Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Closest Star
Name: discoverer
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 - 2000


Question:
What is the closest star to the sun. Some sources say Alpha Centauri and others say Proxima Centauri is the closest. Both are reliable is the closest star???


Replies:
The name "Alpha Centauri" actually denotes a triple star system in the constellation Centaurus (it appears as a single star to the naked eye). Two of these stars, denoted Alpha Centauri A and B, are very similar to the Sun and are approximately 4.336 light-years away. They orbit each other (better said, they orbit their common center of mass) with a period of about 80 years. Then, orbiting this pair is a small, faint star only a tenth the size of the Sun. This star takes one-and-a-half million years to orbit the larger pair; at the moment it is closer to us than the other two, a mere 4.205 light-years away. Because it is the nearest star to the Sun, it is named Proxima (from the Latin word for "nearest") Centauri. This information came from "Astronomy: The Cosmic Journey", an astronomy text by William Hartmann. I did not know this stuff myself 'til now!

Ron Winther



Click here to return to the Astronomy Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory