"Double Rainbow over the JPO, the UK's most easterly Astronomical Observatory". - Noah the Jodrell Plank Observatory shipping consultant.
"Double Rainbow over the JPO, the UK's most easterly Astronomical Observatory". - Noah the Jodrell Plank Observatory shipping consultant.
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| Jolene's completed White and Red light Safety Solar Filter used with the JPO's Seestar S30 to capture recent images of the Solar Photosphere. |
https://www.flickr.com/photos/nightskyobserver/
https://www.flickr.com/groups/bbcskyatnight/
George received an email advising him that one of our solar images would be shown on The Sky at Night program to be broadcast on the 08 June BBC Four and subsequently made available on BBC iPlayer - 'Space Weather: The Perfect Storm'.
I have included a short and relevant video clip taken from iPlayer but would recommend those interested in 'space weather', to view the whole program, which is both informative and interesting." -Joel Cairo CEO of the Jodrell Plank Observatory.
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| Images captured from the Jodrell Plank Observatory using the 127 mm. Meade Apo Refractor and the Seestar S30. Data and image credit: Pip Stakkert. |
"The other evening, our imaging technician Pip was using the Seestar S30 to photograph the waxing gibbous lunar disc. He noticed that the 'Terminator' or 'daybreak on the Moon' was about to cross the prominent feature Sinus Iridum - The Bay of Rainbows. Sunlight had just touched the peaks of the crater walls creating the effect known as the 'golden handle'. This can just be seen top left in the bottom image". - Joel Cairo CEO of the Jodrell Plank Observatory.
Key features of Sinus Iridum - Lunar notes - from Professor G.P.T Chat visiting astrophysicist at the JPO.
Sinus Iridum
(Latin for "Bay of Rainbows") is one of the most striking
basalt-flooded impact structures on the near side of the Moon. It forms a broad
semicircular embayment on the northwestern margin of Mare Imbrium and is
enclosed by the rugged arc of the Montes Jura mountain range. To lunar
observers it appears as a near-perfect luminous crescent when illuminated at
low solar angles, making it one of the most recognizable features on the lunar
disc.
Position on the Lunar Disc
Sinus Iridum
lies at approximately 44°N latitude and 31°W longitude on the Moon's near side.
Because it occupies the northwestern sector of Mare Imbrium, it appears in the
Moon's upper-left quadrant as viewed through most astronomical telescopes that
present an upright image. The feature is roughly 240–260 km in diameter and
opens southeastward into Mare Imbrium. The enclosing Jura Mountains are
remnants of the original crater rim, rising locally several kilometres above
the mare floor.
Origin as a Large Impact Basin
Sinus Iridum
began as a major impact crater formed during the late stages of the heavy
bombardment that shaped much of the lunar crust. The impact excavated a large
bowl-shaped basin and produced an elevated rim composed largely of anorthositic
highland material. The southeastern portion of the rim was later breached and
largely buried when extensive volcanic flooding associated with Mare Imbrium
spread into the crater.
The result
is not a true bay in the terrestrial sense, but rather the flooded remains of a
large impact structure whose interior became connected to the surrounding mare
plains. The surviving rim forms the dramatic semicircular wall visible today.
Geological Composition
The floor of
Sinus Iridum consists predominantly of mare basalts emplaced during multiple
volcanic episodes. Remote-sensing studies using data from the Clementine
mission, Chandrayaan-1, the Lunar Reconnaissance Orbiter, and China's Chang'E
program show that these lavas vary in composition and age across the basin.
Key
geological characteristics include:
The
surrounding Montes Jura remain compositionally distinct from the mare floor,
consisting mainly of feldspathic highland crust excavated during the original
impact event.
Age and Volcanic History
Modern
crater-count dating reveals that Sinus Iridum experienced a prolonged history
of volcanic resurfacing rather than a single flooding event.
The oldest
exposed mare units have model ages of approximately 3.37 billion years,
corresponding to the Imbrian period. Younger lava flows continued entering the
basin from Mare Imbrium for more than two billion years afterward. Some of the
youngest recognized basaltic units have ages near 1.24 billion years,
making them among the youngest extensive mare volcanics on the Moon.
The sequence
is interpreted as repeated episodes of lava entering the partially enclosed
basin from the larger Imbrium volcanic province. Rather than being filled from
a single central vent, Sinus Iridum appears to have been resurfaced multiple
times by flows arriving from adjacent mare regions.
