JCMT NEWSLETTER

J A M E S C L E R K M A X W E L L T E L E S C O P E

SPRING 2008 • #28

SCUBA–2 installation and integration begin

HARP/ACSIS Science Results Planetary Spectroscopy Results JCMT Newsletter, James Clerk Max- In This Issue well Telescope, is published biannu- ally and is edited by Gerald Schieven and Jonathan Kemp.

ISSN 1351–5497. Copyright © 2008 by Science and Technology Facilities Council, Joint Astronomy Centre, From the Desk of the Director (Davis & Chrysostomou) ...... 3 Hilo, except where copyright re- tained by named individual article or image authors. JCMT Science

SSUE postal address I Heavy Water in Solar–Type Protostars (Ceccarelli, Charnley, & Butner) ...... 4 James Clerk Maxwell Telescope Joint Astronomy Centre HIS Evidence of Large–Scale Outflows in the Serpens South Cluster University Park T (Matthews, Gutermuth, Bourke, Allen, Dunham, Evans, Harvey, Hatchell, & Jørgensen) ...... 5 660 North A`ohoku Place N

I Hilo, Hawai`i 96720–2700 Sulfur in the Venus Mesosphere (Sandon, Clancy, & Moiriary–Schieven) ...... 6 USA

Acid Water in Colliding Galaxies (van der Tak) ...... 7 telephone Star Formation at the Edge of the Galaxy (Brand & Wouterloot) ...... 8 +1 (808) 961 – 3756

Abundance Profile of CO in Neptune’s Atmosphere facsimile (Hesman, Davus, Matthews, & Orton) ...... 10 +1 (808) 961 – 6516

world wide web JCMT Operations http://www.jach.hawaii.edu/JCMT/

SCUBA Data on Google Earth (Simpson) ...... 9 The Joint Astronomy Centre provides services and support to enable visit- Starlink Software Collection: Humu Release (Cavanagh) ...... 11 ing and staff astronomers to under- 2 Pointing the Way: The JCMT Pointing Project (Coulson) ...... 12 take top-quality, front-line interna- tional-class research using the James Data Processing Developments ...... 13 Clerk Maxwell Telescope (JCMT) and Au Revoir (Kemp) ...... 13 the United Kingdom Infrared Tele- scope (UKIRT); to develop these fa- The Night Shift (Hoge) ...... 14 cilities in order to maintain their The Last Word (Schieven) ...... 15 position as the most advanced of their kind in the world; to operate them in the most cost effective and efficient manner on behalf of the funding agencies; and to be respon- sive to the changing needs of the contributing organizations.

The JCMT is supported by the United Kingdom’s Science and Technology Facilities Council (STFC), the Na- tional Research Council Canada (NRC), and the Netherlands Organi- zation for Scientific Research (NWO); 2008 • #28 it is overseen by the JCMT Board.

PRING The JCMT is a member of the RadioNet consortium. • S

On the front cover: SCUBA–2 installation and integra- On the rear cover: Google Sky offers SCUBA point tion at JCMT. (Also see articles on pages 3 and 14 of sources and images as a complement to its optical this issue; images courtesy Jonathan Kemp/JAC and images. (Also see Figures 1 and 2 and article on page EWSLETTER Jim Hoge/JAC.) 9 of this issue.)

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From the Desk of the Director EWSLETTER

Professor Gary Davis (Director JCMT) & Antonio Chrysostomou (Associate Director JCMT)

• S SCUBA–2 is in Status page (http:// situation in the the building! We www.jach.hawaii.edu/JCMT/surveys/ UK has been par-

have been antici- JLS_status.html). ticularly difficult, PRING pating the arrival with the well- of this revolu- Although we are all excited by the documented fi- tionary instru- arrival of SCUBA–2, the reports we nancial difficul- 2008 • #28 ment for so long receive from visiting observers and ties of the STFC now that it is the science results we see from limiting the or- almost difficult HARP/ACSIS are proving that this ganisation’s abil- to believe that it particular instrument combination is ity to make any has finally ar- a powerful one, something which is firm commit- clearly demonstrated by the variety Gary Davis, Director JCMT rived. As we ments. We were Antonio Chrysostomou, write this col- of science reported in this issue. very pleased to Associate Director JCMT umn, a team There are still some minor issues note, however, from the UK ATC is in Hawaii, work- with the instruments which continue that the JCMT was ranked in the top- ing closely with JAC engineering to frustrate us, as is normal with any priority category by the STFC Pro- staff to get the instrument installed new instrument and particularly grammatic Review, making it a and integrated into the observatory those which push the observatory “must-do” project. This is entirely operating environment. The arrival into uncharted territory, but the re- fitting since the JCMT remains the of the instrument has galvanised solve, dedication and ethic of the world’s premier facility for submilli- everyone involved and it is a very JAC engineering, software and sci- metre astronomy: a review of obser- exciting time at the JCMT. ence groups give us confidence that vatory productivity last year by Trim- these problems will eventually be ble & Ceja (Astron. Nachr. 328, SCUBA–2 was delivered with two resolved. 983, 2007) ranked the JCMT first commissioning-grade arrays, one at amongst submm/mm facilities by a 3 each wavelength (450 & 850 μm): Progress with the JCMT Science Ar- very wide margin. they do not meet the science-grade chive (JSA) continues at a steady specification, but they are of suffi- pace. You should all now be Finally, there have been two staffing cient quality for the astronomical downloading your data from our changes since the previous newslet- commissioning of the instrument to archive at the CADC either directly ter which will be of interest to JCMT proceed. A set of science-grade ar- or via your project pages on the observers. First, the JAC reception- rays is scheduled for delivery in late OMP. Gridded cubes have been ist Sharlene Hamamoto resigned in 2008, leading to science operations available for a while, and baselined February to take a position on with the full instrument in early cubes, using a baseline removal pro- O’ahu. This change represents a 2009. We plan to offer SCUBA–2 to cedure developed in-house, will be- good career advancement opportu- the community on a shared-risk ba- gin to roll out in the next few weeks. nity for Shar and we wish her well, sis with the two commissioning- Of course, in the background to this but we will miss her smiling face at D ESK grade arrays in late 2008. there has been a tremendous the front desk and her efficient

amount of technical development maintenance of the vehicle schedule. OF Another important milestone for the and progress on the JSA infrastruc- Second, the JCMT secretary Donna observatory and its community was ture, at both the CADC and JAC DeLorm retired in February after THE reached in winter 2007: the much- sites, which enable and prepare this more than 22 years at the JAC. Us- anticipated commencement of the facility for the next significant stage ers will be familiar with Donna be- D

JCMT Legacy Survey. Three teams of this project: implementation and cause she looked after accommoda- IRECTOR (Spectral Legacy Survey, Gould Belt delivery of Advanced Data Products. tion bookings and a host of other Survey and the Nearby Galaxies Sur- details for visiting observers. We vey) began collecting data for their We have reported previously that all will miss her, both as a friend and as surveys using HARP. In the main, three agencies had indicated their a colleague. At the same time, the data have been of excellent qual- intention to continue operating the though, we welcome the new JCMT ity and some of the early results JCMT for some years beyond 2009, secretary, Linda Gregoire. Linda is have proved to be quite exciting, the year in which the tripartite Canadian by birth but she has lived and we hope to read more from the agreement contains a break point. in Hilo for the past several years and teams on these results within these This remains the case, although the she brings a wealth of experience to pages soon. You can keep up with agencies have not as yet been able the position. Please pop in to say general survey progress on the JLS to commit signatures to paper. The hello on your next visit to the JAC.

