HUBBLE’S LAW AND RED SHIFT
Hello all my fine friends! How have you been this week? We all here have been fine. The winter storms have passed by and once again I can see the stars shining bright at night.
And speaking of stars…I am going to continue with astronomy for the next several weeks. I’m sure most of you have heard of the space telescope Hubble launched into low earth orbit in 1990. It was named after American astronomer Edwin N. Hubbell. Less well known is the natural law named after this same man; Hubble’s Law. So what exactly is this law?
“Astronomers understand Hubble’s Law as being a result of the expansion of the universe. As the light waves travel, the space in which they are traveling is being stretched out; so, the wavelength of the light is increased. The longer the light has been traveling, the more its wavelength is increased. This is why more distant galaxies are much more redshifted than nearby ones.”1
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| Expanding universe. |
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| Depiction of red and blue shifted and stationary galaxies. |
“Edwin Hubble discovered the observed relationship between redshift of light and distance to a galaxy in the 1920s. His initial observations and the data he collected on galaxies were the first to establish that there are galaxies beyond the Milky Way galaxy. Then he went on to show that the brighter galaxies were not as red as the dimmer galaxies. He further determined that the brighter galaxies were closer to Earth than the dimmer galaxies that contained greater redshifted spectral lines.”2 And this, in a nutshell, is Hubble’s Law.
Other methods are used as well as a check and balance for the accuracy of each other. For example, another method utilized in trying to determined distant planet movement is the Doppler Effect. Perhaps you are most familiar with this in sound waves. We can hear a car, train, plane or even someone panting as they are coming toward us. But as they come even with us and then move away from us the sound changes. This is due to the sound waves spreading out and therefore the pitch of the sound goes down as the object leaves us.
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| Doppler effect. |
“The Doppler Effect is something that happens to waves when the source of the waves is moving (such as when a star moves away from Earth). Note that Hubble’s Law is not due to the Doppler Effect but there is a Doppler Effect on the light from stars and galaxies. For the very largest distance scales, the Doppler Effect would be much smaller than the redshift effect from the expansion of space…Light is affected the same way if a star is moving away from Earth. Thus, a star moving away from Earth causes the frequency or color of the light to shift toward the red—or down in frequency. If a star is moving toward Earth, its frequency is shifted higher, toward the blue end of the spectrum. Within our own galaxy, about half of the stars are shifted toward the blue, and half are shifted toward the red. We know the light is shifted because we can compare the light spectrum from objects in space to the light emitted by known substances in a laboratory.
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| Stars can be red/blue shifted or they can get their coloring from the gases that are burning. |
“Almost all galaxies are shifted toward the red. Furthermore, the larger the redshift, the greater the object's distance from us. This is exactly what we would expect if the entire universe is expanding, and the light is redshifted as a result of that expansion.”3
And as creation scientists we know from God’s word that the
universe is expanding as recorded in Psalm 104:2 “Who coverest thyself with light as with a garment: Who stretchest out the heavens like a curtain.”
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| Don’t get the blue stars mixed up with blue galaxies. This is an actual photo of the most distant galaxy known. Note the brilliant red coloring. |
But what about the evolutionist? Can red shift and Hubble’s Law be used to explain the big bang theory?
Stay tuned for next week and find out!
Until then, God bless and take care,
Willow Dressel
This week in the night skies; for the northern lats; “Monday, January 26
Earth to dodge a bullet! A relatively large near-Earth asteroid, 2004 BL86, is flying by our planet, passing us by three times the distance of the Moon. Tonight the asteroid will brighten to 9th magnitude as it crosses Cancer, nicely placed in the evening hours for telescope users in the Americas. See the article and detailed finder chart in the February Sky & Telescope, page 50, or our version online: Mountain-size Asteroid Glides Past Earth.”4
“Same for the southern lats; Near Earth Asteroid 2004 BL68 will come close to Earth on 16:20 UT 26 January at distance of 0.008 AU (around 3.1 Earth-Moon distances). It is brightest at 04:00 UT on the 27th though. It has an estimated diameter of 680m (a bit over half a kilometer). The asteroid will be a reasonably bright magnitude 9.0 at closest approach, and it comes close to the iconic Beehive cluster when it is still bright. The flyby of 2004 BL86 will be the closest by any known asteroid of this size until 2027 when asteroid 1999 AN10 goes past Earth. It is also the brightest since 2012 DA14 in 2013. Unfortunately, from Australia the asteroid is below the horizon at its brightest. We get to see it when it is between magnitudes 10-9.6. The theshold for unaided eye viewing is magnitude 6, so the asteroid is quite dim. Australians can see the asteroid move from Puppis (on the late evening of the 26th, Australia day) through Monocerous and into Hydras. While the asteroid can be picked up by high end binoculars under dark sky conditions, for most observers small telescopes will be required.”5
References:
2Dobberpuhl, Delmar, The First Four Days, WinePress Publishing, Enumclaw, WA. 2011. Pp. 158-9.
5http://astroblogger.blogspot.comCreation The Written Truth
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