A powerful radio-wavelength laser light has been detected from deep space, at the longest distance ever detected. It’s a type of massless cosmic object called a megamaser, and its light traveled 5 billion light-years before it reached us here on Earth. The astronomers who discovered it using the MeerKAT radio telescope in South Africa named it Nkalakatha, a Zulu word meaning “great leader.”
This discovery has been accepted into Astrophysical Journal Letters and is available on the arXiv prepress server. “It is impressive that during just one night of observation, we actually found a record-breaking megamaser,” said astronomer Marcin Glowacki of the International Center for Radio Astronomy Research (ICRAR) Curtin University in Australia. Show how good the telescope is.
A maser is the microwave equivalent of a laser (light amplification by stimulated emission of radiation). Instead of emitting visible light, the maser emits microwaves and radio wavelengths that are stimulated and amplified. For an astrophysical maser, the processes that amplify light are cosmic; Planets, comets, clouds, and stars can all produce meses.
So a megamaser is a maser with some power. Among other things, active supermassive black holes can produce massive waves. When the data came from the first night of a 3,000-hour chart investigation, Glowacki and the team found a signature of a very specific type of megamaser, glowing at wavelengths amplified by catalyzed hydroxyl molecules, made up of an atom of hydrogen and a. Oxygen atom.
Massive hydroxyl compounds have a known production mechanism. They are emitted by galaxies that are in the process of colliding or have recently had a collision with another galaxy, and thus explode with star formation. The gravitational interactions of such a massive encounter compress the star-forming gas, causing it to collapse into newborn stars at an exponential rate. The source of the massive discovered by Glowacki and colleagues is a galaxy called WISEA J033046.26−275518.3, now known as Nkalakatha.
“When two galaxies like the Milky Way and Andromeda collide, rays of light emerge from the collision and can be seen at cosmic distances,” said astrophysicist Jeremy Darling of the University of Colorado. “Giant hydroxyl acts as bright lights telling us that colliding galaxies are producing new stars and fueling massive black holes.”
The MeerKAT survey is not designed to search for bulky GPS devices. It’s called “Looking at the Distant Universe with the Meerkat Array” (LADUMA), and it looks for a 21-centimeter wavelength emitted by neutral hydrogen in the early universe, which was stretched (redshift) due to the expansion of the universe. However, the wavelengths of the hydroxyl magmaser are 18 cm; When shifted to red, it is longer, and this signal transmitted to red is within the range detectable by the telescope array.
Since the sky region has been widely observed at other wavelengths, tracing a signal to a host galaxy was fairly straightforward. Nkalakatha is bright in infrared wavelengths and has a long tail on one side that glows brightly in radio waves, possibly as a result of the attraction to the gravitational interaction between the two now joined galaxies.
The team has already planned to go on the lookout for the cool stuff and expects to find several VIPs. “It is likely that Meerkat will double the known number of these rare phenomena,” Darling explained. “It was thought that galaxies merge a lot in the past, and the newly discovered giant hydroxyl system will allow us to test this hypothesis.”