"And now for something completely different"

 

The Double Quasar in the Constellation Ursa Major. Data Credit: the COAST robotic telescope, BVR filters, Tenerife. telescope.org. Open Observatories, Open University. Image Credit: Kurt Thrust at the JPO.

" I was going through the JPO archive of data obtained via Open Observatories and discovered that in February 2024, my friend Kurt Thrust had programmed the COAST robotic telescope to image two Quasars. A quasar is an extremely luminous, active galactic nucleus powered by a supermassive black hole at the center of a distant galaxy. As gas and dust fall into the black hole, they form a superheated accretion disk that emits massive amounts of energy across the electromagnetic spectrum, often outshining its host galaxy. These objects can also produce powerful jets of radiation and are among the brightest objects in the universe. The 'Double Quasar in Ursa Major, is remarkable in that in reality it is one object that appears as two because of gravitational lensing. 

The Double Quasar and Neighboring Galaxies in Ursa Major

 The Double Quasar (Q0957+561)

The object known as Q0957+561, often referred to as the Double Quasar, is one of the most celebrated examples of gravitational lensing in extragalactic astronomy. It resides in the constellation Ursa Major, at a redshift of z ≈ 1.41, corresponding to a light-travel distance of roughly 8.7 billion light-years.

What makes Q0957+561 remarkable is its appearance as two nearly identical quasar images separated by about 6 arcseconds on the sky. These twin images  are not two distinct quasars, but rather light from a single background quasar that has been gravitationally lensed by an intervening galaxy and its surrounding cluster of galaxies at z ≈ 0.36. The foreground lensing galaxy, a massive elliptical designated G1, lies directly between the two quasar images.

The Double Quasar
showing the lensing galaxy cluster
image credit: ESA/Hubble

This system provided the first confirmed case of gravitational lensing of a quasar, discovered in 1979 by Dennis Walsh, Robert Carswell, and Ray Weymann. The discovery confirmed one of the key predictions of Einstein’s general theory of relativity: that massive bodies curve spacetime sufficiently to split and magnify light from background sources.

Subsequent long-term monitoring of the Double Quasar has revealed a measurable time delay of about 417 days between variations in brightness of the two images. This delay arises because the two light paths have slightly different lengths and traverse different gravitational potentials. Measurement of this delay has been used to estimate cosmological parameters such as the Hubble constant, making Q0957+561 a cornerstone object in observational cosmology.

At the eyepiece, Q0957+561 is an extremely faint object of approximately magnitude 16.5, appearing star-like even in large amateur telescopes. Only with high-resolution imaging or long-exposure CCD observations can the twin images be resolved.

NGC 3079

Located roughly 10 arcminutes south of Q0957+561, NGC 3079 is a striking edge-on spiral galaxy in Ursa Major, at a distance of about 50 million light-years (z ≈ 0.0037). Classified as type SBc, it exhibits a strong central starburst and nuclear activity, often cited as an example of a Seyfert 2 or LINER galaxy.

High-resolution imaging reveals a prominent dust lane bisecting its stellar disk and a biconical outflow of hot gas extending several kiloparsecs from the nucleus. X-ray and radio observations indicate the presence of superbubbles and galactic-scale winds driven by intense star formation and possibly a weak active nucleus. NGC 3079 is therefore a laboratory for studying feedback processes between star formation, black hole activity, and the interstellar medium.

n small telescopes, NGC 3079 appears as a slender, elongated streak of light—an impressive edge-on system that offers a vivid contrast to the much more distant and exotic Double Quasar nearby on the sky.

 NGC 3703

Farther east in Ursa Major lies NGC 3703, a relatively faint spiral galaxy (type Sc) situated at a distance of approximately 90–100 million light-years. With an apparent magnitude near 12.8, it is considerably fainter and less studied than NGC 3079. Its disk shows loosely wound spiral arms and moderate star-forming activity. NGC 3703 belongs to the same general region of the sky as the Ursa Major Cluster of galaxies, though it may lie slightly in the background relative to the cluster’s core.

While lacking the dramatic features of NGC 3079 or the cosmological significance of the Double Quasar, NGC 3703 serves as a representative example of a normal, late-type spiral galaxy, offering a useful photometric and spectroscopic comparison to more active systems in the same constellation.

