Sirius

NOTICE: This page is a Work in Progress as much of the lore/Development for the game is yet to be established.

Sirius (also known as Alpha Canis Majoris or the Dog Star) is the brightest star visible in Earth's night sky and one of the closest star systems to Sol. Located approximately 8.6 light-years away in the constellation Canis Major, Sirius is actually a binary star system consisting of a bright primary star (Sirius A) and a faint white dwarf companion (Sirius B).

Characteristics

Sirius
Stellar Data
Common Name	Sirius (Dog Star)
System	Sirius System (Alpha Canis Majoris)
Location (Galactic Coordinates)	-26676,-5,69
Object Class	Unknown
Spectral Class	A1V (Sirius A) / DA2 (Sirius B)
Temperature (Surface)	~9,940 K (Sirius A) / ~25,200 K (Sirius B)
Mass	~2.06 M☉ (Sirius A) / ~1.02 M☉ (Sirius B)
Radius	~1.71 R☉ (Sirius A) / ~0.0084 R☉ (Sirius B)
Luminosity	~25.4 L☉ (Sirius A) / ~0.026 L☉ (Sirius B)
Habitable Zone	~4.8 AU – ~6.9 AU (Sirius A)
Planets	14
Roche Limit	Unknown
Hill Radius	Unknown
2000K Dust Sublimation	Unknown
1200K Lava Line	Unknown
320K Habitable Zone Start	Unknown
230K Habitable Zone End	Unknown
150K Frost Line	Unknown

The Sirius system comprises two distinct stars:

• Sirius A: The primary star, classified as A1V.
  • A: Indicates it is a hot, blue-white main-sequence star (surface temperature ~9,940 K).
  • 1: A sub-division indicating it's near the hotter end of the A-class spectrum.
  • V: The luminosity class signifies it is on the Main Sequence, fusing hydrogen into helium.

Sirius A is roughly twice as massive and 1.7 times the diameter of Sol, but about 25 times more luminous. Its brilliance in Earth's sky is due to both its intrinsic luminosity and its relative proximity.

• Sirius B: The companion star, classified as DA2.
  • D: Indicates it is a degenerate star, specifically a white dwarf. 'A' signifies a hydrogen-rich atmosphere, and '2' relates to its temperature (~25,200 K).
  • Sirius B is the remnant core of a once much larger star (estimated ~5 M☉) that evolved off the main sequence. Despite having a mass comparable to Sol (~1.02 M☉), it has collapsed to a size similar to Earth (~0.0084 R☉), making it incredibly dense. It is one of the most massive white dwarfs known and the closest one to Earth.

The two stars orbit their common centre of mass with a period of approximately 50 years, their separation varying between about 8 and 31 AU.

Role in Sirius System

Sirius A is the dominant gravitational anchor and energy source for the Sirius system. Its high luminosity creates a Habitable Zone much further out (~4.8 - 6.9 AU) and wider than Sol's. However, no planets have been confirmed orbiting either star in real-world observations. The evolution of Sirius B into a red giant and then a white dwarf would likely have significantly impacted any inner planets that might have formed earlier.

In-Game Representation

Sirius is included in Starship Simulator as part of the real-world star data integrated into the Galaxy Generation system (mentioned in Build 0.225.0.21 & 0.225.0.24), making it one of the "famous galactic neighbours" accessible to players.

• It can be targeted and scanned using the ship's Sensors.
• Its high luminosity may affect visual rendering and potentially sensor readings when nearby.
• Early development logs noted it might appear under the name "Dog Star" in some data lists.
• The presence and characteristics of any procedurally generated planets within the Sirius system in-game may differ from real-world data (or lack thereof).
• Both Sirius A and Sirius B are likely rendered as distinct stellar objects.