In-Person Observing Run at CTIO

2 minute read


I finally got a chance to do some in-person observing run, and what a better place to do so than the DECam at the 4-M Blanco Telescope at the Cerro Tololo Inter-American Observatory (CTIO)!

This is my third time in Chile and also third time back at CTIO. When I first arrived here as a REU intern way back in 2015, DECam was the biggest deal in town. This half a gigapixel camera with 3 square degree field of view is optimal for imaging large swaths of the sky and for extragalactic analyses. While at that time I only got to use the 0.9-M SMARTS telescope for one night, I always wanted to try my hands on DECam someday. So when the opportunity arose to do some in-person observing, I said yes!

Goal of the Observing Run

As you may know from my research page already, the Dark Energy Spectroscopic Instrument (DESI) is making the largest 3D map of the Universe in spectroscopy. However, to know a priori which targets we should get spectra of, we need good quality imaging data for target selection. Since DESI is way ahead of its schedule, the collaboration has decided to extend some further imaging as a part of the DESI Legacy Imaging Surveys and get a better completeness of the Southern sky.

This resulted in the collaboration at-large winning nights at CTIO, and I will be involved in observing for 5 nights, in g-, r-, and z-bands.

Day 0

I took a 10.5 hour long direct flight from JFK to Santiago and then another 1 hour flight from Santiago to La Serena, followed immediately by a 2 hour drive to the CTIO mountain top. It was as exhausting as it sounds but the delicious food of CTIO always is there to make your day!

My co-observer and I decided to shadow the Observing Support for this night and got rewarded with some breathtaking views of the Milky Way and the Magellanic Clouds.

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Day 1

We received some great in-person advice and support from the Science and Observing Support team here today. Once I figured out the controls, I got busy with the fancy control setup!

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Sadly, the entire night was pretty much a bust because of unuusal cloud coverage. Fingers crossed for tomorrow!