Astronomical Context

• The region of Ursa Major containing Q0957+561 and NGC 3079 is an area of considerable astrophysical diversity. Within a single degree of sky, one can observe:
• A galaxy-scale gravitational lens probing the structure of spacetime and the expansion of the universe;
• A starburst galaxy exhibiting large-scale feedback and nuclear outflows; and
• A normal spiral system representative of the quiescent star-forming population.

Together, these objects demonstrate the richness of extragalactic phenomena observable in a single patch of the northern sky — from the nearby universe of tens of millions of light-years to the deep cosmos nearly nine billion years in the past.

Distance to the Double Quasar Q0957+561

• Redshift (z): ≈ 1.41

This redshift means the light we see from the quasar left it when the universe was much younger — less than half its current age.

Using the latest ΛCDM cosmological parameters (H₀ = 70 km s⁻¹ Mpc⁻¹, Ωₘ = 0.3, ΩΛ = 0.7), we can derive several commonly used distance measures:

Distance Type	Value	Meaning
Light-travel time distance	≈ 8.7 billion light-years	How long the photons have been en route to us.
Comoving radial distance	≈ 9.3 billion light-years	The current proper distance to where the quasar is now, accounting for cosmic expansion.
Luminosity distance	≈ 10.6 billion light-years	Used in converting apparent to absolute brightness, factoring in redshift dimming.

Thus, the Double Quasar is among the most distant objects visible in amateur-sized telescopes — you are seeing it as it appeared when the universe was only about 4.5 billion years old, roughly one-third of its current age.

Foreground lens galaxy

The massive elliptical galaxy G1, which lenses the background quasar, has a redshift of z ≈ 0.36, corresponding to a light-travel time of about 4.0 billion light-years.

The geometry of these two distances — a lens about halfway between us and the quasar — is what produces the beautiful and scientifically rich double image observed as Q0957+561 A and B.

In summary:

Q0957+561 lies roughly 8.7 billion light-years away, making it one of the farthest celestial objects ever discovered by purely optical means and the first gravitationally-lensed quasar confirmed in human history."

 - Karl Segin  outreach co-ordinator at the JPO and Professor G.P.T Chat.

The Double Cluster re-visited

 

The Double Cluster - NGC 869 and NGC 884. Modded Canon 200d DSLR with Dual Band Filter and 135mm Samyang Lens.

Map Credit: freestarcharts.com

" Both Kurt and Pip have never believed that they have done the Double Cluster justice. When you look at this pair of open star clusters, through binoculars or a widefield eyepiece on  a telescope at low magnification, it is truly magnificent.  The Double Cluster, viewed through the JPO's tripod mounted 11x80mm.binoculars, is a joy to see in its jewel like appearance. If you have a pair of binoculars and it's a clear night in the Northern Hemisphere, why not try and find it between Cassiopeia and Perseus? - Joel Cairo CEO of the Jodrell Plank Observatory.

"The Double Cluster in Perseus, catalogued as NGC 869 and NGC 884, is a striking pair of young, massive open star clusters located in the Perseus arm of the Milky Way Galaxy. Situated at an approximate distance of 7,500 light-years (2.3 kpc) from Earth, the system lies within the Perseus OB1 association, an active star-forming region rich in hot, luminous stars.

Both clusters are estimated to be relatively young, with ages on the order of 12–14 million years, placing them in a comparable evolutionary stage. Their stellar populations are dominated by early-type B-class main-sequence stars and a notable complement of evolved blue and red supergiants, evidence of rapid stellar evolution in high-mass stars. Integrated spectral analyses indicate a near-solar metallicity, consistent with their origin in a typical Galactic spiral-arm environment.

The clusters are physically separated by only a few hundred light-years, suggesting a common origin from the same giant molecular cloud. Their projected angular separation on the sky is approximately 30 arcminutes (roughly the apparent diameter of the full Moon), making them easily distinguishable yet visually connected in telescopic and binocular observations.

Photometric studies of NGC 869 and NGC 884 reveal high stellar densities in their cores, with mass estimates of several thousand solar masses each, placing them among the most massive open clusters in the Milky Way. Their combined luminosity and concentration of bright, blue stars make the Double Cluster an archetypal laboratory for studying the early dynamical evolution of clustered stellar populations.

