Surveying the Southern Sky with a Robotic Camera John E. Gaustad Swarthmore College Wayne Rosing Las Cumbres Observatory

SHASSA Southern H-Alpha Sky Survey Atlas

Survey Properties Coverage: declination +15 to -90 Image size: 13 x 13 degrees Image resolution: 0.8 arcminutes Images to cover the sky: 283 Sensitivity: 2 rayleigh (50X better than POSS) Purpose: –study structure of ISM –set limits on free-free contribution to microwave foreground

We difference line and continuum images:

Equipment 50 mm f/1.6 Canon lens Spectrasource CCD camera, TE cooled 1024x1024 TI chip, 12 micron pixels Filters: 3 nm H- , 6 nm dual-band cont. Byers German mount 10-foot dome from Technical Innovations Two PCs, Win95, Visual Basic & IDL

Location: Cerro Tololo (Chile)

Lessons Learned

It Will Take Longer Than You Think Dec ’92DVB “We ought to do a survey.” ’93-’96Pilot study Apr ’96Pilot study paper published Jul ’94 First NSF proposal rejected Jul ’95 JG met WR at Pittsburg AAS May ’96Second NSF proposal funded Nov ’97First observations at CTIO Oct ’00Observations completed Nov’01Survey published in PASP

Robotic is Good Robots don’t need much space –But the people who set them up do – plan plenty of space for people to move around while installing and repairing Robots don’t get bored Robots don’t have to be paid – relatively cheap project

SHASSA Project Cost Las Cumbres Obs.40,000 Dudley Observatory10,000 Fund for Astr. Res. 5,000 AAS 3,000 Keck NE Ast. Cons.15,000 Swarthmore College 27,000 NSF ,000 NSF ,000 NASA-JPL15,000 TOTAL $217,000 Wisconsin H-Alpha Mapper 2 million Two-micron All Sky Survey 20 million Sloan Digital Sky Survey 100 million Microwave Anisotropy Probe 180 million SHASSA0.2 million = 1 deci-wham = 1 centi-2mass = 2 milli-sloan = 1 milli-map

Humans Are Useful A truly unattended instrument is costly Location at an established facility gives –easy access during setup and testing –logistic support, power, network access, etc. –local staff able to make minor repairs, reboot computers, etc. –human judgments on weather and safety (communicated by to the robot) –camaraderie with other scientists

Perfection is Unattainable There is no such thing as an uninterruptible power supply Computers do fail: –add cooling fans to power supplies and CPUs –record data redundantly on separate disks Learn when to say “this is good enough” – rely on humans for the rest

Keep It Simple Use a simple shelter, such as a roll-off roof, not a dome Use separate computers for telescope control, camera control, and communications, so these tasks don’t interfere with each other Use a computer system compatible with the local network Invest in accurate telescope drives, so guiding and focusing is not an issue

Test, Test, Test Pre-deploy a trial computer at the remote site for a few months, in order to identify power supply, network reliability, and communications problems Integrate and operate the ENTIRE system at home before deploying to a remote site Allocate a month or more for initial installation and testing at the remote site

Do a Pilot Study Helps to clarify scientific goals Identifies technical problems If it ends up with publishable results, establishes credibility with funding agencies

Benefits of Amateur- Professional Collaboration

Point of View of Amateur Professionals provided –knowledge of scientific goals –credibility with funding agencies, observatory directors, journal editors –project management –data reduction skills –experience in writing scientific papers

Point of View of Professional Amateur provided –high-quality instrumentation –technical expertise –engineering time –enthusiasm, confidence, and dedication This meant the project could be done at much lower cost to funding agencies than would otherwise be possible.

Would We Do It Again? Yes! But with more realistic expectations of time and effort involved. In fact, we are now repeating the survey at the wavelengths of [SII] and [OIII] lines