Heavy Water in Solar–Type Protostars

Cecilia Ceccarelli (LAOG), Steven Charnley (NASA Ames), & Harold Butner (James Madison)

One of the last few years’ discover- have so far failed to detect deuter- the ground transition of doubly ies is what is now referred as the ated water in the solid state, at an deuterated water (D O), at 316.8 2 “super-deuteration” phenomenon, upper limit of about 2% (e.g., Parise GHz. namely a huge increase of abun- et al. 2003). In the gas phase, Pa- dance of D-bearing compared to H- rise et al. (2005) have measured as After a long integration of about 8 bearing isotopologues in trace mole- little as 3% of HDO with respect to hr, and after verifying the detection cules. This phenomenon is ob- H O in the region where ices are with observations taken at CSO with 2 CIENCE served in regions of low mass star sublimated towards the solar type a lower spectral resolution, we fi- formation, notably in pre-stellar protostar IRAS 16293–2422 (Parise nally detected the line. The ob- cores and in the youngest sources, et al. 2005). When compared to the served line spectrum is reported in the Class 0 sources (see the review abundances of the singly deuterated Figure 1. It shows an emission com- JCMT S JCMT in, e.g., Ceccarelli et al. 2007). So isotopologues of formaldehyde ponent, whose linewidth is 6 km/s, far the most spectacular values have (HDCO) and methanol (CH DCO), and an absorption dip, whose 2 been found in molecules like formal- that constitute more than 1/3 of the linewidth is 0.5 km/s. In the same dehyde (H CO), methanol (CH OH) total molecules’ abundance, the sin- figure we also show the line spec- 2 3 and ammonia (NH ), where the dou- gly deuterated water is a sound fac- trum of the HDO ground transition 3 bly and even triply deuterated isoto- tor ten lower. There may be several at 464 GHz, that was previously ob- pologues have been detected with reasons for this difference of behav- served at JCMT (Parise et al. 2005). abundances of more than 1% ior, including the fact that the abun- Based on the comparison between (Ceccarelli et al. 1998; Parise et al. dance of water may be so large that the two lines and arguments related 2004; van der Tak et al. 2002). it may compete for the main reser- to the radiative transfer of the D O 2 Given that the elemental D/H ratio is voir of the deuterium atoms. line, we concluded that both the D O 2 ~2×10–5 (Lynsky et al. 2005), if the D emission and absorption arise in the and H atoms were distributed statis- One has to emphasize that water is hot corino region, namely the region 4 tically, the abundance of the triply not “just another molecule in the where the ices sublimate because deuterated methanol should be zoo of deuterated molecules”; the the dust temperature reaches 100 K. more than 13 orders of magnitude degree of water deuteration is one The reader can find the full discus- lower than observed! of the claimed hallmarks for the exo- sion of the analysis in Butner et al. genetic origin of the terrestrial 2007. It has been long known that the oceans. For this reason, under- deuteration in molecular clouds is standing the route of water deutera- The detected D O line allows us to 2 due to the reaction of neutral mole- tion is particularly and specifically estimate the D O abundance, found 2 cules with the deuterated molecular important. For this reason we have to be about 1.7×10–10 with respect to ion of H +, H D+, that “transfers” the carried out observations at JCMT of (Heavy Water, continued on page 5) 3 2 D atoms from the main deuterium reservoir, HD, to the trace molecules (e.g., Watson 1976). Only recently it has been recognized that in extreme conditions, the other H + isoto- 3 pologues, HD + and D + also play an 2 3 important, if not a major role in this reaction, giving rise to super- deuteration (Caselli et al. 2003; Roberts et al. 2003; Vastel et al. 2008 • #28 2004). These extreme conditions occur during the coldest phases of solar type star formation, because of PRING three simultaneous circumstances: 1) the low temperature of the gas;

• S 2) the low electronic abundance; and, 3) the freezing-out of the CO molecules onto the grain mantles. Figure 1. — The 1 –1 transition of para-D O at 316.7998 GHz detected in emission and in absorption towards 10 01 2 IRAS 16293–2422 (center). A two-gaussian component fit (green), using the velocity width and V of the HDO LSR Water, however, seems to follow a line is superimposed on the D O spectrum. This HDO line (scaled by ×0.1) is shown at bottom. On top, an emis- 2 sion component is evident in the residual spectra obtained after the D O gaussians have been subtracted, likely EWSLETTER different fate. Observations in the IR 2 due to CH OD. See Butner et al. (2007) for a full discussion. 3

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Evidence of Large–Scale Outflows in the Serpens South Cluster EWSLETTER

Brenda Matthews (NRC/HIA), Robert Gutermuth, Tyler Bourke, Lori Allen (Harvard-Smithsonian), Mike Dunham, Neal Evans, Paul Harvey (Texas), Jennifer Hatchell (Exeter), & Jes Jørgensen (MPI Bonn)

• S

The Serpens South Cluster is a re- seen in extinction. In order to probe For instance, the counterpart to the cently identified region of very ac- the gas content of the region arising strong western blue-shifted lobe is PRING tive, clustered star formation discov- from the filament itself and outflows not seen in the integrated intensity ered by the Spitzer Gould Belt Leg- associated with the YSO population, map in Figure 1. Interestingly, the acy Survey team (see Gutermuth et we have used HARP to map the 12CO 12CO(3–2) emission seems to be en- 2008 • #28 al. 2008, ApJ, 673, 151). Located (3–2) emission from the centre of tirely self-absorbed toward the re- ~3 degrees south of the well-studied the region, and extensive outflows gion with no emission at the sys- “Serpens Main Core” and at a dis- are revealed. The blue-shifted emis- temic velocity of ~9 km/s. More tance of 260±37 pc from the Sun, sion is dominant, delineating several observations to expand the map to the SSC contains at least 91 young collimated outflows to the southwest the southeast and northwest along stellar objects, 59% of which are pro- of the cluster. The red-shifted emis- the filament are in the queue for tostars, with a stellar density higher sion is weaker and more diffuse. semester 08A. than that of the SMC. The mean surface density in the central 2.5 arcmin (0.2 pc) of the cluster is 430 pc–2 with a median projected separa- tion of 3700 AU. Within the Serpens Main Core, the median nearest neighbour distances are much larger 4800 AU, reflecting the fact that the cluster is more diffuse. These con- clusions are based on IRAC data at 3.5, 4.5, 5.8 and 8 μm combined with 2MASS data as published by 5 Gutermuth et al. The IRAC wave- bands are not sensitive to the youngest phase of protostellar evo- lution. Therefore, the surface densi- ties inferred from the Spitzer and 2MASS data are certainly underesti- mates to the total population of the cluster.