Tectonic Evolution
Following
emplacement of the mare basalts, the region underwent tectonic deformation
associated with cooling and subsidence of the volcanic plains.
Researchers
using data from the Japanese SELENE (Kaguya) mission and NASA's Lunar Reconnaissance
Orbiter identified wrinkle ridges and compressional structures whose formation
may have continued into relatively recent lunar history. These structures
reflect crustal shortening caused by the weight and contraction of the basaltic
fill.
Spacecraft Investigations
Several
lunar missions have studied Sinus Iridum in detail.
NASA Missions
Japanese Investigations
Chinese Investigations
Although no
spacecraft has yet landed within Sinus Iridum itself, it remains scientifically
attractive because it exposes the interaction between impact-basin formation,
mare volcanism, and tectonic deformation in a single locality.
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| Captured from the JPO and previously published on the blog |
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| Messier 3 - Globular star Cluster in the Constellation Canes Venatici. Seestar S30 in Eq mode. 1 min x 60 subs Credit: Kurt Thrust at the JPO. |
" Our dedicated team of imagers and data processors has been experimenting with the application of the astro-freeware SIRIL and has used it to good affect in increasing the dynamic range of the M3 data captured on a clear night from the JPO in May this year. 'There is gold in them there 'data reduction' hills'" - Joel Cairo CEO of the Jodrell Plank Observatory.
"These images present the globular star cluster M3 — also catalogued as Messier 3 —
suspended against a richly populated stellar background in the constellation Canes
Venatici. Captured with a Seestar S30 smart telescope from the grounds of the Jodrell
Plank Observatory under the direction of Kurt Thrust, the observation reveals
one of the Milky Way’s most celebrated globular clusters: a gravitationally
bound sphere containing roughly half a million ancient stars compressed into a
region only a few hundred light-years across.
At a
distance of approximately 34,000 light-years from Earth, M3 appears as a
concentrated stellar nucleus whose luminosity rises sharply toward an intensely
radiant core. The cluster's structure is immediately apparent: a dense central
condensation surrounded by progressively looser stellar populations that
dissolve into the surrounding galactic field. This radial distribution is the
visible signature of a system that has remained gravitationally bound for more
than eleven billion years, surviving countless passages through the Milky Way's
halo while preserving a fossil record of the Galaxy's earliest epochs.
The warm
golden and reddish tones scattered throughout the cluster arise predominantly
from evolved red giant stars nearing the final stages of stellar evolution.
Intermixed among them are hotter blue-white stars, including the enigmatic
"blue stragglers" that appear younger than the rest of the cluster
population. Their presence suggests a dynamic environment where close stellar
encounters, mergers, and mass transfer events continue to reshape individual
stars despite the cluster's immense age.
M3 is
particularly significant to modern astrophysics because it hosts an
extraordinary population of variable stars, including a large number of RR
Lyrae variables whose rhythmic pulsations provide a fundamental rung on the
cosmic distance ladder. These stars act as standard candles, enabling
astronomers to measure distances across the Milky Way and beyond with
remarkable precision. More variable stars have been identified in M3 than in
almost any other known globular cluster, making it a natural laboratory for
studies of stellar evolution and pulsation physics.
The Seestar
S30 image demonstrates how modern compact smart telescopes can resolve
individual members of a globular cluster once accessible only to larger
observatory-class instruments. The cluster's sparkling granularity is evident
across the halo, where hundreds of individual stars emerge from what appears
visually as a diffuse cloud. Each point of light represents a sun in its own
right, collectively tracing a nearly spherical stellar ecosystem orbiting far
above the plane of the Milky Way.
Seen in this
observation, M3 is not merely a beautiful celestial object but a relic from the
early Universe: an ancient stellar metropolis whose stars formed when the Milky
Way itself was still young. The image captures a moment in an ongoing cosmic
history spanning billions of years, preserving within a single frame both the
elegance of gravitational order and the immense scale of galactic time". Professor G.P.T Chat visiting Astrophysicist at the Jodrell Plank Observatory.
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| Nucleus M3 - Image Credit: night-sky/hubble-messier-catalog |
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| The Globular Star Clusters Messier 53 (top right) and NGC5053 (bottom left) Seestar S30 Credit: Kurt Thrust. |
Comparison similarities and differences between M53 and NGC5053 - By Professor G.P.T Chat visiting astrophysicist at the Jodrell Plank Observatory.
