) stated in a 1998 research study:

” The complex phenomenology revealed by the UV-bright, variable spike rst spotted with the Hubble Area Telescope (HST) at the center of the otherwise typical galaxy NGC 4552 is even more examined with both HST imaging (FOC) and spectroscopy (FOS). HST/FOC images taken in 1991, 1993, and 1996 in the near UV have actually been evaluated in an uniform style, revealing that the main spike has actually lightened up by an element 4:5 in between 1991 and 1993, and has actually reduced its luminosity by an element 2:0 in between 1993 and1996 FOS spectroscopy extending from the near UV to the red side of the optical spectrum exposes a strong UV continuum over the spectrum of the underlying galaxy, in addition to numerous emission lines in both the UV and the optical varieties. In spite of the low luminosity of the UV continuum of the spike (3 105 L ), the spike is de nitely put amongst AGNs by present diagnostics based upon the emission line strength ratios, being simply on the borderline in between Seyferts and LINERs. Line professional les are extremely broad, and both allowed and prohibited lines are best designed with a mix of broad and narrow elements, with FWHM of 3000 km s 1 and 700 km s1, respectively. This proof argues for the variable main spike being produced by a modest accretion occasion onto a main huge great void (BH), with the accreted product having actually perhaps being removed from a a star in a close y by with the BH. The 1996 broad H luminosity of this mini-AGN is 5:6 1037 erg s1, about an element of 2 less than that of the nucleus of NGC 4395, heretofore thought about to be the faintest recognized AGN.”

Messier 89 and the Virgo Cluster. Credit: Wikisky

History of Observation:

M89 was among 8 members of the Virgo Galaxy cluster found by Charles Messier on the night of March 18,1781 In his notes he composes: “Nebula without star, in Virgo, a little of range from and on the very same parallel as the nebula reported above, No.87 Its light was exceptionally faint and pale, and it is not without trouble that a person can identify it.”

By the time Sir William Herschel made it to Messier’s brochure number 89, he’s recognized what an incredible field that he ‘d found. From his notes Of the amazing circumstance of nebulae:

” The variety of substance nebulae that have actually been observed in the foregoing 3 posts [on multiple nebulae] being so substantial, it will follow, that it they owe their origin to the separating of some previous substantial nebulosities of the very same nature with those which have actually been shewn to exist at present, we may anticipate that the variety of different nebulae must far surpass the previous, which additionally these spread nebulae must be discovered not just in excellent abundance, however likewise in distance or connection of each other, according to the various degrees and scenarios of the previous diffusions of such ambiguous matter. Now this is precisely what by observation, we discover to be the state of the paradises. In the following 7 varieties we have not less than 424 nebulae.”

Although Herschel never ever released these notes, we’re magnificent delighted he put in the time to brochure the remainder of the Virgo field!

Finding Messier 89:

Begin with the base M84/ M86 pairing situated nearly precisely mid-way in between Beta Leonis (Denebola) and Epsilon Virginis (Vindemiatrix). The above map reveals rather some range in between the galaxies, however by running a “grid” pattern, you can starhop the Virgo galaxy field with ease. As soon as you have M84/ M86 in sight, move one low power eyepiece field east and hop north less than and eyepiece field for M87

Virgo constellation map. Credit and ©: Torsten Bronger

Now you comprehend how Charles Messier ran his sky patterns! Continue north for 1 or 2 eyepiece fields and after that move east by one. This must bring you to M88 Now move another field east and drop south in between 1 to 2 fields. In the eyepiece, M89 will look like a really faint round haze, while it will handle a brighter core area for bigger aperture. Since M89 nears magnitude 10, it will need a dark night.

Item Call: Messier 89
Alternative Classifications: M89, NGC 4552
Item Type: Type E0 Elliptical Galaxy
Constellation: Virgo
Right Ascension: 12: 35.7 (h: m)
Declination: +12: 33 (deg: m)
Range: 60000 (kly)
Visual Brightness: 9.8 (mag)
Evident Measurement: 4.0 (arc minutes)

We have actually composed lots of intriguing posts about Messier Objects and globular clusters here at Universe Today. Here’s Tammy Plotner’s Intro to the Messier Items, M1– The Crab Nebula, Observing Spotlight– Whatever Occurred to Messier 71?, and David Dickison’s posts on the 2013 and 2014 Messier Marathons.

Be to sure to take a look at our total Messier Brochure And for additional information, take a look at the SEDS Messier Database