And also the stars

Hubble Frontier Fields view of MACSJ0717.5+3745

Over the northern summer of 2019, a teen fresh out of junior high school accepted an internship. He turned up for his first day and was shown his desk and introduced to the office machines and procedures.

On his second day, he spent considerable time honing his skills and learning how to use the technology. On day three, he did something that hit world news headlines for all the right reasons.

That intern was 17-year-old Wolf Cukier; he interned at Nasa’s Goddard Space Flight Center in Scarsdale, N.Y.; and he discovered an unknown planet, 6.9 times the size of Earth, the only known planet in its binary star system, 1,300 light years away. The discovery was finally verified on January 6.[1]

“It was awesome,” says Wolf. “The fact that I found something is cool.”

Wolf’s planet, TOI 1338 b, revolves around two of a very large number of stars, and (presumably) an even larger number of planets. And some of those stars are vastly larger than our entire solar system.

There’s much we don’t know about our universe, but one thing we do know is the approximate number of stars, stretching tens of billions of light years in every direction.[2]

A light year is the distance light travels in a year, in the vacuum of space; to get some perspective of the distances involved, remember that it takes about eight minutes and 20 seconds for light from the sun to reach Earth.

So… how many stars are there?

In an ideal world, we would count them all. But in practice, that won’t work. Our telescopes are limited in size, which in turn limits how many photons they can collect and the resolutions they can achieve.

Some of the Universe is obscured by intervening matter. And the more distant an object is, the fainter it appears; at some point, a source is too far away to be seen from Earth.

However, the longer you examine a single patch of sky, the more light is collected, and the more detail is revealed. That’s what the Hubble Space Telescope does, to the amazement of its first users:

Everywhere we looked, in all directions, there were galaxies. Not just a few, but thousands upon thousands of them. The Universe wasn’t empty and it wasn’t dark; it was full of light-emitting sources. As far as we were capable of seeing, stars and galaxies were clumped and clustered everywhere.

Now each patch of sky observed through Hubble is tiny, and it would take 32 million of them to cover all the possible directions we could look. Each patch displays about 5,500 galaxies, suggesting that there may be as many as 176 billion galaxies.

But that is a lower limit. Accounting for all the variables, including the effects of space-time, it is estimated that two trillion galaxies should exist within the observable Universe.

And since our galaxy, the Milky Way, is thought to contain about 100 billion stars,[3] it follows that two trillion galaxies represent an inconceivably large number of stars, and a vastly larger number of potential planets just waiting to be discovered by teenage interns in astronomy labs.

Which is why I love those four often overlooked words, hiding in plain sight, at the end of Genesis 1:16, where the Bible tells us that God created the sun to govern the day, and the moon to govern the night, “and also the stars.”

That’s a lot of work! Imagine how powerful God is! How creative God is! How much God loves matter, from subatomic particles to galaxies! And the extraordinary unity and diversity evident in the observable universe!

And how inexplicable, yet wonderful, that God should take note of our star, and our planet, and our individual lives, in demonstrating his love and mercy and grace to us in Jesus Christ his Son.

Creator God, though we may feel infinitesimally small and insignificant when we reflect on the universe you have made, we thank you that you have regarded us, and spoken clearly to us in the Bible, and through your Son. Help us to know you more intimately, and to understand the world you created more completely, and to care for it more thoughtfully. Amen.


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