Owing to their brightness (apparent magnitudes ~+4.3 and +4.4) and their location near the Perseus–Cassiopeia border, the Double Cluster has been recognized since antiquity, though it was first catalogued systematically by Hipparchus around the 2nd century BCE. Today, the system remains a prominent observational target for both professional astrophysical research and amateur astronomy, offering insight into star cluster formation, stellar evolution, and Galactic structure". - Professor G.P.T. Chat visiting astrophysicist at the Jodrell Plank Observatory.

The Heart of the matter

 

IC 1805 and Melotte 15.

"The above images captured at the Jodrell Plank Observatory and also by the PIRATE robotic telescope on Mount Teide, Tenerife (credit telescope .org, Open Observatories, Open University) show the Heart Nebula, IC1805 in increasing detail and reducing field of vision. The top, widefield image was captured with the JPOs modded Canon 200d Camera with a Dual Band filter and a Samyang 135mm lens. The other two were captured by the PIRATE telescope with SHO filters. Pip Stakkert used a number of processing techniques to emphasise the nebulosity". - Kurt Thrust current Director of the JPO.

"The Heart Nebula (IC 1805) is a large emission nebula located in the Perseus Arm of the Milky Way, within the constellation Cassiopeia. At an estimated distance of approximately 6,000–7,500 light-years from Earth, it extends over nearly 200 light-years in diameter, making it one of the more prominent star-forming complexes in the northern sky. Its common name derives from the overall morphology of its extended H II region, which, in wide-field optical images, presents an outline reminiscent of a stylized human heart.

The nebula is primarily excited by the young stellar population of the open cluster Melotte 15, situated near the nebula’s center. This cluster, containing numerous hot O-type and early B-type stars, serves as the dominant ionizing source for the surrounding gas. The intense ultraviolet radiation emitted by these massive stars ionizes the hydrogen in the surrounding molecular cloud, producing the characteristic red glow of Hα emission. Stellar winds and radiation pressure also drive large-scale feedback processes that shape the morphology of the nebula, generating bright ridges, cavities, and dark, pillar-like structures of dense gas.

Of particular note is the brighter nebulosity concentrated near the nebula’s core. This region surrounds Melotte 15 and exhibits a higher surface brightness due to the proximity of the ionizing sources and the resulting density contrast between ionized and neutral gas. Within this core, the interplay between radiation, stellar winds, and turbulence has carved out intricate filaments and luminous fronts, where shock compression has enhanced local gas densities. These conditions are conducive to ongoing star formation: observations at infrared and radio wavelengths reveal embedded protostars and compact H II regions tracing younger generations of stellar objects still enshrouded in dust.

In summary, IC 1805 exemplifies the dual role of massive stars in galactic ecology: while their radiation and winds sculpt and erode the parent molecular cloud, they also trigger subsequent episodes of star formation. The central bright nebulosity of the Heart Nebula, therefore, represents not only a visually striking concentration of emission but also the dynamic hub of stellar feedback and continuing stellar genesis within the complex". -Professor G.P.T Chat and Karl Segin outreach coordinator at the JPO.

The Iris Reflection nebula in the constellation Cepheus

The Iris Nebula in modified SHO format. The PIRATE Robotic Telescope,Mount Teide, Teneriffe.   Data Credit: telescope.org. Open Observatories, Open University. Image Credit: Kurt Thrust.

" Kurt was feeling a little better today and so he and the JPO engineer, Jolene McSquint-Fleming, were busy remaking a diffraction grating for the Seestar S30. They decided to make a grating, which covers the full aperture of the little scope rather than  partially. It will be interesting to see whether this affects the accuracy of the scope's guidance and goto software". - Joel Cairo CEO at the JPO.

The new-recycled magnetic 50 lines/mm
full aperture grating for the Seestar 30

Spectrum produced by the above grating
using the JPO Visitor Centre door security peep hole
as an artificial star.

" If we get a clear night soon, we will try the new grating out and develop a capture process, which enables the removal of stars and hot spots, which otherwise corrupt the  target and calibration spectra". - Kurt Thrust current Director of the JPO.

