Orion Nebula Gets New Milepost Marker, Now Closer

twilight30 writes "Discovery News is reporting that 'One of the most famous and scrutinized heavenly objects is 10 to 20 percent closer than we thought, say two teams of radio astronomers who have made some of the most precise cosmic distance measurements ever, with a telescope nearly as big as Earth. The Orion Nebula is the closest major stellar nursery to Earth, so it has been heavily studied to learn about the lives of stars. Its distance from Earth, however, has long been a matter of uncertainty, with an estimate made about 25 years ago in need of revision.'"

question:

[Anonymous Coward]

In the 6 months between measurements, the nebula didn't stay still (more precisely, our solar system is known to be rotating counter planar approximately 3 degrees). I assume they've accounted for the red/blue doppler shift, but if the Orion Nebula is undergoing rapid beta expansion, the measurements would be invalid. I don't know of any way to correct for this phenomenon...

Re:question:

[Anonymous Coward]

How could they not have realized that we've actually travelled in "Hypertime" and all their measurements from 25 years are all vaild ?
http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/10/10/scitime110.xml [telegraph.co.uk]

Re:"a telescope nearly as big as Earth"

[SnoopJeDi]

Not to mention if you consider that the awful comparison seems to suggest Gravitational Lensing [wikipedia.org].

Combine the measurements for increased accuracy

[SirBruce]

The old measurement was 1,565 +/- 266 LY.

Bower's new measurement is 1,270 +/- 76 LY.

Assuming both error bars are correct, then by combining the two measurements we get between 1,299 LY and 1,346 LY.

Reid's new measurement is 1,350 +/- 23 LY.

So combining again, we can conclude the Orion Nebula is between 1,327 and 1,346 LY away, or 1,336.5 LY +/- 9.5 LY.