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50-521: Herschel Catalogue may refer to: Herschel Space Observatory catalogue of observations Catalogues published by William Herschel and Caroline Herschel Catalogue of Nebulae and Clusters of Stars catalogued by William and Caroline Herschel Catalogues published by John Herschel General Catalogue of Nebulae and Clusters of Stars , catalogued by John Herschel J.L.E. Dreyer's New General Catalogue and Index Catalogues , which expanded on

100-547: A High Throughput Heterodyne Spectroscopy mission as one of its cornerstone missions. In 1986, FIRST was adopted as this cornerstone mission. It was selected for implementation in 1993, following an industrial study in 1992–1993. The mission concept was redesigned from Earth-orbit to the Lagrangian point L2, in light of experience gained from the Infrared Space Observatory [(2.5–240 μm) 1995–1998]. In 2000, FIRST

150-500: A 3.5-metre (11.5 ft) mirror and instruments sensitive to the far infrared and submillimetre wavebands (55–672 μm). Herschel was the fourth and final cornerstone mission in the Horizon 2000 programme, following SOHO / Cluster II , XMM-Newton and Rosetta . The observatory was carried into orbit by an Ariane 5 in May 2009, reaching the second Lagrangian point (L2) of

200-540: A body of scientifically validated data. Following Herschel 's demise, some European astronomers have pushed for the joint European-Japanese SPICA far-infrared observatory project, as well as ESA's continued partnership in NASA's James Webb Space Telescope . James Webb covers the near-infrared spectrum from 0.6 to 28.5 μm, and SPICA covers the mid-to-far-infrared spectral range between 12 and 230 μm. While Herschel 's dependence on liquid helium coolant limited

250-506: A forced circulation using fans . Hydrogen is used as a high-performance gaseous coolant. Its thermal conductivity is higher than all other gases, it has high specific heat capacity , low density and therefore low viscosity , which is an advantage for rotary machines susceptible to windage losses. Hydrogen-cooled turbogenerators are currently the most common electrical generators in large power plants. Inert gases are used as coolants in gas-cooled nuclear reactors . Helium has

300-526: A low tendency to absorb neutrons and become radioactive . Carbon dioxide is used in Magnox and AGR reactors. Sulfur hexafluoride is used for cooling and insulating of some high-voltage power systems ( circuit breakers , switches , some transformers , etc.). Steam can be used where high specific heat capacity is required in gaseous form and the corrosive properties of hot water are accounted for. Some coolants are used in both liquid and gas form in

350-457: A near vacuum at a temperature of approximately 1.4 K (−272 °C). The supply of helium on board the spacecraft was a fundamental limit to the operational lifetime of the space observatory; it was originally expected to be operational for at least three years. Herschel carried three detectors: NASA developed and built the mixers, local oscillator chains and power amplifiers for this instrument. The NASA Herschel Science Center , part of

400-433: A solution of a suitable organic chemical (most often ethylene glycol , diethylene glycol , or propylene glycol ) in water, is used when the water-based coolant has to withstand temperatures below 0 °C, or when its boiling point has to be raised. Betaine is a similar coolant, with the exception that it is made from pure plant juice, and is not toxic or difficult to dispose of ecologically. Polyalkylene glycol (PAG)

450-467: A year. The galaxy, termed HFLS3 , is located at z = 6.34, originating only 880 million years after the Big Bang . Just days before the end of its mission, ESA announced that Herschel 's observations had led to the conclusion that water on Jupiter had been delivered as a result of the collision of Comet Shoemaker–Levy 9 in 1994. On 22 January 2014, ESA scientists using Herschel data reported

500-402: Is CO 2 ) - is used as a coolant replacement for cutting fluids. CO 2 can provide controlled cooling at the cutting interface such that the cutting tool and the workpiece are held at ambient temperatures. The use of CO 2 greatly extends tool life, and on most materials allows the operation to run faster. This is considered a very environmentally friendly method, especially when compared to