In addition to a young population of protostars, the Spitzer images reveal Figure 1. — Spitzer false colour image of some of the filamentary dark cloud structure seen in the Serpens South Cluster. Superimposed are contours of red-shifted and blue-shifted CO emission detected with HARP. North is to an extensive filamentary structure the left; east is down. JCMT S (Heavy Water, continued from page 4) surface chemistry and ion-molecule though we were unable to give a H , and the ratio with respect both reactions both predict D O/HDO ra- definitive answer, the D O detection 2 2 2 H O and HDO: D O/HDO=1.7×10–3 tios ≈4–5 times higher than ob- has helped to rule out some old hy- 2 2 –5

and D O/H O=5×10 . Compare that served. However, in the latter case, potheses and to formulate new pre- CIENCE 2 2 with D CO/H CO=0.1 and CHD OH/ lower D O/HDO ratios are possible if cise ones. 2 2 2 2 CH OH=0.3 in the same source; wa- the gas-phase chemistry of water 3 ter is definitively a peculiar case! and its deuterated isotopologues did References

not attain a chemical steady-state Butner et al. 2007, ApJ 659, L57. In Butner et al. (2007), we carefully prior to most of the molecules con- Caselli et al. 2003, A&A 403, L37. Ceccarelli et al. 1998, A&A 338, L43. examined the possible routes of wa- densing on to dust grains. This sce- Ceccarelli, C., et al., 2007, in Protostars & Planets V. ter formation and tried to under- nario is also consistent with the low Di Francesco et al. 2007, in Protostars & Planets V. Parise, B., et al. 2003, A&A 410, 897. stand if the measured D O abun- fractional abundance of water meas- Parise, B., et al. 2004, A&A, 416, 159. 2 dance can shed some light on this ured in IRAS 16293–2422, and is Parise, B., et al. 2005, A&A, 431, 547. Roberts, H., Herbst, E., Millar, T.J. 2003, ApJ, 591, L41. mystery. We concluded that shock generally consistent with rapid mo- van der Tak, F.F.S. et al. 2002, A&A, 388, L53. chemistry can be ruled out as con- lecular cloud formation and protos- Vastel, C., et al. 2004, ApJ, 606, L127 . Watson, W.D., 1976, Rev. Mod. Phys., 48, 513. tributing to the origin of the water in tellar evolution (Di Francesco et al. this source. At steady-state, grain- 2007; Ceccarelli et al. 2007). Even

Sulfur in the Venus Mesosphere

Brad Sandor, Todd Clancy (Space Science Institute), & Gerald Moriarty–Schieven (JAC/HIA)

The thick cloud layer obscuring Ve- lines allows us to always observe The narrow absorption lines we ob- nus’ surface, and presenting the them simultaneously. In figure 2 serve indicate SO and SO are each 2 planet as a high-albedo, nearly fea- our April 7 (dayside) and August 7 confined above 85 km. Figure 2 tureless cue ball, is primarily com- (nightside) spectra are overplotted. data are well fit by a 2-layer model posed of sulfuric acid (H SO ) aero- The diurnal pattern, stronger SO in which SO abundance is 130±10 2 4 2 sol. For these most famous (and than SO absorption on the dayside, parts per billion (ppbv) at 85–100 2 many lesser known) reasons, atmos- and stronger SO than SO absorption km, and 0.±10 ppbv at 70–85 km. 2 CIENCE pheric sulfur is crucially important to on the nightside is not contradicted The data cannot be fit by a 1-layer Venus, and of great scientific inter- in any of our data. However, there model of SO constant over 70–100 2 est. Its complex behavior involves are observation dates when absorp- km. All our SO and SO absorption 2 gas-phase chemistry, solution chem- tions of both SO and SO are <0.1%, lines are similarly narrow, and can 2 JCMT S JCMT istry (e.g., sulfuric acid dissolves in i.e., neither molecule is detected, only be produced if the absorbing water droplets), phase changes of and no determination of their rela- molecule is confined above 85 km. sulfur (e,g., dry sulfuric acid exists tive absorption strengths is possible. both as a gas, and as a solid aero- (While comparison of SO and SO in This discovery, that SO and SO 2 2 sol), and atmospheric dynamics. absorption units is illustrative, the abundances increase with altitude, SO line is spectroscopically stronger. contradicts all photochemical model Sulfur behavior above the clouds, Mixing ratio of SO is smaller than predictions, and overturns what had above 60 km, was largely unknown that of SO in all our observations.) been conventional wisdom. Chemi- 2 before targeted studies from the cal modeling had predicted SO and 2 JCMT began. Above the clouds and Spectra such as those in figure 2 tell SO would each decrease rapidly with prior to JCMT observations, SO and us mixing ratios of SO and of SO altitude, the opposite of what we 2 SO had been measured at 60–70 increase with altitude. JCMT sensi- observe. Conventional wisdom had 2 km, with IR and UV data that had no tivities to the 70–85 km and 85–100 reasoned that SO and SO are each 2 6 sensitivity to higher altitudes. In km regions are very similar, and alti- rapidly photolyzed by sunlight, and contrast, submm absorption lines tude resolution is derived from pres- should therefore decrease with alti- measured with the JCMT are specifi- sure broadening of submm lines. tude. Observations show that Venus cally sensitive to sulfur at altitudes sulfur behavior is far more compli- 70–100 km. The importance of the cated. The Venus modelling com- earlier 60–70 km IR and UV data munity is struggling to interpret and should not be minimized. However, understand our measurements, submm findings at 70–100 km re- while we plan future observations to veal behaviors unlike anything seen address questions raised by our data below 70 km. Further, JCMT meas- in hand. urements of SO and SO contradict 2 photochemical modeling results that had previously been unquestioned.

Submm studies yielded a first detec- tion of 70–100 km SO in 2004, and 2 subsequent observations are bring- ing many surprises. Sulfur behavior over the entire observed hemisphere is highly variable. On Jan 14, 2007, 2008 • #28 we obtained the first 70–100 km SO detection. Then our Jan 20 meas- urement showed SO abundance had PRING tripled in only six days, and over the entire visible hemisphere (Figure 1).

• S Other observations demonstrate SO 2 abundance also changes rapidly on one-week timescales. Figure 2. — SO/SO absorption spectra toward Venus, 2 taken April 2007 (when Venus was near superior Figure 1. — Sulfur monoxide (SO) absorption spectra conjunction, i.e., showing the daytime hemisphere) and Proximity (130 MHz separation) of toward Venus, taken on 14 January and 20 January August 2007 (near inferior conjunction, i.e., nighttime 2007. Note the 3× increase in absorption of SO in 6 hemisphere). Note that SO appears to dominate the EWSLETTER the strongest B-band SO and SO 2 days! day side, while SO dominates the night side. 2

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Acid Water in Colliding Galaxies EWSLETTER

Floris van der Tak (SRON Groningen)

