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5 Jan 2025, 03:33 UT; Spotsylvania, Virginia USA. Bortle 4.5 zone.
Celestron C8 SCT at f/10.1. Orion Atlas AZ/EQ-G mount. Mallincam DS26cTEC camera, bin 1x1, exposure 16s, single frame, Optolong L'eNhance filter, no guiding, no calibration frames, sensor -5°C. Captured in Sharpcap Pro. Processed in PixInsight and Photoshop.
IDENTIFICATION OF Rigel BC
In the absence of a plate-solved location for Rigel BC the following information was considered:
1. Positive -- Published position angle (202° East of North) is consistent with labelled BC. Per ASTAP this image does not have standard orientation, e.g. it does not show North in the standard position -- up (0°). A corrected image would be rotated 7° and flipped on the horizontal axis for standard alignment with North, which puts the labelled star near the correct position.
2. Negative -- The brightest star in the field (besides Rigel A) is magnitude 6.35 and the nearby dimmer stars are approx. magnitude 10. The image of the labelled star BC (magnitude 7.5) is between them in size (brightness) but appears closer to magnitude 10 than 6.
3. Negative -- The separation of A from labelled BC in the image is roughly estimated from the image at 1 arcmin, not the expected 0.16 arcmin (9.5 arcsec).
4. Positive -- It is consistent with other posted amateur images of Rigel A & B.
BOTTOM LINE
I have 80% confidence that Rigel BC is correctly identified in this image, but another star could be obscured in the asymmetrical flare. An occulting bar may be used to verify dim Rigel BC against its brilliant companion in a subsequent image.
Appearance: Bright light blue star (Rigel A) and dim companions (Rigel B, C, and D), with adjacent variable star λ Eri (magnitude 6.35) at 3:00 position. The severe halo/flare around Rigel may be due to the filter, and may be asymmetrical due to moderate sensor tilt in the system.
Clouds: clear
Transparency: average
Seeing: below average
Apparent Magnitude (USNO): A 0.5-0.18, BC 7.5-7.6
Separation A-BC: 9.5 arcsec
Image scale:
Moon age, illuminated: xx, xx
Azimuth: xx°
Altitude: xx°
from Wikipedia
Rigel is a blue supergiant star in the constellation of Orion. It has the Bayer designation β Orionis, which is Latinized to Beta Orionis and abbreviated Beta Ori or β Ori. Rigel is the brightest and most massive component – and the eponym – of a star system of at least four stars that appear as a single blue-white point of light to the naked eye. This system is located at a distance of approximately 860 light-years (260 pc) from the Sun.
A star of spectral type B8Ia, Rigel is 120,000 times as luminous as the Sun, and is 18 to 24 times as massive, depending on the method and assumptions used. Its radius is more than seventy times that of the Sun, and its surface temperature is 12,100 K. Due to its stellar wind, Rigel's mass-loss is estimated to be ten million times that of the Sun. With an estimated age of seven to nine million years, Rigel has exhausted its core hydrogen fuel, expanded, and cooled to become a supergiant. It is expected to end its life as a type II supernova, leaving a neutron star or a black hole as a final remnant, depending on the initial mass of the star.
Rigel varies slightly in brightness, its apparent magnitude ranging from 0.05 to 0.18. It is classified as an Alpha Cygni variable due to the amplitude and periodicity of its brightness variation, as well as its spectral type. Its intrinsic variability is caused by pulsations in its unstable atmosphere. Rigel is generally the seventh-brightest star in the night sky and the brightest star in Orion, though it is occasionally outshone by Betelgeuse, which varies over a larger range.
A triple-star system is separated from Rigel by an angle of 9.5 arc seconds. It has an apparent magnitude of 6.7, making it 1/400th as bright as Rigel. Two stars in the system can be seen by large telescopes, and the brighter of the two is a spectroscopic binary. These three stars are all blue-white main-sequence stars, each three to four times as massive as the Sun. Rigel and the triple system orbit a common center of gravity with a period estimated to be 24,000 years. The inner stars of the triple system orbit each other every 10 days, and the outer star orbits the inner pair every 63 years. A much fainter star, separated from Rigel and the others by nearly an arc minute, may be part of the same star system.
