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For a very long time, Mira A has been dying. Its existence was first noted by astronomers in 1596 after they observed that, in contrast to most stars that are visible to the unaided eye, it brightened and dimmed in a rhythmic manner. It has been researched, cataloged, and utilized for centuries as a point of reference to comprehend the behavior of massive, ancient red giants in their last stages of life. Then, right before Valentine’s Day in 2026, it did something that no model could have predicted: it ejected a cloud of gas and dust that was almost unbelievably shaped like a heart.
The mass of the cloud is about seven times that of Earth. To put that in a comprehensible context: The slow, gradual process of stellar mass loss causes Mira A to lose roughly one Earth mass every ten years. Here, the output was about 100 times greater than usual, and it arrived in what seemed to be an abrupt, asymmetrical burst. “We know that stars like Mira lose mass as they age, but we did not expect it to happen in such large and sudden bursts,” stated Theo Khouri, an astronomer at Chalmers University of Technology in Sweden who oversaw the analysis of observations gathered between 2015 and 2023 using the Very Large Telescope and ALMA in South America. Even though that statement is modest, it has a lot of weight when you take into account how much this specific star has been observed over the past 400 years.
| Star & Discovery — Key Information | |
|---|---|
| Star Name | Mira A — red giant variable star, prototype of “Mira variables” |
| Location | Constellation Cetus (the Whale) — approximately 300–400 light-years from Earth |
| First Documented Observation | 1596 — one of the longest-studied stars in astronomical history |
| Star Type | Red giant in late-stage life cycle — pulsating variable |
| Companion Star | Mira B — a white dwarf in binary orbit with Mira A |
| Mass Ejected in Recent Outburst | Seven times Earth’s mass — roughly 100 times greater than expected |
| Cloud Shape | Heart-shaped — two asymmetrical lobes of gas and dust expanding outward |
| Normal Mass-Loss Rate | Approximately one Earth mass per decade under typical conditions |
| Telescopes Used | Very Large Telescope (VLT) and ALMA — observations collected 2015 to 2023 |
| Lead Researcher | Theo Khouri, astronomer — Chalmers University of Technology, Sweden |
| Key Surprise | Ejection speed and volume far exceeded all existing models for this class of star |
| Cloud Contents | Heavy elements — carbon, oxygen, and other building blocks of planets and potentially life |
| Next Observation Focus | Monitoring whether the expanding cloud begins to affect companion star Mira B |
This is truly strange to look at because of the cloud’s structure. When the data arrived, astronomers were drawn to the distinctive heart-shaped lobes of material that billowed outward from the star, with gas filling the interior volume and dust concentrated almost entirely along the outer edges. For a star of Mira’s kind, most mass-loss models would predict a clean, spherical shell, but this was not the case. The explanation for the asymmetry is still incomplete. Khouri observed that rather than radiating uniformly in every direction, the star seems to illuminate the dust around it unevenly, acting like a lighthouse sweeping its beam in erratic patterns. Just that observation raises a number of questions regarding how material is actually driven off the surfaces of aging red giants by their internal pulsations.
This cloud’s composition has a subtle significance. Carbon, oxygen, and other heavy elements found in the ejected material are precisely the kinds of compounds from which planets form and from which life eventually assembled itself, at least on Earth. Every time a star like Mira A loses its outer layers, it releases material into the interstellar medium that could eventually find its way into a new planetary system. Astronomers have a window into a cycle that has been repeating throughout the galaxy for billions of years by witnessing that process in real time, in detail, at a distance of just a few hundred light-years. Looking at the pictures of a glowing, lopsided heart hanging in the dark and broadcasting its contents outward at speeds that even the people who built the instruments to measure it were surprised by, it’s difficult not to feel the weight of that.
In this, Mira A is not by herself. It is accompanied by Mira B, a white dwarf that is circling the giant and has already started to collect some of the material being shed. Khouri’s team is keeping a close eye on that interaction, pointing out that as the expanding cloud gets bigger, it might begin to impact the companion in previously unseen ways. There could be intriguing repercussions from a white dwarf accumulating material from a red giant neighbor in an exceptionally dense cloud, but it’s still unclear exactly what those might be. It is evident that there are still surprises to be found in the astronomical record of Mira A, a star that has existed longer than the majority of scientific establishments.
