A powerful new array of radio telescopes is being deployed for the first time this week, as the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile joins a global network of antennas poised to make some of the highest resolution images that astronomers have ever obtained. The improved level of detail is equivalent to being able to count the stitches on a baseball from 8,000 miles away.
– VLBI (Very Long Baseline Interferometry) now links radio telescopes spread across the globe into what is, in effect, a telescope the size of our planet
– extending the array to millimeter wavelengths achieved a further boost in resolving power.
The result is an order-of-magnitude increase in the sensitivity of the world’s millimeter VLBI networks.
gamma rays (over ~1 MeV)
hard X-rays (10-1000 keV)
soft X-rays (1-10 A)
EUV (~100 A)
UV (~1000 A)
visible (4000-7000 A — 400-700 nm)
near IR (~1 micron)
IR (10 microns)
THz (~100 microns–3000 GHz)
submillimeter (300 GHz – 700 GHz)
millimeter (30 GHz – 300 GHz)
microwave (3 GHz – 30 GHz)
decimeter (300 MHz – 3 GHz) (“cable” TV/UHF band)
meterwave (30 MHz – 300 MHz) (TV/FM/HF band)
dekameter (3 MHz – 30 MHz) (Shortwave
AM band (0.5 MHz – 1.7 MHz)
One of the goals of these new technological innovations is to image a black hole. This month, two international organizations are making observations that will allow scientists to construct such an image for the very first time. And the portrait they’re attempting to capture is close to home: Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way.
The black hole images from the data gathered this month will take months to prepare; researchers expect to publish the first results in 2018.
High-resolution science that will go far beyond the study of black holes. They will be able to make movies of the gas motions around stars that are still in the process of forming and map the outflows that occur from dying stars, both at a level of detail that has never been possible before.
The square kilometer array will be following the ALMA.
The Square Kilometre Array (SKA) is a large multi radio telescope project aimed to be built in Australia and South Africa. If built, it would have a total collecting area of approximately one square kilometer. It would operate over a wide range of frequencies and its size would make it 50 times more sensitive than any other radio instrument. It would require very high performance central computing engines and long-haul links with a capacity greater than the global Internet traffic.
It should be able to survey the sky more than ten thousand times faster than ever before.
With receiving stations extending out to distance of at least 3,000 kilometers (1,900 mi) from a concentrated central core, it would exploit radio astronomy’s ability to provide the highest resolution images in all astronomy. The SKA would be built in the southern hemisphere, in sub-Saharan states with cores in South Africa and Australia, where the view of the Milky Way Galaxy is best and radio interference least.
Construction of the SKA is scheduled to begin in 2018 for initial observations by 2020, but the construction budget is not secured at this stage. The SKA would be built in two phases, with Phase 1 (2018-2023) representing about 10% of the capability of the whole telescope.