In stellar terms, the Trapezium Cluster is extremely young. The A, B, C and D stars are estimated to be only 1 million to 3 million years old. For comparison, our sun is approximately 4.6 billion years old. The full designations of these stars are:
- Theta¹ Orionis A
- Theta¹ Orionis B
- Theta¹ Orionis C
- Theta¹ Orionis D

There is also a fainter star, designated as Theta¹ Orionis E, which lies between the A and B stars, However resolving this star requires a level of detail that exceeded the capabilities of my telescope back then. In March of 2025, I purchased a new cooled deep-sky camera, the ZWO ASI2600MC Air. This camera has a smaller pixel size compared to my previous ZWO ASI294MC Pro camera. So maybe I am able to capture additional detail in this region during a future imaging attempt.

While doing research on Messier 42, I came across a Hubble Space Telescope (HST) image of Orion’s core, showing not one, but six protoplanetary disks within this stellar nursery. After examining the apparent size of these dusty spots, I decided to compare my own image of the nebula’s core with the HST image, to see if there was a small chance that one might be visible. To my surprise, I did indeed find one! Protoplanetary disk 106-417, which can be seen in the up close image in this blog post. Discovering an unexpected object in my own data is always a rewarding experience, and adds an extra layer of scientific depth to each image.

So what exactly is a protoplanetary disk, and why is it remarkable to see one in an image captured by an amateur astrophotographer here on our Earth? the answer is partly revealed in the termijn “proto”, meaning “earliest”. A protoplanetary disk consists of a molecular cloud of gas and dust that is collapsing under its own gravity. As it contracts, it forms a rotating, flattend disk with a newly formed protostar in its center. Disks like these are mostly composed of hydrogen and helium gas, the same elements from where stars are formed.

It is not possible for someone with a normal telescope to obverse the protostar itself, as it is deeply embedded within cold, dense gas. However, the James Web Space Telescope (JWST) can! With its ability to observe in the infrared portion of the electromagnetic spectrum, some that my equipment cannot, it can detect these hidden objects. Infrared photons emitted by the protostar are able to penetrate the thick surrounding material. Making the JWST an extraordinary tool for sudying early stellar evolution.

The protoplanetary disks near the core of the Orion Nebula are estimated to be around 300,000 years old. Slowly but surely the protostar at the center expels lighter gases toward the outer reions of the system, and the remaining dust particilars gradually unite to form planets. Near the inner regions of the disk, rocky planets, simulair to Mercury, Venus, Earth and Mars can develop. And the abundant hydrogen and helium gas in the outer regions can give rise to gas giants like Jupiter, Saturn, Uranus and Neptune.

In most cases, protoplanetary disks produce powerful jets emerging from the poles of the protostar. These jets form when large amounts of infalling material cannot be fully incorperated in the disk, and are instead ejected along the star’s rotational axis. The process resembles a cosmic whirlpool, with matter spiraling inward while excess material is ejected outward.