Go to to an Alien World



6 August 2019

The landscape of Chajnantor.
Brian Koberlein
The panorama of Chajnantor.

Standing on the excessive website of ALMA is like standing on one other world. Sandy gravel marks the rolling plain beneath an oddly blue sky. The air is skinny and dry, with such little oxygen it’s important to put on an oxygen tank. Throughout the plain, sensible white antenna dishes dot the panorama. They’re nestled in a plateau surrounded by mountains. It seems extra just like the fictional desert planet of Dune than our personal homeworld.

At 16,500 ft, ALMA is the very best radio telescope on the planet. The situation of ALMA was chosen by the requirements of astrophysics and the happenstance of terrestrial geography. The first mission of ALMA is to look at the chilly and distant gasoline and mud of the cosmos. The form of materials that floats in interstellar house and huddles round younger stars as they start to kind planetary programs. This gasoline and mud emits a faint mild with wavelengths a few millimeter lengthy. These wavelengths of radio and microwave mild are absorbed by water vapor in Earth’s ambiance, to allow them to solely be seen from house, or at excessive elevations the place the air is skinny and dry. The best and driest plateau on Earth is within the Atacama area of Northern Chile. Referred to as Chajnantor plateau, it’s the excellent location for this sort of radio astronomy. Clear skies, with a fairly flat space massive sufficient for greater than 5 dozen radio antennas.

One of the ALMA radio antennas.
Brian Koberlein
One of many ALMA radio antennas.

Sustaining and working ALMA observatory is a big problem. Winter storms can pummel the area, and excessive winds can shut down operations at occasions. The surroundings is so harsh that staff should go strict medical exams to work on website. The location is closed to most of the people. Anybody can go to the low website at 10,000 ft, the place the residences and management heart are situated, however the antennas function on the excessive website, and solely guests with particular approval are allowed. Even then, it’s important to go a fundamental well being check. Not everybody passes. On my first go to to ALMA I didn’t.

In 2015 I used to be a part of an astronomy outreach group visiting observatories throughout Chile. ALMA was the final cease on our tour. It was an opportunity to go to one of the crucial distant observatories on this planet. When you go the bodily. The important thing issues they measure are blood stress, coronary heart price and oxygen stage. With a rise in altitude the quantity of oxygen within the air drops. On the excessive website, oxygen ranges are half that sea stage. In consequence, your physique goes into stress mode, elevating your coronary heart price and blood stress as it really works more durable to maintain you acutely aware. In probably the most excessive eventualities, this will result in issues like a stroke or coronary heart assault. So if the medical expert thinks your physique is simply too careworn, you aren’t accredited. Interval. I wasn’t accredited. Everybody else in my group was. I needed to wait on the low website as they went to the excessive website. They stated it was superb. I wouldn’t know. I used to be the boy they left behind.

A selfie at ALMA.
Brian Koberlein
A selfie at ALMA.

Earlier this summer season I had the possibility to go to ALMA once more. It was not with out trepidation that I arrived at low website for one more medical verify. As I sat there linked to the units, I puzzled if I might be denied once more. Some folks by no means go the check. It has much less to do along with your age or whether or not you run each weekend, and extra with the whims of your biology. Some folks don’t react nicely to excessive elevations. Others have much less of a problem with it.

However this time I handed. I used to be given my obligatory papers and an oxygen tank to be worn for your entire journey up and again. After the 30-minute drive to the excessive website you’re checked once more, principally to substantiate that your oxygen stage is passable. After that, you’ll be able to spend about an hour among the many antenna dishes of ALMA.

It is just while you step exterior of the buildings on the excessive website that you just understand simply how far-off you’re out of your place of origin. The sky is sensible blue, however in some way unsuitable. It’s each brighter and darker than you count on it to be. It casts an odd layer of coloration upon the gray and crimson rocks of the land. The mountains on the horizon appear each shut and distant in a manner that’s tough to clarify. Even along with your oxygen tank, the air appears faint and chilly. It’s a wondrous website of desolation, dotted with a number of the most subtle radio dishes on this planet. A view few on this planet will ever see.

And in the event you pay attention very carefully, you may hear a small voice behind your head:

Arrakis. Dune. Desert planet.

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