• S Our Galaxy is currently going study of conditions in the nuclei of in a refereed journal! Although its through a quiet phase of its life, as colliding galaxies, because it is in name may sound exotic to some + do most of the roughly one hundred this waveband where many mole- readers, H O occurs naturally in PRING 3 billion other galaxies in the Uni- cules emit radiation. For example, liquid water on Earth, and its con- verse. But at any given time, a few CO has an emission peak near 345 centration determines the acidity of galaxies go through a restless, ac- GHz and water near 557 GHz. Using the water. Hydronium in gas clouds 2008 • #28 tive phase, where they emit over a submillimetre spectra, astronomers in space emits radiation at submilli- thousand times more light than nor- are thus able to tell the existence of metre wavelengths, most of which is mal galaxies do. The extra radiation certain molecules in clouds at thou- blocked by the atmosphere of the originates in the nuclei of active gal- sands or (with large telescopes) mil- Earth. With special telescopes such axies, which totally outshine the lions of light years from Earth. This as the JCMT, located on a high and galaxies’ outskirts. The origin of information is valuable because the dry site, astronomers are able to this sudden activity is usually a colli- chemical composition of a gas cloud measure this radiation — if the sion between two normal galaxies. contains many clues to the future of weather cooperates. In this case, Such collisions happen quite often in the cloud. The reason is that certain good weather means that the air space, with the Antenna galaxies molecules occur preferentially in contains very little water vapour, and (NGC 4038/NGC 4039) as famous warm clouds, others predominantly therefore: the colder, the better. example. The result of a galactic in clouds at high pressure, and My family always looks funny at me collision may be a burst of star for- again others in the presence of ultra- when I pack a thick sweater in my mation, or the formation of a super- violet radiation. And these basic suitcase for Hawaii! massive black hole (millions of times properties of clouds — temperature, heavier than the Sun). Astronomers pressure and radiation field — deter- The astronomical importance of this observe both these processes in col- mine whether the cloud is stable or discovery lies in the fact that the liding galaxies, but they are not sure will evaporate, or whether it will col- amount of H O+ is a measure of the 3 if they exclude each other or if, for lapse to form stars. total number of charged particles in 7 instance, one precedes the other. a cloud. The more free protons are Since these processes are fundamen- The particles in a gas cloud attract around, the more will bind to an H O 2 tal to the evolution of the universe, each other through gravity, and in molecule. In the two galaxies that I astronomers would like to peer into the absence of other forces, the observed, the number of charged the nuclei of colliding galaxies as cloud will shrink until the particles particles appears to be large enough deeply as possible. In most cases, are so close together that stars that magnetic fields will be able to studying these nuclei is quite hard, form. In galaxies however, large- significantly reduce the rate of star because thick clouds of gas and dust scale magnetic fields occur which formation. Ironically, at least in the block the view like a smoke screen – pervade the gas clouds. The parti- case of M 82, it is the young stars at least to our eyes. But like a pilot cles in the clouds thus feel a mag- themselves that cause the ionization is able to land in fog thanks to ra- netic force which tends to bind them of the gas clouds: the process of dar, astronomers can use long- to the field lines and keeps them star formation is counteracting it- wavelength telescopes (infrared or from falling toward the cloud center. self. In the case of Arp 220 on the radio waves) to look deeper into the The magnetic force only acts on other hand, X-rays from the central JCMT S nuclei of galaxies than in visible charged particles, though. How ef- supermassive black hole seem the light. The submillimetre part of the fectively the magnetic field may most likely origin of the ionization. spectrum is particularly suited to the counteract gravity and prevent the CIENCE formation of new stars thus depends In the next For more information, on how strongly charged the cloud please see A&A, 477, L5 (2008). is. Astronomers thus would like to This work was done in collaboration know the prevalence of charged par- with Susanne Aalto (Onsala) and ticles in gas clouds. Rowin Meijerink (Berkeley).

In April 2007, I have used the HARP instrument, then newly commis- sioned on the JCMT, to discover the H O+ (hydronium) molecule in the 3 Figure 1. — Spectrum of H O+ toward the nucleus of 3 nuclei of two nearby galaxies. This M 82. The spectrum is best fit by two components, a narrow line likely from the eastern molecular peak of is the first result obtained with the M 82, and a broad line coming either from more widely HARP instrument which is published distributed molecular gas, or from the nucleus.

Star Formation at the Edge of the Galaxy

Jan Brand (INAF IRA) & Jan Wouterloot (JAC)

Star formation is very prominent in forming region associated with IRAS Molecular Cloud the inner regions of the Galaxy, es- 06145+145 (WB89–789; Wouterloot pecially at the Galactic Centre and in & Brand 1989, A&AS, 80, 149). This The molecular cloud associated with the molecular ring at galactocentric object is located in the anti-centre the cluster has been extensively ob- distances R≈4–6 kpc. Evidently the direction (l,b = 195.82 deg, –0.57 served in mm-lines and mm- conditions there for the formation of deg). The kinematic distance of its continuum. Most observations were stars from molecular material are associated molecular cloud is 11.9 carried out at the JCMT, although we

CIENCE very favourable. The physical condi- kpc, and it is located at R≈20.2 kpc, also used the IRAM 30-m and the tions of the interstellar medium in at the edge of the (molecular) disk SEST. The JCMT 13CO and C18O J=2–1 the Galaxy change with distance of the Galaxy. and IRAM CS J=2–1, 3–2, 5–4 obser- from the Galactic Centre, and the vations show that the cluster is em- JCMT S JCMT far-outer Galaxy (which we define bedded in a ~500–1500 M (virial  here to be at R≥16 kpc) presents Star Cluster mass) core, of radius 1.1–2.7 pc quite a different environment from (depending on the tracer). This core that in the inner Galaxy. We observed the region around the is contained in a ~5×103 M cloud of  IRAS source with the ESO 2.2-m tele- size 12.6×7.4 pc. These changes might be expected to scope in the NIR (J, H, and K-bands). influence the formation of molecular These observations revealed a com- Molecular Outflow clouds and the star formation proc- pact cluster embedded in the mo- ess within them. Indeed, while the lecular cloud. A false-colour image In the molecular core in which the galactic atomic hydrogen disk has a is shown in Figure 1, left. Analysis star cluster is embedded, an outflow radius of at least 25 kpc, molecular of the star density reveals the pres- is detected. Figure 1, right, shows clouds are found only out to about ence of a cluster consisting of about the integrated 12CO(3–2) emission. 20 kpc. The surface density of the 60 stars, with a radius of 1.3 pc. The total mass of the swept-up ma- molecular disk at that point is only From a [J–H] vs. [H–K] colour–colour terial is <~10 M . An interesting 8  ~10–2 M pc–2 (the H I reaches this  diagram we find at least 14 stars feature in Figure 1, right, is the pres- level at R~50 kpc). The formation of with NIR-excess, indicative of the ence of two extended features near molecular clouds from atomic clouds presence of circumstellar dust and offsets (+10 arcsec, –3 arcsec) and (– at large R is made more difficult by hence of very young objects. Three 16 arcsec, +4 arcsec). These are the continuously decreasing surface of these are possibly Class I objects. brightest in K and virtually absent in density and the increasing scale- The youth of this region is corrobo- J and can be easily recognized as height and the consequent decrease rated by the detection of an H O ma- the red spots in Figure 1, left. This 2 of volume density of the gaseous ser and the non-detection of radio emission might be due to the 2.1 disk. This is exacerbated by a de- continuum emission. μm line of H , a manifestation of the 2 crease in metal abundance and dust (Star Formation, continued on page 9) by a factor of 10, hence by a de- crease of H formation sites. 2

Nevertheless star formation is occur- ring out to large distances from the Galactic Centre. Star formation indi- cators such as the detection rate of water masers, the number of H II regions per unit mass of H , and the 2 2008 • #28 number of bright FIR sources per H II region indicate that once mo- lecular clouds are formed, there is PRING no difference between star-forming activity near the Sun or in the

• S Perseus arm and in the outer Galaxy.