The Star Clusters
1. Messier 53 (M53 / NGC 5024)
2. NGC 5053
Notable Stars & Features
The globular
clusters Messier 53 (M53, NGC 5024) and NGC 5053 form one of the most
intriguing paired systems in the Milky Way halo. They lie in the constellation
Coma Berenices, are separated on the sky by only about one degree, and are
located at nearly the same heliocentric distance (~17–18 kpc, or ~56,000–60,000
light-years). Their proximity is not merely a line-of-sight coincidence;
observational evidence suggests tidal interaction and the presence of a stellar
bridge or extended envelope connecting the two systems.
Structural Properties
The most
striking distinction between the two clusters is their internal stellar
concentration.
M53 is a moderately concentrated,
classical globular cluster, classified as Shapley–Sawyer class V. It
possesses a dense central core and a high central stellar density, giving it a
compact, nearly spherical appearance. It contains several hundred thousand
stars and is among the more massive outer-halo globular clusters.
NGC 5053, by contrast, is a highly diffuse class
XI globular cluster, among the least centrally concentrated globulars
known. Its stellar density profile is shallow, it lacks a prominent core, and
its stars are distributed over a comparatively large volume. Dynamically, it
resembles a cluster that has experienced substantial tidal stripping and mass
loss.
In terms of
dynamical evolution, M53 appears relatively robust against Galactic tidal
forces, whereas NGC 5053 is much more vulnerable to disruption because of its
lower mass and weaker gravitational binding. The presence of tidal debris
around NGC 5053 supports this interpretation.
Stellar Populations and Metallicity
Both
clusters belong to the metal-poor halo population and are among the oldest stellar
systems in the Galaxy.
M53 has a
metallicity near [Fe/H] ≈ −2.0, indicating that its stars formed from
gas enriched by only a few generations of prior stellar evolution. Its age is
approximately 13 Gyr.
NGC 5053 is
even more chemically primitive, with metallicity estimates ranging from [Fe/H]
≈ −2.1 to −2.3, placing it among the most metal-poor globular clusters in
the Milky Way. Its stars therefore preserve an especially early record of
Galactic chemical evolution.
The chemical
abundance patterns of NGC 5053 are noteworthy because they resemble those
observed in the Sagittarius Dwarf Spheroidal Galaxy rather than in typical
Milky Way halo clusters. This has led to the hypothesis that NGC 5053 may have
originated in an accreted dwarf galaxy and was later incorporated into the
Galactic halo. Similar arguments have also been advanced for M53, suggesting
that both clusters may share an extragalactic origin.
Variable Stars and Horizontal Branch Morphology
Both
clusters are rich in RR Lyrae variables, making them important laboratories for
stellar pulsation studies and distance calibration.
M53 contains
an unusually large RR Lyrae population and is classified as an Oosterhoff II
cluster. Its horizontal branch is predominantly blue, reflecting its low metallicity
and old age. The cluster also hosts numerous blue stragglers and at least one
millisecond pulsar.
NGC 5053
likewise contains RR Lyrae stars and blue stragglers, but because the cluster
is less massive, the total number of such objects is smaller. Nevertheless, its
variable-star population has been important in constraining its evolutionary
history and distance.
Orbital and Dynamical Context
Both objects
occupy the outer Galactic halo and follow highly eccentric orbits around the
Milky Way. Their present three-dimensional separation is only a few
kiloparsecs, much smaller than typical separations among halo globular
clusters.
One of the
most interesting current research topics concerns whether the two clusters
constitute a physically associated pair. Deep photometric surveys and
spectroscopic studies have revealed:
While they
are not considered a gravitationally bound binary cluster in the strict sense,
the data indicate that they have likely undergone past tidal interactions and
may have shared a common accretion history.
Scientific Significance
From an
astrophysical perspective, M53 and NGC 5053 represent two contrasting outcomes
of globular-cluster evolution under similar environmental conditions:
|
Property |
M53 (NGC 5024) |
NGC 5053 |
|
Concentration
class |
V |
XI |
|
Structure |
Compact,
dense core |
Diffuse,
loosely bound |
|
Metallicity |
~−2.0 dex |
~−2.1 to
−2.3 dex |
|
Mass |
High |
Low |
|
Stellar
density |
High |
Very low |
|
Dynamical
state |
Relatively
intact |
Strongly
affected by tidal stripping |
|
Variable-star
population |
Rich RR
Lyrae system |
Smaller RR
Lyrae population |
|
Possible
origin |
Outer-halo/accreted
system |
Strong
candidate for dwarf-galaxy origin |
In essence, M53 is a relatively massive, dynamically resilient halo globular cluster, whereas NGC 5053 appears to be a fragile, chemically primitive remnant that may be nearing the end stages of tidal dissolution. Together they provide a valuable natural experiment for studying globular-cluster formation, Galactic accretion events, stellar dynamics, and the hierarchical assembly of the Milky Way halo.
