Reasons to Believe

How Far Tells How Old

The strength of cosmologists’ model for the origin and development of the universe rests in part on the certainty of astronomers’ distance measurements to stars and galaxies. The only direct measurements researchers have had for stellar distances are those based on trigonometry (specifically, a method called “trigonometric parallaxes”). Applying the ancient Greek theorem of plane geometry, the diameter of Earth’s orbit forms the base of a triangle. The sides of the triangle are the lines of sight from each end of that base (six month’s apart) to a particular star. Measuring the angles formed by those lines enables astronomers to calculate the distance to that star, the triangle’s vertex.

Because stars are so far away, the angles are nearly 90 degrees, so nearly that they are difficult to measure accurately. Until recently, this measuring technique could only demonstrate with certainty that starlight is more than 400 years old. Using “statistical parallaxes,” measuring trigonometric distances to say 10,000 stars all at roughly the same distance (as, for example, stars in globular clusters) astronomers extended their certainty to about 40,000 years.

With the help of the Very Long Baseline Array (VLBA), a string of radio telescopes stretching around the globe, astronomers have now measured the distance to the galaxy NGC4258, some 23.5 million light years away.1 Even since I began writing this article, the Astrophysical Journal published a report by two American astronomers who made a direct measurement of the distance to quasar 3C 279. It is 5.9 billion light years away, hence 5.9 billion years old.2 Details of the discovery and of its implications for divine design of the universe, as well as for settling disputes about the age of the universe, will be discussed by astronomers Rogier Windhorst and Kyle Cudworth in an upcoming issue of our new magazine, Facts for Faith.


  1. J. R. Hernstein, et al, “A Geometric Distance to the Galaxy NGC4258 from Orbital Motions in a Nuclear Gas Disk,” Nature, 400 (1999), 539-41.
  2. D. C. Homan and J. F. C. Wardle, “Direct Distance Measurements to Superluminal Radio Sources,” Astrophysical Journal, 535 (2000), 575-85.

Subjects: Astronomy and the Bible, Big Bang, Origin of the Universe, Scientific Evidence for an Old Earth, TCM - Cosmic Design, TCM - Origin of the Universe, Universe Design

Dr. Hugh Ross

Reasons to Believe emerged from my passion to research, develop, and proclaim the most powerful new reasons to believe in Christ as Creator, Lord, and Savior and to use those new reasons to reach people for Christ. Read more about Dr. Hugh Ross.