Four orange laser beams blaze through the Milky Way while an angry purple nebula transfixes us with its death stare. Happily, Earth isn’t doomed; actually it’s an Earthly telescope that’s launching the lasers from the European Southern Observatory (ESO).
Dubbed ESO’s picture of the week, this shot seems like a cosmic battle to the death but it actually captures an ingenious astronomical trick that scientists use to see across time & space. The purple star system pictured here is the Carina Nebula, sometimes referred as the Eta Carinae nebula in honor of its most famous star system, Eta Carinae, actually a pair of two giant stars, that has been steadily exploding in a spectacular eruption of gas and dust for nearly 200 years. Though the system is found about 7500 light years from Earth, this brightening explosion has rendered it one among the most luminous star systems in Milky Way.
Seeing that far into space are often tricky, even when gazing at one among our galaxy’s brightest objects through one among Earth’s mightiest telescopes (in this case, the ESO’s Very Large Telescope located in Chile). One niggling problem: Earth’s gassy atmosphere always gets in the way by blurring & distorting the view of celestial objects.
That’s where the lasers come-in. According to ESO, scientists fire these lasers from one among the Very Large Telescope component pieces to simulate distant stars (Sodium particles in the atmosphere cause the beams to glow orange). Astronomers then focus on these artificial stars to find out what proportion the beams are being blurred by Earth’s atmosphere. By practicing with fake stars, astronomers can more-effectively calibrate the telescope to correct for atmospheric blurring when watching real stars, galaxies & explosive objects like Eta Carinae, consistent with the ESO.
So, to summarize: Earth scientists are actively shooting lasers into the heart of an exploding star system but only in order that they can get to understand it better. In our strange & delightful Milky Way, it is just the neighborly thing to do .