550-405: Is dedicated to accommodate a designated set of warm units, while taking into account the heat dissipation requirements of the different warm units, of the instruments, as well as the spacecraft. Furthermore, on both spacecraft a common design has been achieved for the avionics systems, attitude control and measurement systems (ACMS), command and data management systems (CDMS), power subsystems and

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600-552: Is different from Wikidata All article disambiguation pages All disambiguation pages Herschel Space Observatory The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA). It was active from 2009 to 2013, and was the largest infrared telescope ever launched until the launch of the James Webb Space Telescope in 2021. Herschel carries

650-518: Is frequently used in large commercial systems, and sulfur dioxide was used in early mechanical refrigerators. Carbon dioxide (R-744) is used as a working fluid in climate control systems for cars, residential air conditioning, commercial refrigeration, and vending machines. Many otherwise excellent refrigerants are phased out for environmental reasons (the CFCs due to ozone layer effects, now many of their successors face restrictions due to global warming, e.g.

700-460: Is oil in water emulsion. It has varying oil content from nil oil (synthetic coolant). This coolant can either keep its phase and stay liquid or gaseous, or can undergo a phase transition , with the latent heat adding to the cooling efficiency. The latter, when used to achieve below- ambient temperature , is more commonly known as refrigerant . Air is a common form of a coolant. Air cooling uses either convective airflow (passive cooling), or

750-515: Is performed by the attitude control computer (ACC) which is the platform for the ACMS. It is designed to fulfil the pointing and slewing requirements of the Herschel and Planck payload. The Herschel spacecraft is three-axis stabilized . The absolute pointing error needs to be less than 3.7 arc seconds. The main sensor of the line of sight in both spacecraft is the star tracker . The spacecraft, built in

800-663: Is required, e.g. some fast breeder nuclear reactors . Sodium (in sodium cooled fast reactors ) or sodium- potassium alloy NaK are frequently used; in special cases lithium can be employed. Another liquid metal used as a coolant is lead , in e.g. lead cooled fast reactors , or a lead- bismuth alloy. Some early fast neutron reactors used mercury . For certain applications the stems of automotive poppet valves may be hollow and filled with sodium to improve heat transport and transfer. For very high temperature applications, e.g. molten salt reactors or very high temperature reactors , molten salts can be used as coolants. One of

850-417: Is the best known example encountered in laboratories. The phase change may not occur at the cooled interface, but on the surface of the liquid, to where the heat is transferred by convective or forced flow. Water is the most common coolant. Its high heat capacity and low cost make it a suitable heat-transfer medium. It is usually used with additives, like corrosion inhibitors and antifreeze . Antifreeze,

900-495: Is used as high temperature, thermally stable heat transfer fluids exhibiting strong resistance to oxidation. Modern PAGs can also be non-toxic and non-hazardous. Cutting fluid is a coolant that also serves as a lubricant for metal-shaping machine tools . Oils are often used for applications where water is unsuitable. With higher boiling points than water, oils can be raised to considerably higher temperatures (above 100 degrees Celsius) without introducing high pressures within

950-459: Is used to cool nozzles of rocket engines . Waterless coolant is used as an alternative to conventional water and ethylene glycol coolants. With higher boiling points than water (around 370F), the cooling technology resists boil over. The liquid also prevents corrosion . Freons were frequently used for immersive cooling of e.g. electronics. Liquid fusible alloys can be used as coolants in applications where high temperature stability

1000-804: The Cannes Mandelieu Space Center , under Thales Alenia Space Contractorship, was successfully launched from the Guiana Space Centre in French Guiana at 13:12:02 UTC on 14 May 2009, aboard an Ariane 5 rocket, along with the Planck spacecraft , and placed on a very elliptical orbit on its way towards the second Lagrangian point . The orbit's perigee was 270.0 km (intended 270.0 ± 4.5 ), apogee 1,197,080 km (intended 1 193 622 ± 151 800 ), inclination 5.99 deg (intended 6.00 ± 0.06 ). On 14 June 2009, ESA successfully sent