In 2016, the International Astronomical Union (IAU) included the name "Rigel" in the IAU Catalog of Star Names. According to the IAU, this proper name applies only to the primary component A of the Rigel system. The system is listed variously in historical astronomical catalogs as H II 33, Σ 668, β 555, or ADS 3823. For simplicity, Rigel's companions are referred to as Rigel B, C, and D; the IAU describes such names as "useful nicknames" that are "unofficial". In modern comprehensive catalogs, the whole multiple star system is known as WDS 05145-0812 or CCDM 05145–0812.
The designation of Rigel as β Orionis (Latinized to beta Orionis) was made by Johann Bayer in 1603. The "beta" designation is usually given to the second-brightest star in each constellation, but Rigel is almost always brighter than α Orionis (Betelgeuse). Astronomer J.B. Kaler speculated that Bayer assigned letters during a rare period when variable star Betelgeuse temporarily outshone Rigel, resulting in Betelgeuse being designated "alpha" and Rigel designated "beta". However, closer examination of Bayer's method shows that he did not strictly order the stars by brightness, but instead grouped them first by magnitude, then by declination. Rigel and Betelgeuse were both classed as first magnitude, and in Orion the stars of each class appear to have been ordered north to south.
Rigel has many other stellar designations taken from various catalogs, including the Flamsteed 19 Orionis (19 Ori), the Bright Star Catalogue entry HR 1713, and the Henry Draper Catalogue number HD 34085. These designations frequently appear in the scientific literature,[ but rarely in popular writing. Rigel is listed in the General Catalogue of Variable Stars, but since its familiar Bayer designation is used instead of creating a separate variable star designation.
Rigel is an intrinsic variable star with an apparent magnitude ranging from 0.05 to 0.18. It is typically the seventh-brightest star in the celestial sphere, excluding the Sun, although occasionally fainter than Betelgeuse. Rigel appears slightly blue-white and has a B-V color index of −0.06. It contrasts strongly with reddish Betelgeuse.
Culminating every year at midnight on 12 December, and at 9:00 pm on 24 January, Rigel is visible on winter evenings in the Northern Hemisphere and on summer evenings in the Southern Hemisphere. In the Southern Hemisphere, Rigel is the first bright star of Orion visible as the constellation rises. Correspondingly, it is also the first star of Orion to set in most of the Northern Hemisphere. The star is a vertex of the "Winter Hexagon", an asterism that includes Aldebaran, Capella, Pollux, Procyon, and Sirius. Rigel is a prominent equatorial navigation star, being easily located and readily visible in all the world's oceans (the exception is the area north of the 82nd parallel north).
Rigel's spectral type is a defining point of the classification sequence for supergiants.[36][37] The overall spectrum is typical for a late B class star, with strong absorption lines of the hydrogen Balmer series as well as neutral helium lines and some of heavier elements such as oxygen, calcium, and magnesium.[38] The luminosity class for B8 stars is estimated from the strength and narrowness of the hydrogen spectral lines, and Rigel is assigned to the bright supergiant class Ia.[39] Variations in the spectrum have resulted in the assignment of different classes to Rigel, such as B8 Ia, B8 Iab, and B8 Iae.
As early as 1888, the heliocentric radial velocity of Rigel, as estimated from the Doppler shifts of its spectral lines, was seen to vary. This was confirmed and interpreted at the time as being due to a spectroscopic companion with a period of about 22 days. The radial velocity has since been measured to vary by about 10 km/s around a mean of 21.5 km/s.
In 1933, the Hα line in Rigel's spectrum was seen to be unusually weak and shifted 0.1 nm towards shorter wavelengths, while there was a narrow emission spike about 1.5 nm to the long wavelength side of the main absorption line. This is now known as a P Cygni profile after a star that shows this feature strongly in its spectrum. It is associated with mass loss where there is simultaneously emission from a dense wind close to the star and absorption from circumstellar material expanding away from the star.
The unusual Hα line profile is observed to vary unpredictably. It is a normal absorption line around a third of the time. About a quarter of the time, it is a double-peaked line, that is, an absorption line with an emission core or an emission line with an absorption core. About a quarter of the time it has a P Cygni profile; most of the rest of the time, the line has an inverse P Cygni profile, where the emission component is on the short wavelength side of the line. Rarely, there is a pure emission Hα line. The line profile changes are interpreted as variations in the quantity and velocity of material being expelled from the star. Occasional very high-velocity outflows have been inferred, and, more rarely, infalling material. The overall picture is one of large looping structures arising from the photosphere and driven by magnetic fields.
