This Is the Best Image Ever of a Planet Being Born
Planets in the making. Image: ALMA (NRAO/ESO/NAOJ); C. Brogan, B. Saxton (NRAO/AUI/NSF)


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This Is the Best Image Ever of a Planet Being Born

Which is just what you’d expect from the most powerful, largest, and most expensive telescope on Earth.
November 6, 2014, 3:51pm

The HL Tau star system is giving birth to a litter of planets, and thanks to the Atacama Large Millimeter Array (ALMA) in Chile, we have an extraordinary baby picture to fawn over. Take a look at this bad boy:

"The first time I saw this image I thought it was actually probably a simulation," said Tony Beasley, the director of the National Radio Astronomy Observatory, in a video about the image. "It was just way too good."


"I think that as many of us were building ALMA, we knew it would be capable of making images like this," he continued. "But to actually see the first one come off the instrument is a landmark event for many of us."

Indeed, the image clearly shows the concentric rings marking where planetesimals are beginning to accumulate and mature into full planets. Given that HL Tau is a young Sun-like star located a full 450 light years away, this resolution of 35 milliarcseconds is astounding. In familiar Earth-based terms, the resolution is roughly the equivalent of producing a high-res image of a penny from over 110 kilometers away.

ALMA achieves this unprecedented focus with its large-scale design. It is composed of 66 antennae scattered across the Atacama desert plateau in Chile, which is 5,000 feet above sea level. The high, dry location is perfect for uninterrupted star-gazing, and the long distances between each antennae—which can be up to 15 kilometers—create an enormous aperture for deep space viewing.

As captivating as the image is, it's not a huge shocker that ALMA is already producing this quality of work. When it began operations in March 2013, it became is the largest, most powerful telescope on Earth, and the most expensive ground-based telescope ever built. It was designed and built by an enormous international collaboration of scientists, and will be studying everything from dark matter to exoplanet weather to star birth.

It looks like this stellar image of planetary formation will be the first of many "best images ever" to come from the newest kid on the telescopic block.