Radio Waves

April 21, 2018.

Sorry. No pics from our first radio antenna site. Antennas of the Deep Space Network are in a secure site near Barstow, CA, and the public is no longer allowed access to them. But there is a nice museum in Barstow with interactive displays about their use. Along with sister antennas in Madrid and Canberra they receive the faint radio transmissions of spacecraft from Voyager to those of numerous younger missions.

Our second site, the Very Large Array (VLA), gives guided tours every third Saturday. The VLA is part of an international group that studies black holes and gas clouds. They receive low frequency, very low energy waves. (We were told that the total energy of all the waves received since 1980 was the same as that of a snowflake hitting the ground.) So a really wide antenna base is needed. How wide? Well, a radius of about 13 miles seems to be working.

But where can you find such a wide flat space? Don’t forget that it must also be at a high altitude, close enough to civilization to allow for a support staff and visiting scientists, but shielded from local radio noise. As it turns out, there’s an ideal spot near Socorro, NM.

Site prep began around 30 million years ago. Volcanos started popping off around an area high in the Colorado Plateau. As the land around crumbled and shifted, this area remained relatively flat. Later a lake formed. After the lake was gone its flat bed remained. Now here, at 6970′, surrounded by mountains that block local radio interference, the VLA listens.

The array is a large “Y” configuration. The SW and SE arms each stretch out 13 miles from the center. The northern arm is stopped at 11 miles by a large ravine. Each arm is a railroad track with antennas positioned beside it. All antennas are wired to a central location, where an operator directs their slow ballet of changes in azimuth and altitude.

One of the studies we learned about involved dwarf galaxy Henize 2-10. The research implies that massive black holes may be linked to the births of galaxies. Of course Henize is pretty far off. The radio waves studied were sent around the time volcanos were erupting here.

Are there burning questions you have about space gas or black holes? Maybe you want to study the “brand new” black hole that appeared in Cygnus A, 800 million light years away. You can submit a proposal to get time on the VLA. Proposals are accepted based on merit. Or you could just use the “Ask an astronomer” page on the VLA website.

Click here for the Deep Space Network website, and here for the VLA website.

* All pics are click to enlarge.