Rigel has been known to vary in brightness since at least 1930. The small amplitude of Rigel's brightness variation requires photoelectric or CCD photometry to be reliably detected. This brightness variation has no obvious period. Observations over 18 nights in 1984 showed variations at red, blue, and yellow wavelengths of up to 0.13 magnitudes on timescales of a few hours to several days, but again no clear period. Rigel's color index varies slightly, but this is not significantly correlated with its brightness variations.
From analysis of Hipparcos satellite photometry, Rigel is identified as belonging to the Alpha Cygni class of variable stars, defined as "non-radially pulsating supergiants of the Bep–AepIa spectral types". In those spectral types, the 'e' indicates that it displays emission lines in its spectrum, while the 'p' means it has an unspecified spectral peculiarity. Alpha Cygni type variables are generally considered to be irregular or have quasi-periods. Rigel was added to the General Catalogue of Variable Stars in the 74th name-list of variable stars on the basis of the Hipparcos photometry, which showed variations with a photographic amplitude of 0.039 magnitudes and a possible period of 2.075 days. Rigel was observed with the Canadian MOST satellite for nearly 28 days in 2009. Milli-magnitude variations were observed, and gradual changes in flux suggest the presence of long-period pulsation modes.
From observations of the variable Hα spectral line, Rigel's mass-loss rate due to stellar wind is estimated be (1.5±0.4)×10−7 solar masses per year (M☉/yr)—about ten million times more than the mass-loss rate from the Sun.[52] More detailed optical and K band infrared spectroscopic observations, together with VLTI interferometry, were taken from 2006 to 2010. Analysis of the Hα and Hγ line profiles, and measurement of the regions producing the lines, show that Rigel's stellar wind varies greatly in structure and strength. Loop and arm structures were also detected within the wind. Calculations of mass loss from the Hγ line give (9.4±0.9)×10−7 M☉/yr in 2006-7 and (7.6±1.1)×10−7 M☉/yr in 2009–10. Calculations using the Hα line give lower results, around 1.5×10−7 M☉/yr. The terminal wind velocity is 300 km/s. It is estimated that Rigel has lost about three solar masses (M☉) since beginning life as a star of 24±3 M☉ seven to nine million years ago.
Rigel's distance from the Sun is somewhat uncertain, different estimates being obtained by different methods. Old estimates placed it 166 parsecs (or 541 light years) away from the Sun. The 2007 Hipparcos new reduction of Rigel's parallax is 3.78±0.34 mas, giving a distance of 863 light-years (265 parsecs) with a margin of error of about 9%. Rigel B, usually considered to be physically associated with Rigel and at the same distance, has a Gaia Data Release 3 parallax of 3.2352±0.0553 mas, suggesting a distance around 1,000 light-years (310 parsecs). However, the measurements for this object may be unreliable.
Indirect distance estimation methods have also been employed. For example, Rigel is believed to be in a region of nebulosity, its radiation illuminating several nearby clouds. Most notable of these is the 5°-long IC 2118 (Witch Head Nebula), located at an angular separation of 2.5° from the star, or a projected distance of 39 light-years (12 parsecs) away. From measures of other nebula-embedded stars, IC 2118's distance is estimated to be 949 ± 7 light-years (291 ± 2 parsecs).
Rigel is an outlying member of the Orion OB1 association, which is located at a distance of up to 1,600 light-years (500 parsecs) from Earth. It is a member of the loosely defined Taurus-Orion R1 Association, somewhat closer at 1,200 light-years (360 parsecs). Rigel is thought to be considerably closer than most of the members of Orion OB1 and the Orion Nebula. Betelgeuse and Saiph lie at a similar distance to Rigel, although Betelgeuse is a runaway star with a complex history and might have originally formed in the main body of the association.
The star system of which Rigel is a part has at least four components. Rigel (sometimes called Rigel A to distinguish from the other components) has a visual companion, which is likely a close triple-star system. A fainter star at a wider separation might be a fifth component of the Rigel system.
William Herschel discovered Rigel to be a visual double star on 1 October 1781, cataloguing it as star 33 in the "second class of double stars" in his Catalogue of Double Stars, usually abbreviated to H II 33, or as H 2 33 in the Washington Double Star Catalogue.
