Welcome to Three Alpha! Since last time: In the Solar System, NASA has lost contact with the MAVEN Mars orbiter and is attempting to re-establish contact (at the time of writing, on Friday); in the Galaxy, the Sun had a close encounter with two large stars 4.4 million years ago; and in the Universe, a nearby cosmic filament is one of the largest rotating structures ever found.

Meanwhile, in this edition of the newsletter we’re focusing on new images from Hubble of a young solar system. Read on for more…

A new image of a new solar system

Would you like a sandwich? Before you answer, you should know that instead of bread, it’s made mostly of dust. And the filling is also dust. With a young star somewhere in the middle. And the whole thing has maybe twice the mass of the Sun and a temperature of 8,000 degrees. Perhaps you’d like to just look at it instead:

This is Dracula’s Chivito, a protoplanetary disk named jointly after the national sandwich of Uruguay and the national vampire of Transylvania, the birthplaces of two of the astronomers who discovered it (Ciprian Berghea and Ana Mosquera).

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Formally known as IRAS 23077+6707, the object has been studied since the early 90s, but we’re only just learning about its nature. The name Dracula’s Chivito comes from a paper published last year. This new photo was taken by Hubble and published just a few weeks ago in a paper accepted for publication in the Astrophysical Journal.

A protoplanetary disk is a new solar system in the process of forming. Stars and the planets that orbit them all form from the same clouds of gas and dust. The star forms first, and then the planets (and astroids and everything else) form from what is left. The whole thing looks something like this:

Dracula’s Chivito is one of a few protoplanetary disks which we see edge-on. They all tend to look a little like sandwiches from that angle (another is called Gomez’s Hamburger). The dark band running diagonally across the middle of the above image is the disk itself. It is dense and blocks most of the light from the young protostar. Either side of that, we see the thinner upper/lower parts of the disk, illuminated by light from the star scattered by the thinner dust in those areas. Dracula’s Chivito is also the largest protoplanetary disk in the sky (in terms of how large it appears to us), being 15 arc seconds across (about the same as Saturn without the rings) and about 600-1,000 light years away. That means we can see more detail in its disk than in others.

There are many unknowns about the details of how stars and their planets form, so seeing new details of a system in the process of forming is helpful. In particular astronomers can compare what we see to the various theoretical models and narrow down things like how opaque the dust is (which affects the temperature, influencing how it all behaves) and how quickly the dust settles down into the disk (affecting how planets form around the young star). This new imagery is helpful, but more data is required to really work out the details.

Finally

Speaking of new Hubble images, check out this amazing shot of the interstellar comet 3I/ATLAS:

What is Three Alpha? Other than being the name of the newsletter you’re reading now, the name “three alpha” comes from the triple-alpha process, a nuclear chain reaction in stars which turns helium into carbon. Read more here.

Who writes this? My name is Dr. Adam McMaster. I’m an astronomer in the UK, where I mainly work on finding black holes. You can find me on BlueSky, @adammc.space.

Let me know what you think! You can send comments and feedback by hitting reply or by emailing [email protected].