Names?

[Danzi]

I am a bit confused, i know that planets names are taken from mythology, but where do their alternative names come from and mean. I am refering to the names such as
2003 UB 313 - which is Eris
and
2005 FY9

I realise the 1st bit is the date they are discovered, but what doe the rest of the numbers and letters mean?

 

[MeteorWayne]

These are the preliminary designations. The year of course comes first. The first letter refers to what 2 week period of the year the discovery was made. Jan 1-15 is A, Jan 16-31 is B and so on. (I and Z are not used) The second letter is the order of discovery during that 2 week period, I is not used. After the first 25, then a number is added and the letters are assigned in order. after the next 25, the number goes from 1 to 2, then it's A to Z again.

For example, a very good month...2006 SF 281...was the 7056 asteroid discovered that half month!!

For more detail, read this:
(copied below)

http://www.cfa.harvard.edu/iau/info/OldDesDoc.html

New-Style Provisional Designations
The Minor Planet Center assigns new provisonal designations when it is in possession of at least two nights of observations of an object that cannot be identified immediately with some already designated object.
The standard designation consists of the following parts, all of which are related to the date of discovery of the object: a 4-digit number indicating the year; a space; a letter to show the half-month; another letter to show the order within the half-month; and an optional number to indicate the number of times the second letter has been repeated in that half-month period.

The half-month of discovery is indicated using the following scheme:

Letter Dates Letter Dates
A Jan. 1-15 B Jan. 16-31
C Feb. 1-15 D Feb. 16-29
E Mar. 1-15 F Mar. 16-31
G Apr. 1-15 H Apr. 16-30
J May 1-15 K May 16-31
L June 1-15 M June 16-30
N July 1-15 O July 16-31
P Aug. 1-15 Q Aug. 16-31
R Sept.1-15 S Sept.16-30
T Oct. 1-15 U Oct. 16-31
V Nov. 1-15 W Nov. 16-30
X Dec. 1-15 Y Dec. 16-31

I is omitted and Z is unused

The order within the month is indicated using letters as follows:
A = 1st B = 2nd C = 3rd D = 4th E = 5th
F = 6th G = 7th H = 8th J = 9th K = 10th
L = 11th M = 12th N = 13th O = 14th P = 15th
Q = 16th R = 17th S = 18th T = 19th U = 20th
V = 21st W = 22nd X = 23rd Y = 24th Z = 25th

I is omitted

If there are more than 25 discoveries in any one half-month period, the second letter is recycled and a numeral `1' is added to the end of the designation. If more than 50 discoveries, the second-letter is again recycled, with a numeral `2' appended after the second letter. Discoveries 76-100 have numeral `3' added, numbers 101-125 numeral `4', etc. When possible, these additional numbers should be indicated using subscript characters.
Thus the order of assignment of designations in a particular half-month period is as follows: 1995 SA, 1995 SB, ..., 1995 SY, 1995 SZ, 1995 SA1, ..., 1995 SZ1, 1995 SA2, ..., 1995 SZ9, 1995 SA10, etc.

This scheme has been extended to pre-1925 discoveries--such designations are indicated by the replacement of the initial digit of the year by the letter `A'. Thus, A904 OA is the first object designated that was discovered in the second half of July 1904.



MW

 

[Danzi]

Ok, i just want to check this then

Lets use Makemake
Its 2005 FY9

This means - discovered 2005, the F means it was the second half of march. and the Y9 would mean that its the 24th to be discovered during the 9th set of 25 discoveries?

I hope thats right, the second letter and last number is still confusing me, so i hope that im right for the makemake example!

 

[MeteorWayne]

Ok, i just want to check this then

Lets use Makemake
Its 2005 FY9

This means - discovered 2005, the F means it was the second half of march. and the Y9 would mean that its the 24th to be discovered during the 9th set of 25 discoveries?

I hope thats right, the second letter and last number is still confusing me, so i hope that im right for the makemake example!

You got it!

 

[eosophobiac]

This is an interesting thread.
I understand up to the point of the letters: using ex 2003 UB 313, I understand Eris was discovered in 2003, half month of 16-31 Oct, and the order within the half month is 2nd... Correct? But then get lost trying to interpret the final set of numbers - the '313'. Does it mean the order within the half month was repeated 313 times? Or was the order repeated 3 times, plus another 13?

I feel like a geek, but then I think, "a geek would understand this better than I*!"
:geek:

[*no slight intended to any 'geeks'.......]

 

[MeteorWayne]

Yep it was 313 times. So UB 313 means it was the 7827th asteroid discovered during that half month. Amazing, eh?

 

[eosophobiac]

Thanks, MW! That is a lot of discoveries!

 

[MeteorWayne]

It sure is! That was about the time when the Catalina survey came online, so I suspect that had something to do with the spike in late 2003.

 

[Danzi]

Thanks, this all makes sence when you know how

I impressed a lot of people today using this - as none of them knew it before.

Thanks