Betelgeuse! Betelgeuse! Betelgeuse! Quiz

Answer: In the shoulders

If Orion were a living person and facing us head-on, Betelgeuse would appear about where his right shoulder would be. The important point in the question is "from the perspective of an observer on earth". The stars are not actually lined up that way when observed from another perspective, lying between 243 and 1360 light years away from Earth. Because of its association with Orion, Betelgeuse is sometimes referred to as Alpha Orionis. When translated from the Arabic, Betelgeuse means "the armpit of Orion" or "the hand of Orion".

The diagram shows the constellation Orion with very little in the way of the head.

Answer: 1000-1 BCE

The first century CE Greek astronomer Ptolemy observed Betelgeuse describing its redness. Roughly three centuries before that Chinese astronomers described Betelgeuse, indicating it had a more yellowish hue. This difference suggests that Betelgeuse may be relatively young, as stars go. These astronomers even used Betelgeuse as an example of a yellow star in descriptions of various types of stars. This suggests that during this time Betelgeuse may have evolved from a hydrogen-burning star in the main sequence to a red gas giant.

The picture shows a heart with the name Johnny. Johnny Hart was the cartoonist who created the comic strip "B.C."

Answer: Its diameter is more than twenty times the Sun's diameter.

It is hard to get an exact measurement of Betelgeuse's diameter but studies suggest a range of 1.2 to 8.9 Astronomical Units (AU). The AU is equivalent to the average distance between the Earth and the Sun, about 149,600,000 kilometers. The distance between the Sun and Mars is about 1.5 AU. Ceres (in the Asteroid Belt) is about 2.7 AU. Jupiter is about 5.5 AU. Saturn is relatively not far beyond the range at 9.5 AU.

The Sun has a diameter of about 1,392,000 kilometers. Even the most conservative answer for Betelgeuse would lead to a diameter of about 179,500,000 kilometers, more than 100 times larger.

The diagram shows a set of colored circles with the red circle the largest, suggesting that the correct answer was the largest.

Answer: Betelgeuse is about ten times as massive as the Sun.

The mass of the Sun is about 2X10 to the 30th power kilograms. The estimated range for Betelgeuse is about 9.5 to 21 times the mass of the Sun. Some scientists believe that Betelgeuse had more mass earlier in its lifespan.

The picture shows two cubes. One is about ten times as large as the other in each dimension. One dimension has an arrow pointing to it and the other two dimensions have "X"s.

Answer: Betelgeuse's surface temperature is less than two-thirds of the Sun.

The surface temperature of the Sun is about 5,778 degrees Kelvin. By comparison, the surface temperature of Betelgeuse is about 3,500 degrees Kelvin.

The picture shows a thermometer reading a lower temperature, suggesting that Betelgeuse is cooler than the sun.

Answer: Mid-September to Mid-March

The main exception to this would be Antarctica south of 82 degrees South Latitude. The best time of the year to view Betelgeuse is mid-December. Along with Sirius and Procyon, Betelgeuse is part of the Winter Triangle in the nighttime sky.

The picture shows images of a jack-o-lantern (Halloween--October), a Christmas tree (December), and a heart (Valentine's Day--February).

Answer: 640 light years

More specifically Betelgeuse is about 642.5 light years from the sun. The light-year is about 9,460,000,000,000 kilometers. Astronomers use the minute movement that Betelgeuse and other stars make in the sky as the Earth orbits around the Sun to estimate the distance of these stars.

The picture shows a group of stars arranged in an eight-by-eight pattern. The stars total 64 and might suggest 640 light years.

Answer: Less than one billion years old

Betelgeuse is far less than one billion years old with common estimates suggesting that it is about ten million years old. Betelgeuse's large size and high level of consumption of its hydrogen will lead to it having a much shorter lifespan than smaller stars such as the Sun. It has been suggested that Betelgeuse's lifespan may end in another million years.

The picture shows a set of numbers with the one being the largest and in red (such as the red gas giant Betelgeuse).

Answer: About five km/sec

By comparison, Antares, another red supergiant, rotates at about 20 km/sec. It is estimated that it takes Betelgeuse about 8.4 years to do a complete rotation about its axis. Some scientists have even suggested that Betelgeuse does not rotate.

This picture shows two hands doing a "high-five".

Answer: It will become a neutron star

As Betelgeuse ages, it will shift from burning hydrogen, to burning first helium, and then heavier elements, ending with iron. Betelgeuse will likely become a neutron star, as is common among stars with masses between 10 and 29 times that of the sun. Neutron stars are much smaller than red supergiants or even average sized stars such as the Sun. A typical sized neutron star has a radius of about 10 kilometers. A neutron star does not usually generate additional heat and will cool over time.

The picture shows a circle with an absence of color (other than the border), hopefully leading you away from the "color" choices to the correct answer.