Does the sun have a proper name?
The Sun, the source of light and heat on Earth.
Photo:
NASA SOHO
See a larger version of this image.
Many stars in the night sky have names. The sun is a star. Doesn’t it have a name?
You’ve probably heard star names such as Polaris the North Star – or Betelgeuse in the constellation Orion. But, although it’s also a star, our sun doesn’t have a generally accepted and unique proper name.
You sometimes hear the name Sol in association with the sun. That’s the Roman equivalent of the Greek sun god Helios. But it’s not an official name for the sun.
So the sun doesn’t have its own name. But it does have a symbol that’s exclusively its own. The sun’s symbol is a circle with a dot in the center – used in mathematical formulas.
In being nameless, our sun has company. There are several thousand stars visible to the eye, and only a few hundred of them have names. Astronomers use the Greek alphabet to order visible stars in each constellation, according to their brightness. To identify stars invisible to the eye, astronomers turn to star catalogs, which assign a number to each star according to its position in the sky.
Could the Orion Nebula vanish in a few billion years? Could the same to the Milky Way?
Dan, I don’t know if there have been studies on how long the Orion Nebula will last. It’s a cloud of gas and dust in space. It’s a place where new stars are forming and its bright young stars are only millions of years old, in contrast to our sun, which is billions of years old. So it’s logical to imagine the Orion Nebula as a temporary feature … although a very long-lived feature, in human terms. Someday, there won’t be a nebula. There will just be the stars, made from the current nebula’s gas and dust. Of course, all of these processes are cyclical, with those stars evolving and sometimes releasing part of that material back into space again. But some of the material from the original nebula will eventually get locked up in stars, which will live out their millions- or billions-of-years livespans and then cease to shine.
The Milky Way galaxy is much, much longer lived. The Orion Nebula is a feature within the Milky Way galaxy, which contains stars, and other vast clouds of gas and dust like the Orion Nebula.
The Milky Way galaxy definitely won’t vanish in a few billion years. No one really knows its fate. If we live in a universe where the current expansion of the galaxies apart from one another someday reverses – if the galaxies someday begin moving back toward each other, so that the universe is collapsing, not expanding – well, that’s one fate. Another fate could be that the universe will expand endlessly, so that ultimately all (or most) of the matter in the galaxies gets locked up in dead or dying stars. In that scenario, the galaxy would still exist, but it would someday be totally dark, with no stars shining, and very isolated, with all the other galaxies still expanding away from each other …
Or something else could happen that we haven’t thought of yet … !
Deborah
When I was editing reports for the U.S. Global Change Research Program/Climate Change Science Program, the federal multiagency program that supports scientific research and global observing systems, we referred to the Sun and Earth, both capitalized, i.e., we treated them as proper nouns. In these U.S. Government publications, the name of the star at the center of our solar system is the Sun, and the name of our home planet is Earth. All stars are suns, but there is only one Sun.
Rick Piltz
Director, Climate Science Watch
Washington, DC
This NASA page says the sun doesn’t have a real name. http://solarsystem.nasa.gov/faq/index.cfm?Category=Sun
And it says the moon doesn’t either.
Well about the nebula,i’ve heard that when the nebula is dead, that once the stars will burn.When they burn,the stars all all gone.The gases will be left so the milky way’s place is still there,but later,they will be sucked up by gravity by galaxies we don’t know about.When that happens,what we think is a “black hole”
and will soon join that family.But if that black doesn’t happen,something will happen that scientists believe won’t happen.I’m Dan Keenan,I am ten years old.
If Pluto is not a planet does that mean the ones even further are’t planets either?
Hi Ryan, here’s the new definition of a planet from the International Astronomical Union. Here it is: “The IAU members gathered at the 2006 General Assembly agreed that a “planet” is defined as a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and© has cleared the neighbourhood around its orbit.”
With this definition, it doesn’t seem likely that any new planets will be found in our solar system. But lots of astronomers are already saying they intend to ignore the IAU’s new definition.
Also, astronomers are finding lots of extrasolar planets – planets in other solar systems.
Also, you might like this Pluto factsheet.
Eris is larger than Pluto—and much farther from the Sun than Pluto. Thus, if one accepts the common-sense idea that Pluto is a planet, then Eris is a planet, too.
Of course, common sense is in short supply these days, especially at the IAU.
The sun does have a name – Helios