With over 2 decades of Hubble observations, including in ultraviolet light, astronomers have newly revealed some striking features, including streaks (in blue) emerging from the lower-left lobe. These streaks are created when the star’s light rays poke through the dust clumps scattered along the bubble’s surface. Wherever the ultraviolet light strikes the dense dust, it leaves a long, thin shadow that extends beyond the lobe into the surrounding gas. (NASA, ESA, N. SMITH (UNIVERSITY OF ARIZONA), AND J. MORSE (BOLDLYGO INSTITUTE))

This Is How Eta Carinae Survived A Near-Supernova Eruption

The most famous ‘supernova impostor’ of all could have died back in the 1840s. Here’s what we think kept it alive.

In all of astronomy, no stellar event releases more energy than a supernova.

An animation sequence of the 17th century supernova in the constellation of Cassiopeia. This explosion, despite occurring in the Milky Way and about 60–70 years after 1604, could not be seen with the naked eye due to the intervening dust. Surrounding material plus continued emission of EM radiation both play a role in the remnant’s continued illumination. A supernova is the typical fate for a star greater than about 10 solar masses, although there are some exceptions. (NASA, ESA, AND THE HUBBLE HERITAGE STSCI/AURA)-ESA/HUBBLE COLLABORATION. ACKNOWLEDGEMENT: ROBERT A. FESEN (DARTMOUTH COLLEGE, USA) AND JAMES LONG (ESA/HUBBLE))

Humanity hasn’t witnessed a naked-eye supernova within our galaxy since 1604, but Eta Carinae came close.

In 1843, previously modest star Eta Carinae brightened to become the 2nd brightest object in the sky, ahead of Canopus (shown here) and trailing only Sirius. Gradually, over the next 13 years or so, it faded until it finally became visible in telescopes only. (CELESTIA USER HENRYKUS)

In 1843, it brightened to become the second brightest star in the sky, gradually fading away by 1857.

This infrared light image showcases the large Carina nebula, which houses Eta Carinae at the lower left. The gas and dust loops visible arise not only from material blown off from Eta Carinae itself, but also from the material of the larger star-forming region that spawned it millions of years ago. Other new, nearby stars are also visible, showcasing the power of this star-forming region. (ESO / VERY LARGE TELESCOPE / T. PREIBISCH ET AL.)

Almost as much energy was released as in standard supernovae, but Eta Carinae remained intact.