Deep into the darkness

There is something special hiding in the Southern constellation Grus, the crane. Directly North of the second magnitude red giant Tiaki and about 4.5 billion light years away is a galaxy cluster known as Abell S1063. It’s what’s called a strong gravitational lens: an object massive enough to not only bend the light of more distant objects, but one that actually focuses that light into recognisable images, unveiling the otherwise unseeable. The full power of JWST was recently focused on Abell S1063 for a whopping 120 hours of combined observations. That’s the longest JWST has observed a single target, and the results are breathtaking:

To say there is a lot in this image would be quite the understatement. In the centre of the cluster is a huge elliptical galaxy, which appears as diffuse white light. Most of the objects you can see surrounding the elliptical galaxy are other galaxies in the cluster. The handful of objects struck through by distinctive straight lines are stars in the foreground, which are bright enough to create a diffraction pattern from the telescope’s mirrors. And the red, curved streaks? Those are the stretched, distorted images of galaxies located, far, far in the distance. Those are the ones we’re seeing thanks to the gravitational lensing effect.

This image is what’s called a deep field. That’s when a small area is imaged with a very long exposure, usually by combining multiple exposures together. Depth here refers to how far we’re able to see. A deep field literally allows us to see deeper into space, and also deeper into time because of the finite speed of light. The lensed galaxies we’re seeing thanks to Abell S1063 existed just 200 million years after the Big Bang (which was 13.8 billion years ago).

The Hubble Space Telescope has famously also produced several deep fields. My favourite is called the Hubble Ultra-Deep Field (I have a poster-sized version of it on my wall):

Like the Abell S1063 images, almost everything you see there is a galaxy. This image covers an area about a tenth of the size of the full Moon and contains an astonishing 10,000 galaxies. I could just sit and stare at this image for hours (that’s not hypothetical; I’ve done that), and there’s still always something new to find in there.

A few days after the Abell S1063 image was released, another new JWST deep field was released which puts the Hubble Ultra-Deep Field to shame. It’s called COSMOS-Web, it covers an area of the sky larger than the full Moon, and is the result of 255 hours of combined observations. It contains a jaw-dropping total of 780,000 galaxies. Here’s part of the image, which honestly doesn’t do it justice:

There’s also a great interactive version available.

To me, images like these are the embodiment of one of the best aspects of humanity: our curiosity. An untold amount of time, effort, and ingenuity went into designing, building, and operating the instruments which make these images possible. We break new ground and push through the boundaries of what our technology allows us to do. Why? To look. To see what is there. To discern the faintest of lights in the darkness and to try to understand them. We peer into the darkness, not with fear, but with a desire to know what’s out there.

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In the News

Solar System

• A new dwarf planet on a highly elliptical orbit has been discovered in the outer solar system, named 2017 OF201, making it less likely that the hypothetical Planet Nine really exists. [New York Times, New Scientist, Sky & Telescope]

• Earth’s core might be leaking! Rocks in Canada contain large amounts of certain isotopes which might have come from the planet’s core. [Nature]

• Amazing video of the Sun’s corona, thanks to adaptive optics. This works by measuring the turbulence in the atmosphere and reshaping the telescope’s mirror in real time to compensate. This is the first time this has been used on the Solar corona. [Space.com, Universe Today, Earth.com]

• MAVEN has observed argon atoms being knocked out of Mars’ atmosphere by the solar wind, in a process called “sputtering” that explains how Mars lost so much of its atmosphere and its liquid water. [NASA, Phys.org]

• Different types of ice found on Europa’s surface might mean water is erupting from below, partly driven by tidal heating from Jupiter’s gravity. [Universe Today]

• A new reason that Starlink is terrible for astronomy: they are flooding radio telescopes with interference, despite attempts to stop it from happening. [New Scientist]

Galaxy

• Radio emissions from long-period radio transients change more slowly than normal radio variations, and we don’t really know what causes that. For the first time, observations of one transient show that it also varies in X-rays at the same time, ruling out some options but not solving the mystery. [NASA, Scientific American, Science Daily]

• The first measurements of the polarisaton of X-rays from a magnetar just after an outburst. Polarisation is affected by magnetic fields, which means this gives clues about what was happening to the magnetar during the outburst. [Space.com, Phys.org]

• The Very Large Telescope has imaged a protoplanetary disk, which contains a probable gas giant in the process of forming, along with rings and spiral arms which closely match predictions of what a young planet like this should do to the disk. [ESO, Phys.org, Orbital Today]

• A Saturn-like gas giant orbiting a tiny red dwarf star is an unlikely combination that might mean we don’t quite understand how planets form. [Universe Today, Science Daily]

Universe

• There's some disagreement about whether the Milky Way and Andromeda will collide, or whether the influence of the Large Magellanic Cloud will avert the collision. [Science News, ESA, STScI]

• The Squid galaxy seems to be producing neutrinos in an unexpected way that results in much less gamma ray emissions. [SciTechDaily]

• A tidal disruption event, when a black hole tears apart a star, has been detected in a galaxy that’s merging with another. Mergers are thought to trigger tidal disruption events like this, but this is only the second one to actually be seen in a merger. [Space.com]

• Combined radio and X-ray observations have been used to study two jets from supermassive black holes, about 3 billion years after the Big Bang. The jets are more powerful than expected, travelling at almost the speed of light and stretching for over 300,000 light years. [Chandra/Harvard, Universe Today]

• The supermassive black hole in M87 is spinning at 80% of the maximum and is consuming 0.4 solar masses of matter per year, according to new analysis of the Event Horizon Telescope data that looks at the Doppler boosting and magnetic fields of the accretion disk. [Universe Today, Live Science]

• New JWST observations of known low-luminosity quasars sugests they may be the missing link between classical quasars and little red dots. There are signs of feeding black holes, like in classical quasars, while the colour is similar to the little red dots. [Live Science]

Finally

Check out the Sun’s poles, courtesy of Solar Orbiter:

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].