Figure 1. — (left) False colour image (J=blue, H=green, K=red) of a ~1.7 arcmin × ~1.7 arcmin region around As part of our long-term study of WB89–789. (right) Map of the integrated 12CO(3–2) wing emission (JCMT-data). Blue (drawn): 20

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SCUBA Data on Google Earth EWSLETTER

Robert Simpson (Cardiff)

• S Google Earth is a free and cross- of this issue). You can see the line you’ll first need to have the latest platform software package which where the purple, optical image bor- version of Google Earth installed. enables users to fly around a 3D ders the normally invisible, orange Then download the XML file from PRING Earth, patchworked together from 850 μm data. the SCUBA Legacy page at CADC. All satellite and aerial photography. links are given below. The file Last Summer, Google announced The extended SCUBA point source should open and then take a mo- 2008 • #28 that Google Earth could now also catalogue is also included and these ment to download some data before become Google Sky (Scranton et al. appear as green hexagons in the it begins. 2007). In a similar fashion, users images here. This list provides for can explore the interior of a virtual each object, in both 850 μm and The data layer should also appear celestial sphere. Google Sky is not 450μm bands where available, the soon in Google’s own catalogue to made up of aerial photos, but of respective maximum intensity, esti- maximise exposure to the public various star catalogues and sky sur- mates of total flux and size, and and to Google Sky users in general. veys that are publicly available, e.g., tentative identifications from the the DSS and many Hubble images. SIMBAD Database. I have also added SCUBA Legacy Catalogues can be a short list of ‘interesting’ features downloaded at http:// In an effort to engage the public in for those not familiar with SCUBA. www.cadc.hia.nrc.gc.ca/community/ submillimetre astronomy, I have scubalegacy/; Google Earth at http:// made the SCUBA emission maps and Google Sky reads an open XML file earth.google.com/. the point source catalogue available format that allows anyone to create References on Google Sky in what is called a compatible data for display. Here layer. The data are hosted by the the SCUBA catalogue FITS images “The SCUBA Legacy Catalogue: Continuum Objects Detected by SCUBA”, James Di Francesco, Doug Johns- CADC, who also host the complete have been converted into a format tone, Helen Kirk, Todd MacKenzie, Elizabeth Ledwosin- public SCUBA catalogue of maps Google Sky can read and the rele- ska, 2007 (astro–ph/0801.2595). upon which this Google Sky layer is vant XML has been generated. The “Sky in Google Earth: The Next Frontier in Astronomi- 9 based (Di Francesco et al. 2007). It maps are designed to download to cal Data Discovery and Visualization” ,Ryan Scranton, Andrew Connolly, Simon Krughoff, Jeremy Brewer, is now possible for anyone to access the user dynamically, saving Alberto Conti, Carol Christian, Brian McLean, Craig the SCUBA maps through Google download time and disk space. Sosin, Greg Coombe, Paul Heckbert, 2007 (astro– Sky, simply by downloading the To access the layer in Google Sky, ph/0709.0752). small ‘layer’ file.

Viewing the 850 and 450 μm contin- uum data on Google Sky means that anyone can begin to visualise what the submillimetre universe looks like in relation to other wavelengths and objects. The easy-to-use zoom and pan tools allow anyone to get a feel JCMT O for the size and scope of the data available. An example is shown here in a screen capture from the applica- Figure 1. — Google Sky offers SCUBA point sources Figure 2. — Click on a green hexagon in this 850 μm and images as a complement to its optical images. image (of the HH 783 neighbourhood of the B1 molecu- tion showing the Horsehead Nebula PERATIONS Here we see the Horsehead Nebula optical image lar cloud) in Google Sky, and a popup appears with the in both visual (Figure 1) and submm (purple) with the SCUBA 850 μm image in orange. The name and submm properties of the selected source. (Figure 2) bands (also see rear cover green hexagons are SCUBA point sources. (Also see (Also see rear cover of this issue.) rear cover of this issue.)

(Star Formation, continued from page 8) uncertain because the radial velocity type of K3 III. The distance of this interaction between the outflow and is not very sensitive to the distance, star would then be 10.7 kpc (R≈19 the ambient medium. and random motions become rela- kpc), consistent with the kinematic tively influential. In fact, a cloud- distance and confirming that this is Distance cloud velocity dispersion of ~5 km/s truly a star cluster at the very edge could allow a range in galactocentric of the Galaxy. This embedded star cluster is lo- distance of WB89–789 of 17–25 kpc. cated near the galactic anti-centre However, a spectrum taken of one of More details can be found in Brand & direction, where the determination the members of the cluster indicates Wouterloot 2007, A&A, 464, 909. of kinematic distances is notoriously an (admittedly uncertain) spectral

The Abundance Profile of CO in Neptune’s Atmosphere

Brigette Hesman (NRAO), Gary Davis (JAC), Henry Matthews (NRC/HIA), & Glenn Orton (NASA JPL)

Using the JCMT and the CSO, carbon from the stratosphere and tropo- here. monoxide (CO) was discovered in sphere respectively. The heterodyne the stratosphere of Neptune through receiver B3 at the JCMT was used to Observations of the CO J=3–2 transi- the detection of the J=3–2 and 2–1 perform this technique; the results tion in Neptune were carried out on rotational transitions in emission at of these observations are reported (Neptune, continued on page 11) 345.8 and 230.5 GHz respectively (Marten et al. 1993). This discovery

CIENCE was unexpected because CO is not thermochemically stable at observ- able levels; it was conventionally thought that Neptune’s atmospheric JCMT S JCMT carbon must be in its reduced form of methane (CH ). 4

Two explanations have been pro- posed for the presence of CO in Neptune’s stratosphere. The first consists of CO being transported from the interior to higher altitudes by convection due to Neptune’s strong internal heat source. If this were the only mechanism, then ther- mochemical models require the inte- rior to be enriched in oxygen by 440 10 times over the solar abundance in order to produce the observed stratospheric CO abundance (Lodders & Fegley 1994), and indi- cate a planetary interior composed Figure 1. — The antenna temperature spectra of Neptune, measured using receiver B3 at the JCMT. Resolution, primarily of water ice. The second 1.25 MHz; band overlap, 70 MHz; bandwidth, 920 MHz. Each of the 25 tunings is indicated by a different color. hypothesis involves the external The grey curve shows a smoothed version of the data. supply of OH radicals or oxygen at- oms into the atmosphere where they can be combined with by-products of methane photochemistry to pro- duce CO (Rosenqvist et al. 1992). It is unlikely however that an external supply of oxygen can be the domi- nant source of CO in Neptune, con- sidering that Saturn has more abun- dant water sources (rings, satellites) but a much smaller stratospheric CO abundance (<10–7 compared to 10–6) (Noll et al. 1986). 2008 • #28 In order to determine the correct mechanism, a measurement of the PRING CO abundance profile through the atmosphere is required. This is best

• S accomplished by high spectral reso- lution measurements that cover a large bandwidth so that a single ob- servational technique can resolve the narrow emission core and the Figure 2. — The model temperature profile (dashed curve) and the CO profile (black) required to produce the best-fit model to the data in Figure 1. The red line indicates the division between the stratosphere and tropo- EWSLETTER broad absorption line that result sphere regions.