" The Iris Nebula, cataloged as NGC 7023, is a bright reflection nebula located in the constellation Cepheus, approximately 1,300 light-years from Earth. It is a striking example of a dust cloud illuminated by starlight rather than by its own emission. At its center lies a young, hot star designated HD 200775, whose intense blue-white radiation reflects off surrounding interstellar dust grains. This scattering process preferentially reflects shorter wavelengths, giving the nebula its characteristic bluish hue, much like the mechanism that makes Earth’s sky appear blue.

The nebula spans roughly six light-years across and is embedded within a larger molecular cloud complex. Its structure reveals striking contrasts: bright filaments and wisps where dust strongly reflects starlight, interspersed with dark lanes where dense concentrations of material obscure illumination. Infrared observations have shown that the dust contains complex carbon-rich molecules, including polycyclic aromatic hydrocarbons (PAHs), which are thought to play a role in interstellar chemistry and may represent building blocks of more complex organic compounds.

Unlike emission nebulae, which glow due to ionized gas, the Iris Nebula remains primarily a reflection nebula because the radiation from its central star is not energetic enough to fully ionize the surrounding hydrogen gas. Instead, the nebula’s beauty lies in the interplay of light and shadow, highlighting the distribution of interstellar dust and providing astronomers with insights into the conditions of stellar nurseries". - Professor G.P.T Chat visiting astrophysicist at the Jodrell Plank Observatory.

Enlarged and cropped view of the spectacular Iris reflection Nebula

IC 5070 or the Pelican Nebula in modified SHO format

Ionization fronts and cold gas in the Pelican Nebula. Data Credit: PIRATE robotic telescope SHO filters. Mount Teide, Tenerife. telescope.org Open Observatories, Open University. Image credit: Pip Stakkert at the JPO..

"The Pelican Nebula is a goto target for Northern Hemisphere  summer astro-imagers and sits next to the North America Nebula NGC7000 in the constellation Cygnus. The above narrowband image shows the delicate interplay of light and shadow: the glowing plasma energized by young stars and the cold dark lanes marking where future stars are gestating. The visible filaments trace the ionization fronts—the boundaries between the ultraviolet-irradiated cavities and the shielded interiors of molecular clouds.

In effect, the above image is a portrait of cosmic evolution in progress: the raw interstellar medium being sculpted into stars, planetary systems, and eventually the building blocks of life itself". - Joel Cairo CEO of the Jodrell Plank Observatory.

The North America and Pelican Nebulae in the Constellation Cygnus. Image credit: Kurt Thrust at the JPO

"Our narrow band SHO image, captured with the PIRATE telescope, depicts IC 5070, more commonly known as the Pelican Nebula, a large emission nebula located in the constellation Cygnus, not far from its companion, the North America Nebula (NGC 7000). Both regions are part of an extended complex of ionized hydrogen gas (an H II region) that lies about 1,800 light-years away in the Orion Arm of our Milky Way galaxy.

What we have imaged is essentially a stellar nursery: a vast cloud of hydrogen, dust, and other trace elements undergoing active star formation. The striking forms in IC 5070—its ridges, filaments, and dark channels—arise from the interaction between intense ultraviolet radiation from nearby massive stars and the dense molecular cloud material.

Ionization and Emission

The gas in IC 5070 glows because young, hot O- and B-type stars in the region emit torrents of ultraviolet light.

This radiation strips electrons from surrounding hydrogen atoms, a process known as photoionization. When the electrons recombine with protons, they emit visible light—most notably in the red H-alpha line (656.3 nm). This is why narrowband astrophotography often reveals IC 5070 with a red or magenta dominance.

Dark Dust Lanes

The jagged black regions cutting through the glowing gas are dense molecular clouds of dust and cold gas.

These clouds absorb and scatter visible light, producing the intricate silhouetted structures that make the Pelican Nebula so recognizable. Within these dark regions, protostars are forming, hidden from optical wavelengths but detectable in infrared.

Stellar Feedback

The radiation pressure and stellar winds from massive young stars push against the molecular material, carving cavities, compressing clouds, and triggering further star formation at the boundaries of these regions.

