Subject: Re: Open time still available 31 Dec.

From: Neil de Grasse Tyson

Submitted: Wed, 29 Dec 1999 20:14:35 -0500

Message number: 410 (previous: 409, next: 411 up: Index)

Dear Bruce & Ed,

Assuming that a night assistant can collect all images without my 
participation, I would like to apply for **all** of the time on New 
Year's eve, for a two purposes:

1) To image a dozen, or so, objects (mostly QSOs) that have at one 
time or another held the record for the most distant object known. 
(The total number is only 24 that have ever held the record -- all 
the way back to the Andromeda Galaxy, in 1926)


We would use this image album for exhibitry in our new Hall of the 
Universe of the American Museum of Natural History. In particular, we 
have already created a 100-meter long, 300-image timeline of the 
13-billion year history universe, with images of objects from every 
redshift from 0 --> 5.6.

The record holders form a subset of these 300 images.  The images we 
currently have for most of this group are poor, and are, for the most 
part, taken from the POSS-I plates.  I would like to replace as many 
as possible with a "fresh" set, that goes deeper, to especially 
reveal assorted extended objects in the image.

Individual exposures needn't be long -- and multiple exposures are 
not necessary. For 20th magnitude QSOs, perhaps 5-10 minutes each?  I 
may want three bands just to create a color image.  Remember, these 
will primarily be used for display.

APO will be duly credited as the telescope on each image displayed. 
And I may even write an educational book that chronicles the 
astrophysical search for record holders.

Coordinate list will follow if I am awarded time.


2) Three+ hours of H-alpha exposure of a dwarf nova in collaboration 
with Mike Shara, here in the Department of Astrophysics as the 
Museum. (More specifically: we would image for all the the remaining 
time after the above project.)


There must be condensed ejecta around dwarf novae because we see 
their barely escape-velocity winds (P Cygni profiles) in HST spectra. 
We have no idea if jets, blobs or a uniform wind is ejected, or how, 
or why. A summed image of several hours from a 3.5 m scope would 
likely show, for the first time,
the ejecta and its symmetry. The FOV is just right, And it's at the 
right hour angle for this time of year at APO.

U Geminorum (prototype dwarf nova)
alpha(2000) = 07h55m05.3s
delta(2000) = +22deg 00' 05"
Halpha filter

Width preferred is 50 Angstroms, but 25-100 Angstroms are all OK.

Eighteen + images  in Halpha (10 min exposure each)
offset from each other by a few (3-5) arcseconds each time.

Also: 5 images, 2 minutes each, in broadband R filter, offset from 
each other by a few arcsec (3-5) each time.


Thank you.

I look forward to hearing from you.


p.s.  I cannot "drive" the telescope that night because I am 
scheduled to fund-raise at a big shin-dig here in NYC appear live on 
Peter Jenning and Tom Brokaw.

-Neil deGrasse Tyson
Department of Astrophysics & Director, Hayden Planetarium
American Museum of Natural History
Visiting Research Scientist & Lecturer
Department of Astrophysical Sciences, Princeton University


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