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Star profile

Mothallah

Alpha Triangulum · Triangulum

Variable star
3D likeness based on its real data · class F · ~6,500 K

What is Mothallah

Mothallah is the alpha of Triangulum, one of the smallest and most ancient constellations, already catalogued by Ptolemy in the second century. Its Arabic name, «Al-Muthallath», simply means «the triangle», naming both the figure and its leading star. At 63 light-years, it is a gentle F-type variable: a yellow-white flame whose brightness shifts almost imperceptibly. In the same patch of sky lies an entire spiral galaxy, M33, neighbour of Andromeda and silent witness to the flow of cosmic time.

Where it is and when to see it

Mothallah lies in the northern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is October, when it culminates around midnight.

  • From London it culminates about 68° above the horizon.
  • From New York it culminates about 79° above the horizon.
  • From Sydney it culminates about 27° above the horizon.

It can be seen from anywhere north of 60° S.

It ranks no. 2 in brightness among the 18 stars of Triangulum in our catalogue. To find it, start from Beta Triangulum, the brightest: it lies about 6° away (a fist at arm's length covers about 10°).

The light you see today left it about 63 years ago.

Find it on the sky map

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Leave your signature on Mothallah

Your name and a message go up on the map for everyone to read. Signing is free.

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A public signature from a real person. The chosen name is a symbolic denomination within Stelvia, with no official standing or IAU recognition: the sky is not for sale and belongs to no one.

Astronomical data for Mothallah

Constellation
Triangulum
Apparent magnitude
3.42
Distance
63.3 light years
Coordinates (J2000)
RA 28.270° · Dec 29.579°
Catalogue
HIP 8796 · HD 11443

A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.

Other stars in Triangulum

Triangulum has 18 stars in Stelvia's catalogue. Here are a few of them.

See all 18 stars in Triangulum