This week: Science! But not the linguistic kind! Or, at least, not as much. Instead we’re looking up and gazing out at the stars via the James Webb Space Telescope. And something to do with Einstein? Let’s talk about it.
Gravitational Lens
Last week, NASA released the first image1 from the James Webb Space Telescope, Webb' 1st Deep Field2, an impossibly tiny sliver of the sky yet an immensely powerful look at just how vast the universe is. The image itself is said to cover an area of the sky about the size of a grain of sand if held at arm's length between your fingers. That image shows hundreds of galaxies dating back to the earliest days of the universe3.
I was in class when the first image came in. I immediately showed it to my students and re-wrote my lesson plan on the fly to include as much discussion about the image as possible. We talked about the telescope itself, we compared the Webb image to an earlier photo from Hubble, and we talked about the questions4 we might be able to answer because of this new technology and science. And I freaking love that we live in an age5 where I can do that.
But I'm not an astronomer. I'm a fan, an enthusiast, and I do my best, but... Every time there's some exciting new plot development regarding space and astronomy, I do all the required reading. I take notes. I get as good a surface level understanding of things as I can get. And then someone asks a question and away we go, down the rabbit hole, past the Mad Hatter's tea party, past the Red Queen and her court, and way out the other side of Wonderland into the even-more-unknown.
This time, as I was reading one of the many, many Reddit threads about the first Webb image, someone said, "hey, there's an Einstein Cross!" and off we go...
Astronomy.com6 regarding the original Einstein Cross:
the Einstein Cross, which is the quadruply lensed quasar Q2237+030. This object, 8 billion light-years away, happens to lie precisely behind a foreground galaxy named ZW 2237+030, which itself has come to be called Huchra’s Lens. Its gravity intercepts the quasar’s image and breaks its light into four separate, complete copies, creating a nearly perfect cross. The barely visible lensing galaxy appears at its center.
And Wikipedia, on gravitational lensing:
A gravitational lens is a distribution of matter (such as a cluster of galaxies) between a distant light source and an observer that is capable of bending the light from the source as the light travels toward the observer. This effect is known as gravitational lensing, and the amount of bending is one of the predictions of Albert Einstein's general theory of relativity.
In other words, an Einstein Cross is formed when a pulsar or other object is positioned directly behind a larger object, like a galaxy, at a position where we can observe it. The foreground galaxy acts as a lens, magnifying the light of the background object. However, that light is bent around the foreground object in such a way that it appears as four distinct points of light, making a cross shape.
Like many things in both physics and astronomy, this idea was largely theoretical until suddenly, it wasn't. Thus when the first cross was formed it was dubbed "The Einstein Cross." But then another was discovered and another and then another. In fact, as of 2021, more than 60 had been discovered; with the first few images from the James Webb, the count is sure to be much, much higher.
But aside from just being cool, the fact that so many have been found and that new ones appear in the Webb’s 1st Deep Field is important because it gives us more points in the data set. From there we can extrapolate, predict, and search for ever more new discoveries that can assist us in understanding the way our universe formed. And that understanding is crucial for us as a species if we are to change and adapt in ways that allow for a longer, better future7.
There's a lot more to be said here, but as I said in the beginning, I'm not an astronomer, I'm just a fan, so I'm going to stop before I make too-glaring an error. Instead, this week's rabbit hole is going to be a little bit longer so I can share some of the news stories I found interesting or helpful.
In the meantime, go look at the stars and take a moment to let yourself be amazed at the impossible vastness of the universe we live in.
Down the Rabbit Hole:
As I said, this week the rabbit hole is further reading about the James Webb Telescope, the first images, and space in general. Enjoy!
NASA’s Webb Delivers Deepest Infrared Image of the Universe Yet
James Webb Space Telescope: An astronomer explains the stunning, newly released 1st images
Why the new James Webb Space Telescope images are so important for science
How the James Webb Space Telescope's first colour images were made
From the Archives:
This week, the archives are going to go all the way back to December, 2020, when I talked about how space has become a family hobby via our backyard telescope and trips to the science museum:
91 Days:
The 91 Days project is going strong. You can read up on the project, see how it’s going, or join in by following the links below. It’s a lot of fun so far and I’d love to see how other people do with the challenge.
Which probably isn’t news. Unless you've been living under a rock. In which case - no judgement. It's a hard world and it seems to be getting harder all the time. If you need to hide under a rock, then do it, man. Stay safe and cozy down there. All this nonsense will still be here when you're more able to deal with it.
You absolutely should go and download the full-size image. It is really something like you’ve never seen before. Plus, it’s a lot easier to see the Einstein Crosses that way.
Give or take a few billion years.
Aliens, bro, where are they?
Even if it sometimes feels like the rest of the world is a dumpster fire being fueled by a malevolent cabal of patriarchal, capitalist, oligarchs, it's good to be reminded that we, as a species can rise above our innate tendency towards self-sabotage and examine the universe around us with curious awe.
The entire article is well worth reading. It provides an excellent and easy-to-understand history of the original Einstein Cross and its importance.
Count me amongst those who believes we must become a multi-planet species if we’re to survive the impossibly long odds that are stacked against us. Remember, the dinosaurs were here far longer than we have been…