Across the Universe
February has brought a bevy of news about the building blocks of planets from Maunakea.
On Feb. 10, the WM Keck Observatory announced that a team of astronomers from UCLA used the Keck telescope to discover an object with carbon, nitrogen, oxygen and hydrogen — the building blocks of life. The object known as WD 1425+540 is a white dwarf, the leftover core of a star originally similar in size to our own sun. The team observed an atmosphere rich in carbon and nitrogen as well as oxygen and hydrogen, the components of water. WD 1425+540 is the first white dwarf found with nitrogen in its atmosphere. Generally, the strong gravity of white dwarfs causes heavier elements like carbon, oxygen and nitrogen to sink into the interior of the star where they cannot be observed from Earth.
Astronomers theorize that a small, icy and rocky body crashed into the star in the past 100,000 years or so. The object, similar to Kupier Belt objects in our own solar system, likely contained the carbon, nitrogen and water. When the object crashed, it added its materials to the atmosphere of the star.
Why is this discovery important? The signatures of carbon, nitrogen, oxygen and hydrogen in the star provide important evidence of icy bodies orbiting the star. While we know these objects are common in our own solar system, this is the first evidence of their existence outside our solar system. These icy bodies, both in our solar system and other planetary systems, may be the origins of the water, nitrogen and carbon needed for life.
Moving from the building blocks of life to the search for extrasolar planets or exoplanets
The Subaru Telescope announced the newest upgrade to their suite of instruments last week, the Subaru Corongraphic Extreme Adaptive Optics or SCExAO. SCExAO, which has been growing constantly with new modules, allows astronomers to take sharper images of space by compensating for turbulent air in the atmosphere. Think of a bumpy airplane ride. That same turbulence causes distortions in the light that arrives from space. These distortions can make the stars appear blurry and the turbulence changes on a minute-by-minute or even second-by-second basis. SCExAO works with a mirror that can correct these distortions. It compensates more precisely and faster than the current AO system at Subaru.
Without the blurring effects of the atmosphere, astronomers using the Subaru Telescope can peer closer to stars and hopefully discover massive planets like Jupiter orbiting closer than Mercury as well as fainter planets.
Astronomers used some of the first observations with SECxAO to find a debris disk around a distant star. The debris is likely the leftover icy remnants from planet formation around the star. This newly discovered debris disk may be the youngest such disk ever discovered, giving astronomers new insights into how big, icy planets form. The objects in the debris disk would be similar to those we see in the Kuiper Belt surrounding our own solar system.
And as we learned from the Keck discovery at the top of the article, these icy bodies may contain nitrogen, carbon, water and hydrogen — the building blocks of life.
With each discovery and new instrument on Maunakea, astronomers get closer and closer to the discovery of an Earth-like planet around a distant star or even life in the Universe.