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Starlink Software Collection: Humu Release EWSLETTER

Brad Cavanagh (JAC Software Group)

• S Since the last Newsletter, the Joint Automated file provenance tracking The humu release includes many Astronomy Centre has made another allows one to track input files more improvements and bug fixes. release of the Starlink Software Col- through the entire history of any file As always, information about the PRING lection. Named “humu” (Hawaiian for processed with the Starlink software. Starlink Software Collection can be Altair), this release includes major New KAPPA applications PROVADD found at http:// 2008 • #28 improvements to 3-D visualization. and PROVSHOW allow you to add to starlink.jach.hawaii.edu/. GAIA can now volume render cubes, and view provenance history, respec- as shown in Figure 1. This figure tively. shows an iso-surface rendering of a CO map of M 51 (courtesy Remo Tilanus). There are myriad other im- provements to GAIA, including being able to examine two cubes and slices through those cubes simulta- neously, overlaying more than one cube in the 3-D visualization window for comparison purposes, and more command-line options for better programmatic control.

The humu release also includes a new KAPPA application called PLUCK, which can be used to extract data from interpolated WCS co-ordinates that may not correspond to a pixel 11 centre. For example, with PLUCK you are able to extract a spectrum from any given equatorial co-ordinates from a spectral cube. Figure 1. — Gaia 3-D visualization: Iso-surface volume cube rendering of an M 51 CO map. (Image courtesy Remo Tilanus/JAC.)

(Neptune, continued from page 10) to avoid post-processing baseline in the upper stratosphere (Figure 2). a series of dates in 2003 and 2004. adjustments which would severely The stratospheric emission core is limit the accuracy of the data set. The measured CO abundance profile easily measured due to the high Fortunately, the instrument calibra- indicates the presence of both an resolution achievable by heterodyne tion stability was such that the data internal source, which provides the receivers. The tropospheric absorp- quality was excellent and no such tropospheric and lower stratospheric

tion feature, however, is strongly adjustments were required. The CO, and an external source which JCMT O pressure-broadened and covers a observations ultimately covered a provides additional CO to the upper large frequency range (~20 GHz). frequency range of approximately atmosphere. It is postulated that This makes it significantly more dif- 20 GHz around the central frequency the external source could be due to ficult to measure with traditional of the line. a cometary impactor in Neptune’s PERATIONS heterodyne techniques. The line past since meteorites and planetary was therefore measured in 25 dis- A Neptune atmospheric model, de- grains cannot completely account crete segments with tunings spaced veloped for this project, was fit to for the additional CO in the upper by 850 MHz, a resolution of 1.25 the measured spectrum to deter- atmosphere.

MHz, and a frequency overlap at mine Neptune’s CO profile. A best- each tuning of approximately 8%. fit CO profile was determined For further details, see Hessman et The overlap between tunings was through a least-squares fit in which al. (2007). necessary to provide an indication of the tropospheric abundance, strato- baseline continuity. spheric abundance, and pressure References

level of the transition layer were in- Hesman, B. E. et al. 2007, Icarus, 186, 342. The measured CO feature is shown dependently adjusted. The best-fit Lodders, K. & Fegley, B. 1994, Icarus, 112, 368. Marten, A., et al. 1993, ApJ, 406, 285. –6 in Figure 1, with the tuning bands abundances are 0.6×10 in the tro- Noll, K. S. et al. 1986, ApJ, 309, L91. indicated by different colors. Base- posphere and lower stratosphere, Rosenqvist, J. et al. 2002, ApJ, 392, L99. line continuity was crucial in order increasing with altitude to 2.2×10–6

Pointing the Way: The JCMT Pointing Project

Iain Coulson (JCMT Support Scientist)

Introduction However, JCMT is able to point rea- point-like and bright! — before per- sonably accurately, by which I mean forming the intended observation? JCMT has produced superb submilli- “with a random error of about a cou- Why the need to point on something metre astronomy over the past ple of arc-seconds”. I shall try, in near the target, something local!? twenty years, some of which is high- this short article, to explain some The (potential) problem is that sys- lighted in this and earlier issues of aspects of JCMT pointing that may tematic pointing errors may prevent the JCMT Newsletter. It has revolu- comfort anyone wondering if they’re the useful transference of pointing tionized our view of the Universe sitting on a goldmine of exciting corrections derived in one part of PERATIONS near and far with detections of dis- JCMT data, or on a big pile of boron the sky to observations made in an- tant, dusty galaxies, images of monosulfide. other. This will be the case if the nearby, dusty, debris disks, and structural imperfections of the tele- spectra of galaxies, clouds, stars Submillimetre Pointing Sources scope are poorly understood, i.e., if JCMT O JCMT and various solar system bodies the telescope model is poorly deter- taken at molecular transitions too The JCMT pointing catalog is in two mined. numerous to mention. On their general parts; sources that emit own, and presented without regard submillimetre continuum radiation, These imperfections are ab initio to strict precision, such data might and those that emit line radiation, unknown to the precision necessary. still have the ability to amaze. But principally the J=2–1 and J=3–2 tran- If the telescope rotated symmetri- making scientific sense of such data, sitions of CO. The former category cally about a perfectly vertical axis, often by comparison with other data comprises mainly blazars, the latter on a smooth, flat surface, and was taken at other telescopes, requires, mainly stars of various types; some constructed of totally inflexible at a minimum, that it be known from compact Galactic H II-regions or dark struts, then its direction of pointing where the data come. What position clouds fall into both categories. could be simply(!) read from some on the sky, or what part of the ob- Objects of all types qualify for our fiducial marks, or, in practice, from 12 ject in question was observed? If catalog on the basis of their bright- encoders. But, in reality, such is not you can’t assign a specific location ness and compactness. In the days the case. The antenna rolls on a to your data they may be as good as of SCUBA a minimum of ~1 Jy was lumpy, bumpy track, its main useless! It’s the business of the needed to permit continuum point- (azimuth) axis is not vertical, and its Pointing Project at JCMT to ensure ing to take less than a few minutes elevation axis is not perpendicular that such assignments are as accu- of precious observing time, while for to the azimuth axis — to list only rate as possible. our suite of heterodyne spectral line the principal defects. The imperfec- detectors, integrated line strengths tions are small by engineering stan- In the era of space telescopes we are of a few Kelvin km/s are needed to dards (the azimuth axis deviates accustomed to spatial resolutions of facilitate equally rapid ‘spectral line’ from the vertical by only about 15 sub-arcsecond dimensions, and in pointing. Objects that meet these arcsec), but they are big enough to that regard JCMT may seem to have conditions, however, are astonish- have dire consequences for a tele- relatively poor capabilities. Its re- ingly rare: only about 30 blazars are scope with a beam of just that size. solving ability (its ‘beamsize’) is lim- brighter than 1 Jy at 850 μm, and The track model and the 7- ited by its physical dimensions (15 the number of suitably bright spec- parameter (telescope) pointing m diameter primary) to about 15 tral line pointing sources is not model attempt to quantify these im- arcsec at 345 GHz (850 μm). And much larger. On average that’s only perfections so that the encoder read- whereas in the optical or infrared one or two of each type in each 10 ings can be suitably corrected to there will be stars near each astro- deg2 patch of sky! As a result, the yield the direction of pointing. nomical target to which the science catalog also holds some bright 2008 • #28 data can be referenced for positional sources that are not entirely point- The three-parameter track model is accuracy, the submillimetre sky is like: they allow rapid pointing, but measured using tiltmeters at three poorly populated by bright, point- with consequent potential loss of locations on the antenna, and is im- PRING like objects. We certainly have no precision. When observing in some plemented as a lookup table of cor- chance of auto-guiding on a bright parts of the sky the observer faces rections. The telescope model is