Friedrich Georg Wilhelm von Struve first measured the relative position of the companion in 1822, cataloguing the visual pair as Σ 668. The secondary star is often referred to as Rigel B or β Orionis B. The angular separation of Rigel B from Rigel A is 9.5 arc seconds to its south along position angle 204°. Although not particularly faint at visual magnitude 6.7, the overall difference in brightness from Rigel A (about 6.6 magnitudes or 440 times fainter) makes it a challenging target for telescope apertures smaller than 15 cm (6 in).
At Rigel's estimated distance, Rigel B's projected separation from Rigel A is over 2,200 astronomical units (AU). Since its discovery, there has been no sign of orbital motion, although both stars share a similar common proper motion. The pair would have an estimated orbital period of 24,000 years. Gaia Data Release 2 (DR2) contains a somewhat unreliable parallax for Rigel B, placing it at about 1,100 light-years (340 parsecs), further away than the Hipparcos distance for Rigel, but similar to the Taurus-Orion R1 association. There is no parallax for Rigel in Gaia DR2. The Gaia DR2 proper motions for Rigel B and the Hipparcos proper motions for Rigel are both small, although not quite the same.
In 1871, Sherburne Wesley Burnham suspected Rigel B to be a binary system, and in 1878, he resolved it into two components. This visual companion is designated as component C (Rigel C), with a measured separation from component B that varies from less than 0.1″ to around 0.3″. In 2009, speckle interferometry showed the two almost identical components separated by 0.124″, with visual magnitudes of 7.5 and 7.6, respectively. Their estimated orbital period is 63 years. Burnham listed the Rigel multiple system as β 555 in his double star catalog or BU 555 in modern use.
Component B is a double-lined spectroscopic binary system, which shows two sets of spectral lines combined within its single stellar spectrum. Periodic changes observed in relative positions of these lines indicate an orbital period of 9.86 days. The two spectroscopic components Rigel Ba and Rigel Bb cannot be resolved in optical telescopes but are known to both be hot stars of spectral type around B9. This spectroscopic binary, together with the close visual component Rigel C, is likely a physical triple-star system, although Rigel C cannot be detected in the spectrum, which is inconsistent with its observed brightness.
In 1878, Burnham found another possibly associated star of approximately 13th magnitude. He listed it as component D of β 555, although it is unclear whether it is physically related or a coincidental alignment. Its 2017 separation from Rigel was 44.5″, almost due north at a position angle of 1°.[8] Gaia DR2 finds it to be a 12th magnitude sunlike star at approximately the same distance as Rigel. Likely a K-type main-sequence star, this star would have an orbital period of around 250,000 years, if it is part of the Rigel system.
A spectroscopic companion to Rigel was reported on the basis of radial velocity variations, and its orbit was even calculated, but subsequent work suggests the star does not exist and that observed pulsations are intrinsic to Rigel itself.
Rigel is a blue supergiant that has exhausted the hydrogen fuel in its core, expanded and cooled as it moved away from the main sequence across the upper part of the Hertzsprung–Russell diagram. When it was on the main sequence, its effective temperature would have been around 30,000 K. Rigel's complex variability at visual wavelengths is caused by stellar pulsations similar to those of Deneb. Further observations of radial velocity variations indicate that it simultaneously oscillates in at least 19 non-radial modes with periods ranging from about 1.2 to 74 days.
Estimation of many physical characteristics of blue supergiant stars, including Rigel, is challenging due to their rarity and uncertainty about how far they are from the Sun. As such, their characteristics are mainly estimated from theoretical stellar evolution models. Its effective temperature can be estimated from the spectral type and color to be around 12,100 K. A mass of 21±3 M☉ at an age of 8±1 million years has been estimated by comparing evolutionary tracks, while atmospheric modeling from the spectrum gives a mass of 24±8 M☉.
Although Rigel is often considered the most luminous star within 1,000 light-years of the Sun, its energy output is poorly known. Using the Hipparcos distance of 860 light-years (264 parsecs), the estimated relative luminosity for Rigel is about 120,000 times that of the Sun (L☉), but another recently published distance of 1,170 ± 130 light-years (360 ± 40 parsecs) suggests an even higher luminosity of 219,000 L☉. Other calculations based on theoretical stellar evolutionary models of Rigel's atmosphere give luminosities anywhere between 83,000 L☉ and 363,000 L☉, while summing the spectral energy distribution from historical photometry with the Hipparcos distance suggests a luminosity as low as 61,515±11,486 L☉.