1050-600: The Earth–Sun system , 1,500,000 kilometres (930,000 mi) from Earth, about two months later. Herschel is named after Sir William Herschel , the discoverer of the infrared spectrum and planet Uranus , and his sister and collaborator Caroline Herschel . The observatory was capable of seeing the coldest and dustiest objects in space; for example, cool cocoons where stars form and dusty galaxies just starting to bulk up with new stars. The observatory sifted through star-forming clouds—the "slow cookers" of star ingredients—to trace

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1100-505: The second Lagrangian point (L2) of the Earth-Sun system , 1.5 million kilometres from the Earth. On 21 July 2009, Herschel commissioning was declared successful, allowing the start of the operational phase. A formal handover of the overall responsibility of Herschel was declared from the programme manager Thomas Passvogel to the mission manager Johannes Riedinger. Herschel was instrumental in

1150-622: The Herschel Space Telescope, the second time scientists have found the molecule in space. It had been previously reported by the Odin team. An October 2011 report published in Nature states that Herschel 's measurements of deuterium levels in the comet Hartley 2 suggests that much of Earth's water could have initially come from cometary impacts. On 20 October 2011, it was reported that oceans-worth of cold water vapor had been discovered in

1200-525: The Heterodyne Receiver for OST (HERO). Coolant While the term "coolant" is commonly used in automotive and HVAC applications, in industrial processing heat-transfer fluid is one technical term more often used in high temperature as well as low-temperature manufacturing applications. The term also covers cutting fluids . Industrial cutting fluid has broadly been classified as water-soluble coolant and neat cutting fluid. Water-soluble coolant

1250-659: The Infrared Processing and Analysis Center at the California Institute of Technology, also in Pasadena, has contributed science planning and data analysis software. A common service module (SVM) was designed and built by Thales Alenia Space in its Turin plant for the Herschel and Planck missions, as they were combined into one single program. Structurally, the Herschel and Planck SVMs are very similar. Both SVMs are of octagonal shape and, for both, each panel

1300-474: The R134a). Heat pipes are a special application of refrigerants. Water is sometimes employed this way, e.g. in boiling water reactors . The phase change effect can be intentionally used, or can be detrimental. Phase-change materials use the other phase transition between solid and liquid. Liquid gases may fall here, or into refrigerants, as their temperature is often maintained by evaporation. Liquid nitrogen

1350-698: The William, Caroline, John Herschel catalogues Herschel 400 Catalogue , a subset of the Herschels' catalogues for amateur astronomers Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Herschel Catalogue . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Herschel_Catalogue&oldid=1119830381 " Category : Disambiguation pages Hidden categories: Short description

1400-430: The accretion disc of a young star. Unlike warm water vapor, previously detected near forming stars, cold water vapor would be capable of forming comets which then could bring water to inner planets, as is theorized for the origin of water on Earth . On 18 April 2013, the Herschel team announced in another Nature paper that it had located an exceptional starburst galaxy which produced over 2,000 solar masses of stars

1450-505: The battery charging and discharging. For Herschel, the solar array is fixed on the bottom part of the baffle designed to protect the cryostat from the Sun. The three-axis attitude control system maintains this baffle in direction of the Sun. The top part of this baffle is covered with optical solar reflector (OSR) mirrors reflecting 98% of the Sun's energy , avoiding heating of the cryostat. This function

1500-488: The carrier liquid enhance the heat transfer capabilities of the resulting coolant compared to the carrier liquid alone. The enhancement can be theoretically as high as 350%. The experiments however did not prove so high thermal conductivity improvements, but found significant increase of the critical heat flux of the coolants. Some significant improvements are achievable; e.g. silver nanorods of 55±12 nm diameter and 12.8 μm average length at 0.5 vol.% increased