• S (submm) source in the field. Point- uncomfortable compromises. derived from all-sky pointing obser- ing with JCMT — something that vations of sources around the sky ought to be a routine part of observ- The Telescope Pointing Model and the optimization of a fit to those ing — can be frustratingly time- observations implemented as a soft- consuming. So why not just point on something ware package called TPOINT. The

EWSLETTER point-like and bright — anything (Pointing, continued on page 13)

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(Pointing, continued from page 12) EWSLETTER TPOINT model comprises geometri- Data Processing Au Revoir cal expressions of the effect of each Developments known structural defect upon point- Jonathan Kemp (Editor, JCMT/UKIRT ing in both azimuth and elevation; the unknown quantity being the am- Telescope System Specialist) • S The JCMT continues to improve and plitudes (coefficients) of those ef- augment its data processing capa- fects in each case. After the point-

bilities. A web log of reduction pipe- PRING ing data are fit, and the model coef- After more than a decade at the Joint line and archive product activity and ficients derived, the resulting rms Astronomy Centre, as the editor of progress can be found at http:// and main force behind the JCMT

scatters of the corrected data reflect 2008 • #28 . the accuracy of the model. The pipelinesandarchives.blogspot.com/ Newsletter for the past eight years, nominal performance of JCMT is and as my collaborator on the most characterized by rms scatters on the The optical paths from each receiver recent editions of the JCMT Newslet- sky in (azimuth, elevation) of (1.5 to the sky are not coincident and so ter these past few years, Gerald will arcsec, 1.5 arcsec). each receiver needs a pair of be leaving JAC this summer to take (azimuth,elevation) collimation con- up a position with NRC at HIA in Vic- The multi-parameter nature of the stants added to the basic (RxA-) toria. Gerald’s tireless Newsletter model (and the underlying structural pointing model. With some instru- leadership, dedication, and contribu- knowledge) allows for any system- ments in the Cassegrain cabin (RxA) tions will certainly be missed. But atic trend in the distribution of er- and others at Nasmyth (HARP and we’ll always keep a few column rors to be identified with a particular SCUBA–2) it is also possible that inches warm for you. Aloha! defect, and then corrected appropri- other model terms as yet unex- ately. (TPOINT also allows for the plored (e.g., cabin flexure) may be couple of weeks, and load adjust- correction of other (empirical, un- needed for complete modelling of ments on the central bearing every physical) trends, should there seem the pointing of all receivers, al- semester or so — earthquakes pose to be any). The residuals thereafter though there is no evidence (no un- particularly urgent challenges to the should then be normally distributed. predictable systematic trends) for maintenance of pointing accuracy. If this were not the case, pointing in such terms at this time. Dedicated pointing runs one direction and observing in an- (redeterminations of the pointing other — the scenario that started Pointing in the elevation direction is model) have not been warranted for 13 this section — would impose sys- also found to be a function of the many months, but vigilance is re- tematic pointing errors on the sci- temperature of the antenna; specifi- quired if new or changing systemat- ence observation. Cautious observ- cally the temperature difference be- ics are to be detected early. ers will wish to minimize any and all tween the front and back legs. such potential systematic effects When the front legs are warmer than All of us at JCMT eagerly await the and will “point-up” as locally as pos- the back legs, as happens when the arrival of SCUBA–2. From a pointing sible. carousel doors are open during the perspective, it should open up new day, the front legs expand differen- avenues in improving the pointing Collimations and Other Terms tially, and the antenna may be imag- performance of the telescope since ined to rock back onto its back its superior sensitivity will allow de- Since SCUBA was retired in 2005, we wheels. The dish is then pointed too tection of many of the fainter have adopted the single-detector high in the sky. The amount of the blazars currently populating the JCMT O 230 GHz Receiver A as our primary error has been both estimated (FEA) catalog, and which have, to date, pointing instrument, and perform- and observed at ~6 arcsec/deg C. never been used. All-sky pointing ance statistics have not changed may actually live up to its name! much from the nominal (SCUBA) fig- The Future With instrument-to-instrument colli- PERATIONS ures above. By comparison with mations determined on the brighter RxA, the pointing of the 16-receptor We have measured the structural targets we should be able to transfer B-band array, HARP, is complicated misalignments, the track profile, and what we hope will be the superior by its field rotator (the K-mirror) thermal characteristics — many, quality pointing accuracy of SCUBA– which lies between the tertiary mir- many times! Algorithms in the tele- 2 to all our detectors. ror (the receiver cabin) and HARP (at scope control software make correc- right Nasmyth). The K-mirror has its tions for track irregularities, antenna The (1.5 arcsec, 1.5 arcsec) rms bar- own misalignments, which are small, temperature, receiver collimations rier is just waiting to be broken. but which have proven somewhat and so on — and these work fine — elusive to determine. That particular but we cannot rest on these laurels. Further details of the activities sum- project is in progress, but data so While the foundations of JCMT are marized here may be found at the far (Feb 2008) suggest fitted rms subject to (slow) subsidence — thus JCMT pointing homepage (http:// scatters of ~2 arcsec in each coordi- prompting routine inclinometry www.jach.hawaii.edu/JCMT/telescope/ nate should be possible. (track profile measurements) every pointing/).

The Night Shift

Jim Hoge (JCMT Telescope System Specialist)