A 2018 study using the Navy Precision Optical Interferometer measured the angular diameter as 2.526 mas. After correcting for limb darkening, the angular diameter is found to be 2.606±0.009 mas, yielding a radius of 74.1+6.1−7.3 R☉. An older measurement of the angular diameter gives 2.75±0.01 mas, equivalent to a radius of 78.9 R☉ at 264 pc. These radii are calculated assuming the Hipparcos distance of 264 pc; adopting a distance of 360 pc leads to a significantly larger size. Older distance estimates were mostly far lower than modern estimates, leading to lower radius estimates; a 1922 estimate by John Stanley Plaskett gave Rigel a diameter of 25 million miles, or approximately 28.9 R☉, smaller than its neighbor Aldebaran.
Due to their closeness to each other and ambiguity of the spectrum, little is known about the intrinsic properties of the members of the Rigel BC triple system. All three stars seem to be near equally hot B-type main-sequence stars that are three to four times as massive as the Sun.
Stellar evolution models suggest the pulsations of Rigel are powered by nuclear reactions in a hydrogen-burning shell that is at least partially non-convective. These pulsations are stronger and more numerous in stars that have evolved through a red supergiant phase and then increased in temperature to again become a blue supergiant. This is due to the decreased mass and increased levels of fusion products at the surface of the star.
Rigel is likely to be fusing helium in its core. Due to strong convection of helium produced in the core while Rigel was on the main sequence and in the hydrogen-burning shell since it became a supergiant, the fraction of helium at the surface has increased from 26.6% when the star formed to 32% now. The surface abundances of carbon, nitrogen, and oxygen seen in the spectrum are compatible with a post-red supergiant star only if its internal convection zones are modeled using non-homogeneous chemical conditions known as the Ledoux Criteria.
Rigel is expected to eventually end its stellar life as a type II supernova. It is one of the closest known potential supernova progenitors to Earth, and would be expected to have a maximum apparent magnitude of around −11 (about the same brightness as a quarter Moon or around 300 times brighter than Venus ever gets). The supernova would leave behind either a black hole or a neutron star.
I just noticed this studio on the first floor of the Saltillo Lofts this morning. Why am I riding my bike when I could be doing this? Maybe I should just start with the Sexy Stretching class and see how things go.
VAMPS stands for:
Vertical Aerial Movement & Pole Studio
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The throne is positioned to face the room only during an official visit from the Pope. The Doria Pamphilj Palace was built in the 17th century for the aristocratic Doria Pamphilj family, who still own the palace and its art collection. The palace, including the Thrown Room, houses numerous Renaissance and Baroque masterpieces, including works by Caravaggio, Velázquez, and Titian.
The Province has launched the Look West: Tourism Sector Action Plan that positions tourism as a key driver of economic diversification and growth.
Learn more: news.gov.bc.ca/33418
Installation view of Re:Position.
Harbourfront Centre.
April 20 – June 16, 2013
Photography: Tom Bilenkey
Either that or he is taking his own pulse while meditating.
American White Pelican (Pelecanus erythrorhynchos)
My photos can also be found at kapturedbykala.com
Kalabalik på Tyrolen 2011 - Position Paralléle.
Image from the electronic music festival "Kalabalik på Tyrolen" 2011.
Image by by Andreas Nilsson - andreas (at) bilderna.it
The entire set available @ musik.bilderna.it/#163
If you borrow an image, please ask first - we're not ones to say no ;)
Or at least link back here and/or let us know, m'kay?
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Dover Castle’s position, commanding the shortest sea crossing between England and the Continent, has given it immense strategic importance. The chalk of Castle Hill has been shaped and reshaped over the centuries into massive earthworks, ditches and mounds. Imposing walls and towers have been raised and networks of tunnels built beneath them. King Henry II began the building of the present castle in the 1180s, and over the next 800 years its buildings and defences were adapted to meet the changing demands of weapons and warfare.
Many centuries before King Henry II began the great stone castle here in the 1180s, its spectacular site above the famous white cliffs may well have been the site of an Iron Age hillfort.
The Romans built a lighthouse – one of the best-preserved in Europe – on the heights here after they invaded in AD 43, to guide ships into the harbour. The Anglo-Saxon church beside the lighthouse was once probably part of a Saxon fortified settlement. Restored in the late 19th century by Sir George Gilbert Scott and William Butterfield, it is the largest and finest Saxon building in Kent.
Checking positions for creating the menu card. Note that to facilitate the design of the card, some margins and some instructions (dimensions) have been noted down in the notebook.