1550-481: The command for the cryocover to open which allowed the PACS system to see the sky and transmit images in a few weeks. The lid had to remain closed until the telescope was well into space to prevent contamination. Five days later the first set of test photos, depicting M51 Group , was published by ESA. In mid-July 2009, approximately sixty days after launch, it entered a halo orbit of 800,000 km average radius around

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1600-468: The container or loop system in question. Many oils have uses encompassing heat transfer, lubrication, pressure transfer (hydraulic fluids), sometimes even fuel, or several such functions at once. Fuels are frequently used as coolants for engines. A cold fuel flows over some parts of the engine, absorbing its waste heat and being preheated before combustion. Kerosene and other jet fuels frequently serve in this role in aviation engines. Liquid hydrogen

1650-404: The design life to around three years, SPICA would have used mechanical Joule-Thomson coolers to sustain cryogenic temperatures for a longer period of time. SPICA's sensitivity was to be two orders of magnitude higher than Herschel. NASA's proposed Origins Space Telescope (OST) would also observe in the far-infrared band of light. Europe is leading the study for one of OST's five instruments,

1700-460: The detection, for the first definitive time, of water vapor on the dwarf planet , Ceres , largest object in the asteroid belt . The finding is unexpected because comets , not asteroids , are typically considered to "sprout jets and plumes". According to one of the scientists, "The lines are becoming more and more blurred between comets and asteroids." On 29 April 2013, ESA announced that Herschel 's supply of liquid helium , used to cool

1750-420: The discovery of an unknown and unexpected step in the star forming process. The initial confirmation and later verification via help from ground-based telescopes of a vast hole of empty space, previously believed to be a dark nebula , in the area of NGC 1999 shed new light in the way newly forming star regions discard the material which surround them. In July 2010 a special issue of Astronomy and Astrophysics

1800-427: The formation of the steam layer. Nanofluid with the concentration more than 5% acts like non-Newtonian fluids . In some applications, solid materials are used as coolants. The materials require high energy to vaporize; this energy is then carried away by the vaporized gases. This approach is common in spaceflight , for ablative atmospheric reentry shields and for cooling of rocket engine nozzles . The same approach

1850-466: The instruments and detectors on board, had been depleted, thus ending its mission. At the time of the announcement, Herschel was approximately 1.5 million km from Earth. Because Herschel 's orbit at the L2 point is unstable, ESA wanted to guide the craft on a known trajectory. ESA managers considered two options: The managers chose the first option because it was less costly. On 17 June 2013, Herschel

1900-836: The largest optical telescope ever deployed in space. It was made not from glass but from sintered silicon carbide . The mirror's blank was manufactured by Boostec in Tarbes , France ; ground and polished by Opteon Ltd. in Tuorla Observatory , Finland ; and coated by vacuum deposition at the Calar Alto Observatory in Spain . The light reflected by the mirror was focused onto three instruments, whose detectors were kept at temperatures below 2 K (−271 °C). The instruments were cooled with over 2,300 litres (510 imp gal; 610 US gal) of liquid helium , boiling away in

1950-615: The most powerful superconducting magnets , are reached using liquid helium . Liquid hydrogen at -250 to -265 °C can also be used as a coolant. Liquid hydrogen is also used both as a fuel and as a coolant to cool nozzles and combustion chambers of rocket engines . A new class of coolants are nanofluids which consist of a carrier liquid, such as water, dispersed with tiny nano-scale particles known as nanoparticles . Purpose-designed nanoparticles of e.g. CuO , alumina , titanium dioxide , carbon nanotubes , silica , or metals (e.g. copper , or silver nanorods ) dispersed into

2000-454: The path by which potentially life-forming molecules, such as water, form. The telescope's lifespan was governed by the amount of coolant available for its instruments; when that coolant ran out, the instruments would stop functioning correctly. At the time of its launch, operations were estimated to last 3.5 years (to around the end of 2012). It continued to operate until 29 April 2013 15:20 UTC, when Herschel ran out of coolant. NASA