Each newsletter, a Telescope Sys- All observers are familiar with the short, without ETS you would have tems Specialist (TSS) is bullied into excellent job done by our support to rent a vehicle or take a cab just to writing a short article concerning scientists and TSS but most do not get to H.P. JCMT Operations. After ducking this see the work done behind the responsibility for years, I have been scenes to ensure their Mauna Kea Traveling from H.P. to the summit, caught. I spent many of my forma- experience is a satisfactory one. things become even more interest- tive years in the “Silent Service” and Visiting observers are exposed to ing. Now you have to worry about find that I am better at keeping se- most of the JAC organization. They road quality, studded tires, vehicles PERATIONS crets than I am at telling tales. talk to Admin regarding hotel and that are capable of negotiating the Please forgive my lack of eloquence Hale Pohaku reservations. They in- dirt roads and unfriendly environ- and simply accept this article as a teract with the Friend of Project ment above 3,000 m. ETS maintains brief testament to some of those while developing their observing our 4 wheel drive trucks. Along with JCMT O JCMT who are really responsible for the plan (MSBs). Observers are briefed brakes, transmission, fluids, etc., successful operation of the world’s and supported by one of our sup- they ensure that snow chains, emer- best (my opinion but shared by port scientists. Others within the gency equipment, satellite phones, many) submillimetre telescope. JAC organization are also involved and other equipment are available but perhaps indirectly. Without our and in good condition. I have been a TSS for JCMT nearly contingent of software and network eight years. During that time we engineers, the telescope will not run Snow crew: When you arrive at have retired two receivers (three if at all. This group works in the back- JCMT, you might not even be able to you count the “C” band of RxW) and ground but observers are indirectly get into the building without ETS. three backend processors. We have exposed to them every time we have Snow can fall on Mauna Kea from added two new receivers, commis- computer or network issues while October through June. Conditions sioned a much more capable observing. All of these people are can get bad at any time of the year. 14 backend processor, completely re- incredibly important and critical to We have a snow clearing crew that is vised all telescope control system accomplishing your mission. on call and will respond rapidly to software, installed a new network, bad weather conditions. Clearing added interfaces and controls that The Visiting Observer’s exposure to JCMT is not an easy task with its allow us to become part of a larger ETS is much different; before our large flat roof, huge doors and interferometry array, added thou- heavy engineering SCUBA–2 facilities frame structure. In severe weather it sands of square feet of equipment upgrade period which started in Feb- can take days to return the facility to spaces, hosted at least six visiting ruary 2006, our observing night was full service (think about working in receivers, upgraded our engineering 16 hours on the sky and visiting sci- sub zero temperatures at 4000+ m consoles and secondary mirror elec- entists would at least see and meet elevation with high wind, intense tronics, modified our support equip- some of our ETS personnel at the sun, etc.). When winter hits Mauna ment, rebuilt/reinforced the tele- beginning or end of shift. Since re- Kea, without ETS, you are limited to scope and carousel for SCUBA–2, opening the facility in September watching movies and playing pool at and in general have done whatever 2006 we have been doing 12 hr H.P. necessary to ensure that JCMT re- shifts and the people that keep JCMT mains a world class facility. Having operating are seldom seen. This Inside the building: The JCMT Facil- said all that, I can honestly say that dedicated (and surprisingly small) ity, although not as complex as a my own part in all this change was group goes to work when the ob- nuclear submarine, has an impres- insignificant. [Editors’ note: NOT!] servers and TSS are going to sleep. sive array of advanced (complex) TSS are trained to operate and do If this were a VERIZON commercial, I systems including telescope and 2008 • #28 limited journey repairs. The scope would be talking about the carousel drive systems, roof and of the work accomplished far ex- “network”. This is the group that door electronics and pneumatics, ceeds my limited talents. That is keeps our ship afloat. cryogenic compressors, chillers, air PRING why I would like to spend a few mo- compressors, electrical distribution ments talking about one of the Observer Interactions with ETS systems, the star lift, overhead

• S groups responsible for the miracu- cranes, etc. ETS works on every lous transformation and which con- Getting there: Our ETS group per- system. tinues to improve our facility: ETS forms vehicle maintenance on our or Engineering and Technical Ser- sedans, changes out tires, ensures Looking up: After the roof and vices Group. the brakes work and that the trans- doors are opened and the telescope

EWSLETTER mission will keep you moving. In (The Night Shift, continued on page 15)

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(The Night Shift, continued from page 14) EWSLETTER has slewed to a source, you want to The Last Word use HARP (or RxA3i or RxW or SCUBA–2). ETS maintains our receiv- Gerald Schieven (Editor, JCMT Support Scientist) ers as well as our back ends (ACSIS).

These are complex, unique (one-of- • S a-kind) pieces of equipment operat- This issue marks my final effort at editor/co-editor, and the third which ing in the most unfriendly of places (co-)editing this Newsletter, as I will is to be printed glossy-magazine- and operating at temperatures be leaving in July after nearly 13 style. If you’re wondering why PRING where even our normal understand- years at the JAC. These years have you’ve not seen any of the previous seen many major changes here at issues lying on coffee tables, we’ve

ing of physics and electronics is 2008 • #28 challenged. Think Josephson effect, the JCMT. When I arrived, the only unfortunately had some “issues” indium seals and bolometric arrays. continuum instrument was (the al- with the printer. The first printing Consider the skilled people required ready-venerable) UKT14, our B-band came back with some glaring prob- to make these instruments work. receiver was still single-pixel, single lems, which took much time sorting Although we receive technical sup- polarization, and double sideband, out. The second issue was put out port for our newest equipment, the and higher frequencies were ob- for bid after sorting out the first is- support personnel are thousands of served with RxG. There was no Ob- sue, and should be delivered to us kilometers away and our own ETS servation Management Project soon. Both issues will then be sent group does the actual work. (OMP). SCUBA was delivered about a out together. Now that we have a year later, and the following year printing company, the current issue Operational Support: This same began operations just in time to should be ready to mail out much group provides 24 hour support to make phenomenal use of an ex- more quickly (we hope!). us while we are operating. Our ETS tremely dry El Niño over the winter personnel are so knowledgeable that of 1997–98, with week after week of Editing the Newsletter has been one they can lead a TSS to the correct grade 1 weather. More than any of the highlights of my tenure here action over the telephone in many other, that instrument made the at the JAC, and working with Jona- instances. In nearly eight years of JCMT, and quite literally revolution- than Kemp (my co-editor for the past operation, I do not remember a sin- ized astronomy with its discoveries. four issues) has been very reward- gle instance in which ETS was unable It was indeed a heady and exciting ing. I’m not sure who will be co- to bring the facility back to life after time. That heady atmosphere prom- editing with Jonathan, but if you 15 a casualty. Most times the problems ises to repeat itself now that SCUBA– have an idea for an article for the were corrected between the end of 2 has been delivered. next (fall 2008) Newsletter, please one night shift and the beginning of send it to him at th the next. This issue also marks my 12 as [email protected].

As an example, a full year before spectral capability. port and install SCUBA–2 and ACSIS. ACSIS (our new spectral back end) Without their support, there proba- was received, our old backend (DAS) Another example, while observing bly wouldn’t be a SCUBA–2. was nearly destroyed by a winter ice on New Years Eve, our secondary and rain storm. Water got into the mirror stopped operating. We were In short, ETS deserves a lot more facility and pooled on the roof of the unable to adjust the z axis rendering than one page. I had the great control room. This water then trav- the telescope unusable. At 8:00 am pleasure of working with ETS during eled along conduit and wire trays New Years day, I contacted ETS. By our infrastructure upgrade and I JCMT O into the DAS where high speed fans, 11:00 am two of our technicians consider them to be the heart and used to cool the electronics, blew were at JCMT working on the prob- soul of our facility. Keep in mind, the water all over much of the sensi- lem. By 5:30pm, the SMU was re- this group maintains both UKIRT and tive electronics. After initial damage paired and we had an excellent night JCMT. PERATIONS control to stop the water from get- of Grade 1 observing. ting into the DAS, our electronics One final note, working at JCMT has technicians almost completely disas- The future: ETS does much more been exciting and fun. With the arri- sembled this complex piece of than just maintain the facility and all val of SCUBA–2 our lives will become equipment. Circuit boards were of its equipment. When the cost even more interesting and I see dripping water, and corrosion associated with SCUBA–2 appeared nothing but good things in the fu- started as soon as the water came in to be prohibitive, ETS agreed to do ture of JCMT. If management only contact with these boards. For a full facility modifications and upgrades asks me to write an article every 5 year, ETS had to continually clean along with their normal jobs, to try years (or so) then I have only two or and combat corrosion within the and save the JAC money that could three more articles to go before system. They kept the DAS operat- be used for development. Our ma- SCUBA–2 and I both retire. I suspect ing until it could be replaced. With- chinists and welders made the mas- I can manage that. out the DAS we would have had no sive modifications required to sup-

Observatory Pointing Model Developments New Starlink Software Collection Release

SCUBA Data continuum data now integrated with Google Earth

www.jach.hawaii.edu/JCMT jk