Notez que pour faciliter la création et le montage des éléments de la carte de menu, les marges et les dimentions ont été notées sur le cahier.
The Chrysler Building is an Art Deco skyscraper in New York City, located on the east side of Manhattan in the Turtle Bay area at the intersection of 42nd Street and Lexington Avenue. Standing at 319 metres (1,047 ft),[3][4] it was the world's tallest building for 11 months before it was surpassed by the Empire State Building in 1931. After the destruction of the World Trade Center, it was again the second-tallest building in New York City until December 2007, when the spire was raised on the 365.8-metre (1,200 ft) Bank of America Tower, pushing the Chrysler Building into third position. In addition, The New York Times Building which opened in 2007, is exactly level with the Chrysler Building in height.[5]
The Chrysler Building is a classic example of Art Deco architecture and considered by many contemporary architects to be one of the finest buildings in New York City. In 2007, it was ranked ninth on the List of America's Favorite Architecture by the American Institute of Architects
This is an exercise as part of the strobist blog (http://www.strobist.com) Lighting 102 online course.
Strobist info: f/14 ISO200 1/250 a 580 EX at 1/16th power on sync cable
Positioned along track to Church Farm, this FW3/28 Type 28 anti-tank gun house is sited facing north to defend the river crossing at Jude's Ferry Bridge. The gun emplacement was fitted with a pedestal and nine-bolt holdfast for a 6-pounder anti-tank gun.
The FW3/28 Type 28 is a rectangular shellproof gun house designed to house either a 2pdr or 6pdr Hotchkiss anti-tank gun. The smallest Type 28 gun house, is a single chamber design built to a shellproof standard, with external walls approximately 3ft 6in thick whilst the roof is 12in thick. Overall it approximately measures 20ft by 19ft and internally the chamber measures 13ft by 12ft. At the front of the Type 28 gun house is the low and wide embrasure for the 2pdr or 6pdr anti-tank gun. With the 2pdr gun in position the shield of the gun would have covered most of the embrasure, which measures 2ft 6in internally, stepping out to 3ft 2in by 11ft 6in on the outside, the maximum traverse of the 2pdr gun was limited to a 60° sweep.
Getting the 2pdr gun inside the gun house was through a rear opening of 6ft wide, which would be closed in with sandbags as there were no doors fitted. The large unobstructed entrance did allow the 2pdr gun to maintain it’s mobility, by allowing the gun to be moved in and out rapidly. Below the gun embrasure are three recesses in the floor, the 2pdr gun, would have been wheeled into position, then its wheels removed and the trail legs unfolded and located into the floor recesses. In cases were the Hotckiss quick fire anti-tank gun was used a pedestal with a nine bolt holdfast was added to mount the gun, in a more permanent position adding sandbags around the embrasure for added protection.
Normally each side wall has an infantry embrasure, to provide some limited protection from the enemy. However, the lack of all-round small arms fire meant that the gun house would be very vulnerable to enemy attack. The lack of forward-firing Infantry embrasures meant that it would not be possible to support the 2pdr gun with small arms fire. So to overcome the problem of the limited infantry fire support the FW3/28 gun house design was modified to produce the FW3/28a. This modification consisted of a second chamber being added to the anti-tank gun chamber, the second chamber was an infantry chamber with up to three infantry embrasures, firing to the front, rear and side. Generally, the gun houses were positioned to allow the gun to fire along fixed lines, such as enfiladingss an anti-tank ditch or a bridge. In these positions the limited traverse of the gun creates no real disadvantage and the small size of the embrasure provides greater protection for the gun and its crew.
Eastern Command: Corps and Command Stop Lines – One of three Eastern Command Corps stop lines, this one running from the River Colne in Essex via Wakes Colne and Bures, along the River Stour to Sudbury and Long Melford, and thence to Bury St. Edmunds and the River Lark at Mildenhall. Its final stretch (known now as the Command Line) was via Littleport along the line of the River Great Ouse to King's Lynn.
The VS series rack & pinion type pneumatic actuators have the following features.
> 16 actuator models, the output torque from 9Nm to 4620Nm at 6 bar air supply.
> Botom drilling complies with ISO5211/DIN3337 to match valve, interface for solenoid valve, shaft top end and top drilling for assembling accessories are in accordance with VDI/VDE3845, Namur standard and +/- 5 degree; Stroke adjustment.