NGC 2264 photographed from Lakeway, Texas with a ZWO Seestar S50, shown with south up: the small dark Cone Nebula sits in red glowing gas at the top, its tip pointing down toward the cluster, a loose triangle of stars and red nebula widens below it like a tree, and the bright blue-white star S Monocerotis sits at the base with a pale blue haze beside it.

NGC 2264 — The Cone and the Christmas Tree

A living entry: one night, turned south-up so the tree stands upright

TelescopeDarth Vader (ZWO Seestar S50)
Integration176 minutes
LocationLakeway, TX
SkyBortle 6
CapturedNov 5, 2026
PhotoKyle Eberly · © 2026
ProcessingOne night, November 5, shot by the telescope robot: 527 twenty-second exposures through the dual-band filter, 2.9 hours, after the target cleared the trees around half past midnight. About a quarter of the frames were thrown out by the telescope itself for trailed stars: this target sits almost on the celestial equator, where a small error in pointing the mount at the pole smears stars fastest. The picture is shown south up, the way this cluster is usually printed, so the stars read as a tree with the Cone at its tip. It is rotated, not mirrored: this is the real sky, turned upside down. Processed from the telescope’s 16-bit stack with the same custom Python pipeline as the rest of this journal.

What you're looking at

NGC 2264 is a young star cluster and the gas cloud it is still being born from, about 2,500 light-years away in Monoceros, the Unicorn. Its brightest star, S Monocerotis, is a hot, massive star tens of thousands of times as bright as the Sun; it sits at the base of the tree here.

The Cone is a pillar of cold, dark dust, about seven light-years long, its tip pointing toward the hot stars of the cluster. Their light is eating away at the gas around it; the Cone survives because it is denser than its surroundings, the same way the Elephant’s Trunk and the Pillars of Creation survive.

The stars that make up the tree are only a few million years old, younger than almost anything else on this site. Some of them are still settling into stable stars.

The lesson

This one only looks like a Christmas tree upside down. Photographed with north up, the way the telescope sees it, the tree stands on its tip.

Nothing about the data changed; I turned the frame around so a reader sees what astronomers have seen in it for a century. Rotating a picture is fair; mirroring it would put stars where they aren’t.

The orientation you present something in is part of the message. Choose it on purpose, and say what you did.

Object data

Catalog: NGC 2264 · Cone Nebula · Christmas Tree Cluster
Constellation: Monoceros
Type: Young open cluster in an emission and dark nebula
Distance: ~2,500 light-years
Brightest star: S Monocerotis, at the base of the tree
Orientation: South up (rotated 180°, not mirrored)
Status: LIVING ENTRY — 2.9 hours from one night, deepening this week

What you're looking at

The lesson

Object data

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