Observing at the Cerro Tololo Inter-American Observatory and 5 reasons why it is awesome


Today is a big day for me. It will be the first time I get to observe at a working research observatory! I have been teaching Astronomy Lab to 2nd year undergrads for 3 years now, and prior to that I was the telescope officer during my undergraduate studies. All of this has been preparing me for this moment. Excited is an understatement.

The Cerro Tololo facility (CTIO) is one of the few observatories that lie south of the equator in Chile. This is great to look at things in the Southern Hemisphere, such as my galaxy clusters! The location is dry and low light pollution, perfect for observing.
At an altitude of 2,200m, the pressure here is 79kpa and only 78% of oxygen would be available to us compared to if we were at sea level. Usually astronomers will go up the mountain a day or so before observing, to acclimatise to the altitude and prevent them from being sick.

Here are 5 things that I think make CTIO one of the coolest observatories in the world:

1. The main telescope on CTIO is the 4m Victor M. Blanco. It was built in 1974 but is still actively working today!

2. When CTIO was first built the road infrastructure wasn’t the best. It would take 3 hour drive from La Serena to Vicuña, 6 hours horseback ride to Los Placeres with an overnight stay before another 4 hour horseback ride up the mountain.

3. ‘Cerro Tololo’ means ‘Mountain in front of the abyss’. It was named for the sharp drop at the northern side of the mountain.

4. CTIO was built to withstand a richter scale 9 Earthquake which is equivalent to 20 trillion kg of dynamite!

5. The 4m Blanco hosts the Dark Energy camera (DECam), an instrument built by the Dark Energy Survey astronomers to solve the mystery of cosmic acceleration.

I will be spending 2 nights observing on DECam to complete the optical coverage of the southern XXL survey regions. This is my first time in Chile and hopefully not the last, the Large Synoptic Survey Telescope (LSST) will be built not far from here and is something I hope to work on in the future. LSST is expected to image 30Tb of data every night! That will definitely keep me busy!
Pictures to come shortly and fingers crossed for clear skies!

Finally, I would like to thank to Jean Marc at Air France who helped me tremendously to get on a flight to Chile after countless complications!