This feedback loop is a defining characteristic of giant H II regions: they are both destroyers and creators—dissipating the nebula even as they seed new generations of stars.

Overall Context

IC 5070, along with NGC 7000, is part of a giant molecular cloud complex spanning several degrees of sky, visible in wide-field astrophotography, (see Kurt's above  image) as a grand tapestry of glowing hydrogen and sculpted dust.

Astronomers often study it as an analog for stellar nurseries in other galaxies, since its proximity gives us a clearer laboratory for understanding massive star formation and interstellar medium dynamics". -Kurt Thrust current Director of the  JPO and Professor G.P.T Chat visiting astrophysicist .

NGC 281 'The Pac-man' Nebula

 

NGC 281- Part of the Pac-man Nebula. Data Credit: PIRATE robotic telescope, SHO filters, Mount Teide, Tenerife. telescope.org. Open Observatories, Open University. Image Credit: Kurt Thrust.

The Constellation Cassiopeia (The big 'W' asterism in the Northern Sky)
A compilation - 3 pane, widefield image.
Captured with the Jodrell Plank Observatory's mini-rig : Canon 600d DSLR
with a 135mm F2 Samyang Lens all on a Star Adventurer EQ mount.
  - Image Credit: Pip Stakkert

" The weather remains poor on the East Coast and sadly Kurt has been laid low by an auto-immune disorder,consequentially, little astronomy has been pursued at the JPO. Kurt did however, enjoy an hour working upon the Pac-man data obtained via the PIRATE robotic scope on Tenerife". - Joel Cairo CEO of the JPO.

NGC 281 in detail

"The NGC 281 nebula, often nicknamed the Pacman Nebula due to its resemblance to the iconic video game character in optical images, is a large, active star-forming region located in the Perseus spiral arm of the Milky Way. Situated in the northern constellation Cassiopeia, this emission nebula lies approximately 9,200 light-years (2.8 kiloparsecs) from Earth. With an angular diameter of nearly 35 arcminutes—comparable to the size of the full Moon—it corresponds to a physical span of over 100 light-years across.

NGC 281 is classified as an H II region, a vast cloud of ionized hydrogen gas energized by the intense ultraviolet radiation from its embedded young stars. At its core lies the open star cluster IC 1590, which hosts a population of hot, massive O- and B-type stars. Among them, the O6 star HD 5005 is particularly dominant, providing much of the ionizing flux that causes the surrounding hydrogen gas to glow in vivid emission lines, especially the characteristic red Hα radiation.

The nebula’s structure is rich and complex, sculpted by stellar winds and radiation. Prominent features include dense Bok globules—cold, dark molecular clumps that appear as silhouettes against the luminous background. These globules are active nurseries where protostars are forming, their growth regulated by the interplay between self-gravity and external radiation pressure. Infrared observations from the Spitzer Space Telescope and more recent surveys with the James Webb Space Telescope (JWST) have revealed numerous young stellar objects (YSOs) and protostellar disks within NGC 281, highlighting its ongoing role as a cradle of stellar birth.

The nebula is also notable for being the site of significant molecular outflows and stellar feedback processes. Winds from the massive stars in IC 1590 compress nearby gas, triggering sequential star formation along the peripheries of the nebula—a process sometimes described as “collect and collapse.” This makes NGC 281 a textbook example for studying how massive stars regulate the evolution of their parent molecular clouds.

From an observational perspective, NGC 281 is accessible with modest amateur telescopes under dark skies, appearing as a faint glowing patch of nebulosity surrounding a small star cluster. Through long-exposure astrophotography, its intricate structure becomes clear, with reddish emission nebulae, dark dust lanes, and striking cavities carved by stellar activity.

In summary:

NGC 281 in Cassiopeia is a luminous emission nebula and star-forming complex, powered by the young cluster IC 1590. Spanning over 100 light-years, it contains dark Bok globules, active protostars, and striking examples of stellar feedback shaping the interstellar medium. Its combination of visual beauty and astrophysical richness has made it both a popular target for amateur astronomers and a significant object of study for professional astrophysics, particularly in the fields of star formation, stellar feedback, and nebular evolution". - Professor G.P.T Chat visiting astrophysicist at he Jodrell Plank Observatory.