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| Solar Photosphere 24_05_2026. Seestar S30 with a base filter film Baader White Light OD:5.00 and differing Meade colour filters |
"A while ago, whilst capturing some solar video clips with our 66mm Altair Astro Lightwave ED refractor, Kurt doubled up a Baader Film filter he had made with a red filter from his old box of Meade colour filters. He was surprised at how this enhanced the contrast between the photosphere, convection cells and faculae.
From our many posts, I am sure some of you will know how pleased we are at the JPO with the Seestar S30 we purchased over a year ago. It is a great bit of kit particularly for an observatory located next to the sea and subject to fast moving changes in the weather.
I got to wondering, whether Jolene could replicate this 'filter trick' but using a home designed 'Gizmo' for magnetically attaching in front of the Seestar's 30mm diameter objective lens.
We have recently 'invested in a new 3d printer and refurbished the 'Clean Room' so Jolene was set to complete the design and build project.
Yesterday it all came together and Kurt captured some solar video clips using different coloured filters in front of the Baader OD:5.0 white light filter film.
I was very pleased with the results and suspect different filters in different combinations may provide future surprises for Kurt and the S30. We shall be posting the 3d Printing files on Thingiverse next week under my name JoelCairo76. Feel free to download and play with this but beware this may damage and/or invalidate your Seestar and its manufacturer's warrantee or guarantee from ZWO.
Jolene's next design and build projects for the Seestar S30 will be ; proper narrow x3 band astrophotography (not dual band) and spectroscopy based. Jolene has a number of new design and build ideas, which we wish to pursue." - Joel Cairo CEO of the Jodrell Plank Observatory.
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| Data for all images captured with the Seestar S30 smart-scope from the Jodrell Plank Observatory Lowestoft. Images Credit: Kurt Thrust |
Unfortunately on the night we captured the data there was some high level thin cloud which was detrimental to image clarity.- Joel Cairo CEO of the Jodrell Plank Observatory.
"The bright stellar point visible against the thin glowing disk of NGC 5907 is a supernova: SN 2026kid, discovered in April 2026 within the edge-on spiral galaxy commonly known as the Splinter Galaxy or Knife Edge Galaxy. The galaxy lies approximately 50 million light-years away in the northern constellation Draco. Kurt wondered whether the
What appears in the Seestar image as a single bright “star” is actually the catastrophic death of a massive star that exploded tens of millions of years ago, long before humans existed. The light from that explosion has only just reached Earth. SN 2026kid is classified as a Type II supernova, meaning the progenitor star retained much of its hydrogen envelope when its core collapsed under gravity.
NGC 5907 itself is an especially striking target because we view it almost perfectly edge-on. Its narrow spindle shape and dark dust lane reveal the structure of a spiral galaxy from the side, offering a perspective similar to how an external observer might see our own Milky Way. The galaxy contains relatively little active star formation compared with many spirals, making the appearance of a bright supernova particularly noteworthy.
Astronomers are especially interested in supernovae because they are fundamental to cosmic evolution. These explosions forge and disperse heavy elements — including oxygen, calcium, silicon and iron — into interstellar space. The material expelled by ancient supernovae eventually becomes incorporated into new stars, planets, and ultimately living organisms. In a very real sense, the atoms in Earth and in our own bodies were created in stars like the one that exploded in NGC 5907.
The images also capture an important aspect of modern astronomy: scientifically useful observations are now possible with compact smart telescopes such as the Seestar S30. Amateur astronomers worldwide have been imaging SN 2026kid and monitoring how its brightness changes over time, contributing valuable observational records of this transient event.
Observed from Lowestoft, Suffolk, UK, the galaxy sits high in northern skies during spring evenings, making it well placed for long integrations even with modest aperture instruments. The combination of the delicate dust lane, the razor-thin galactic profile, and the brief appearance of a supernova creates a scene that connects human observers directly with stellar evolution on a galactic scale". Professor G.P.T Chat visiting astrophysicist at the Jodrell Plank Observatory.
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| Widefield view from the Seestar S30 in equatorial mode stack of 1 minute lights Image Credit: Kurt Thrust |