Americans traditionally take a moment to be thankful for the good things in life on Thanksgiving. It takes many different forms for different people, including family, friends, health, food, and sometimes just a general appreciation for life.
I'm thankful for the Hubble Space Telescope.
There are a lot of reasons, including being affiliated with it, getting a degree and a job working with it for a long time.
It changed the way we view the Universe. It brought astronomy into the public consciousness because of its keen and unfettered vision and the scientists who pointed it and the visual artists who created its stunning Cosmic portraits. They finally got to see the magnificence over our heads, the way they had imagined it for decades.
It changed the way we view the Universe.
A young star just getting its start in the universe is named J1672835.29-763111.64, and it is an example.
J1672 is a star still in the process of forming, surrounded by material from which it is being born. It has a mass of 1/3 that of the Sun, and is only 1% as bright as the Sun, so it is probably a red dwarf. It's part of a complex of star-forming clouds called IC 2631, which is 500 light years from Earth.
This image was taken as part of a larger program to take snapshots of young stars. The survey will look for changes in the nebulosity around them and in the brightness of the stars over time, as shown by the observations of J1672 of the Spitzer Space Telescope. The period is consistent with how fast young stars spin, and it could be due to starspots, which are magnetic phenomena. Huge spots, far larger than is realistic, are implied by the large variation in brightness.
The variability may be due to outside influences. A disk of material is very common in still-forming stars. The material falling from the cloud of gas and dust can be used to form planets around the star, and we call them proplyds. The disks are sometimes warped like the brim of a fedora or a cowboy hat. The star's light could be partially blocked by this. The star gets redder when it gets fainter because of the dust in the disk.
That's nice evidence of a disk. You can see more evidence for a disk. Take a second look at the image. There is a dark shadow around the star.
That is a shadow. The disk is illuminated by J1672 and has a shadow on it. The disk is too small to be seen on this scale, but the shadow it throws is huge.
The shadow may change over time if the disk is causing the star's brightness to change. Further observations may reveal that.
This has been done before. Hubble observations show a shadow on the material around the star HBC , which is similar to the shadow J1672 cast.
That's amazing. When I think of stars, I think of them as unchanging, or at least changing in ways that are obscure and difficult to measure. You can see it here.
The Hubble observations of the magnificent Orion Nebula gave us the first clue to proplyds, revealing dozens of them cocooning young stars in the nebula ready to fledge. The telescopes that can see in theIR were used to learn more about them.
This is not a strange idea. I want you to look at that image again. You were 4.5 billion years ago. Not metaphorically, not metaphorically or poetically, but in a very real and actual sense. The material collapsing and gathering itself, a disk forming in the center, the Sun forming in the center of that, the disk filled with tiny grains of dust and gas, growing ever larger until they hit each other.
And then Earth. Eventually, you. Everyone you know or have heard of, and everything you see around you. All of it.
Hubble revealed all in this amazing image.
There are biggerscopes that can see at a wavelength Hubble can't, and they are designed to investigate objects that Hubble can't.
Hubble brought it home to us.
I'm very thankful for that.
Happy Thanksgiving.
Astronomers can use stars' coordinates on the sky to figure out which is which in an image. Different units can cause confusion. The first number is referred to as the hours and the second number is referred to as the longitudinal coordinates in degrees. This star is in the system for 11 hours. It took me a while to find this star in other papers because different names were used.