2050-436: The possible combinations is the mix of sodium fluoride and sodium tetrafluoroborate (NaF-NaBF 4 ). Other choices are FLiBe and FLiNaK . Liquified gases are used as coolants for cryogenic applications, including cryo-electron microscopy , overclocking of computer processors, applications using superconductors , or extremely sensitive sensors and very low- noise amplifiers . Carbon Dioxide (chemical formula

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2100-469: The same circuit, taking advantage of the high specific latent heat of boiling/condensing phase change , the enthalpy of vaporization , in addition to the fluid's non-phase-change heat capacity . Refrigerants are coolants used for reaching low temperatures by undergoing phase change between liquid and gas. Halomethanes were frequently used, most often R-12 and R-22 , often with liquified propane or other haloalkanes like R-134a . Anhydrous ammonia

2150-422: The thermal conductivity of water by 68%, and 0.5 vol.% of silver nanorods increased thermal conductivity of ethylene glycol based coolant by 98%. Alumina nanoparticles at 0.1% can increase the critical heat flux of water by as much as 70%; the particles form rough porous surface on the cooled object, which encourages formation of new bubbles, and their hydrophilic nature then helps pushing them away, hindering

2200-471: The tracking, telemetry, and command subsystem (TT&C). All spacecraft units on the SVM are redundant. On each spacecraft, the power subsystem consists of the solar array , employing triple-junction solar cells , a battery and the power control unit (PCU). It is designed to interface with the 30 sections of each solar array, provide a regulated 28 V bus, distribute this power via protected outputs and to handle

2250-557: The use of petroleum oils as lubricants; parts remain clean and dry which often can eliminate secondary cleaning operations. Liquid nitrogen , which boils at about -196 °C (77K), is the most common and least expensive coolant in use. Liquid air is used to a lesser extent, due to its liquid oxygen content which makes it prone to cause fire or explosions when in contact with combustible materials (see oxyliquits ). Lower temperatures can be reached using liquified neon which boils at about -246 °C. The lowest temperatures, used for

2300-787: Was a partner in the Herschel mission, with US participants contributing to the mission; providing mission-enabling instrument technology and sponsoring the NASA Herschel Science Center (NHSC) at the Infrared Processing and Analysis Center and the Herschel Data Search at the Infrared Science Archive . In 1982 the Far Infrared and Sub-millimetre Telescope ( FIRST ) was proposed to ESA . The ESA long-term policy-plan "Horizon 2000", produced in 1984, called for

2350-403: Was charged with four primary areas of investigation: During the mission, Herschel "made over 35,000 scientific observations" and "amass[ed] more than 25,000 hours' worth of science data from about 600 different observing programs". The mission involved the first space observatory to cover the full far infrared and submillimetre waveband. At 3.5 metres wide (11 ft), Herschel carried

2400-449: Was fully deactivated, with its fuel tanks forcibly depleted and the onboard computer programmed to cease communications with Earth. The final command, which severed communications, was sent from European Space Operations Centre (ESOC) at 12:25 UTC. The mission's post-operations phase continued until 2017. The main tasks were consolidation and refinement of instrument calibration, to improve data quality, and data processing, to create

2450-450: Was published with 152 papers on initial results from the observatory. A second special issue of Astronomy and Astrophysics was published in October 2010 concerning the sole HIFI instrument, due its technical failure which took it down over 6 months between August 2009 and February 2010. It was reported on 1 August 2011, that molecular oxygen had been definitively confirmed in space with

2500-584: Was renamed Herschel. After being put out to tender in 2000, industrial activities began in 2001. Herschel was launched in 2009. The Herschel mission cost €1,100 million . This figure includes spacecraft and payload, launch and mission expenses, and science operations. Herschel specialised in collecting light from objects in the Solar System as well as the Milky Way and even extragalactic objects billions of light-years away, such as newborn galaxies , and

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