If you watch the Big Bang Theory, then you probably have their theme song by Barenaked Ladies memorized. How does it go again?
Our whole universe was in a hot dense state, then nearly fourteen billion years ago expansion started, wait! No really, wait. The Universe is 14 billion years old?
Well, since 2003, NASA has claimed that they have accurately determined the age of the universe to be 13.7 billion years old. How have they come to this conclusion?
Constantly looking out into space, WMAP scans the cosmos with its ultra sensitive microwave receiver, mapping any small variations in the background “temperature” (anisotropy) of the universe. It can detect microwave radiation in the wavelength range of 3.3-13.6 mm (with a corresponding frequency of 90-22 GHz).
According to NASA, their WMAP (Wilkinson Microwave Anisotropy Probe) has allowed them to find the farthest object in the universe to be 13.7 billion light years away. Apparently, this means that the object we see today emitted it’s light 13.7 billion years ago. Hmm…. anyone else confused?
Okay, in simple terms, how exactly does NASA estimate the age of the universe?
Astronomers estimate the age of the universe in two ways:
1) by looking for the oldest stars
2) by measuring the rate of expansion of the universe aka “Hubble’s Constant”
1) How are we able to find the oldest star? ANSWER: The Hubble Space Telescope.
NASA tells us that HST’s lens is greater than any other telescope’s and can view exploding stars that are billions of light years away. Apparently, expansion increases with 70 km/second for every 3.26 million light-years you look further out into space.
The Hubble Space Telescope, a basic reflector with a 94.5-inch (2.4-meter) mirror, was packed with instruments that would give astronomers clear views of the universe in visible, infrared and ultraviolet light.2) Okay, this one makes no sense to me. How do we measure the rate of expansion?
2) How does NASA measure the rate of expansion of the universe?
- Hubble’s sharp vision means that it can see exploding stars, supernovae that are billions of light years away and difficult for other telescopes to study. A supernova image from the ground usually blends in with the image of its host galaxy. Hubble can distinguish the light from the two sources and thus measure the supernova directly.
- WMAP determines the density, composition and expansion rate of the universe by mapping the cosmic microwave background aka measuring the thermal radiation in space.
Let’s sum things up. The universe is precisely 13.7 billion years old, because:
1) We are able to measure the distance light has traveled from the farthest known star using the WMAP a radiation receiver that has the ability to scan billions of light-years into space. (FYI a light-year is about 6 trillion miles)
2) We are able to measure the rate of expansion by analyzing the aftermath of an exploded star aka a supernova. NASA uses the HST to measure the distance between 2 light sources a supernova’s and it’s host galaxy.
3) All I can say is… wtf is NASA talking about? I tried to read up on how the WMAP and HST can reach billions of light-years into space and information just isn’t there. As far as telemetry goes, I couldn’t find anything aside from what NASA considers as the “results.” Why hasn’t NASA better explained the mechanics of WMAP or the HST when this technology has been around for years?
Is there a way to explain NASA’s space technology to the masses? NASA has only been around for 50 years. It makes no sense to me that they have developed such astounding technology that can view and scan radiation that is 3.7 billion light-years away, when the moon is only 238,900 miles from Earth. If NASA can’t make another trip back to the moon, because it’s too difficult to reconstruct the vessel they destroyed, then how is it we’re constructing equipment that can accurately identify and study the oldest star in space? NASA, the moon is only a little more than a couple hundred thousand miles away. How is it we’re able to see the edge of the universe, but not go back to the moon?