Wayne Pryor
<- Recent Book with UVIS cover art

• Katerina Radioti et al.: Bifurcations of the main auroral ring at Saturn: ionospheric signatures of consecutive reconnection events at the magnetopause, submitted to JGR
• Denis Grodent et al.: Small scale structures in Saturn’s auroras, accepted to JGR .
• Pryor, Rymer et al.: The auroral footprint of Enceladus, published in Nature
• Henrik Melin et al.: Simultaneous Cassini VIMS and UVIS observations of
Saturn’s southern aurora—comparing emissions from H, H high spatial resolution, submitted to GRL .
2
, and H
3
+ at a
• Laurent Lamy et al.: - Multi-instrument radio/UV/IR/and ENA simultaneous observations of Saturnʼsaurorae- pending

Lamy comparisons: 2009-027

Nature Paper on Enceladus Footprint: is out!
Noon
-movie shows 5 sequential EUV frames; frames 2, 3, 4 show N footprint where predicted
-figure on the right was suggested as cover art

Auroral PDF “book” just updated this weekauroral images + geometry overlay
• Now covers ODCID-1143 images from 2006-
2011
• Includes 2 recent Hubble campaigns from
Spring 2011

Cassini Planning- Inclination Plot

UVIS Planning Report for XXM (Solstice Mission, now to 2017)
Alain Jouchoux, UVIS team, is implementing
2 kinds of ORS campaigns with UVIS prime:
AURSTARE: High Phase Angle , mix of UVIS imaging slews and stares for
ISS/VIMS night-side imaging
ISS needs 100-140 degrees phase for auroral imaging
Typical UVIS slew rate is 0.06 mrad/s, 8 s integrations
AURSLEW: Low Phase Angle , mix of UVIS imaging slews and stares for
VIMS dayside auroral imaging.
These are being coordinated with Kevin Baines and Ulyana Dyudina

AURSTARE
• 50% UVIS slewing (slit N-S or E-W), imaging nightside
• 50% UVIS staring at dark limb at 75 N or S for ISS imaging
(sample movie with grid lines at 74 and 78N below)
• ISS wants stars in FOV for limb altitude determination

• Two types:
• NORMAL: 50/50 mix by time of fast slews for
UVIS (60 microradians/s) imaging and stares for VIMS imaging
• SLOW: 7 microradians/s slews for joint simultaneous UVIS/VIMS imaging (new thing!)

• Poster at MOP on ISS-UVIS comparisons
• Work up HST campaign periods (one period will be shown next)
• Jacques Gustin will work on this too

Nichols
HST
Campaign
April 2011
UVIS
UVIS views N, repeatedly scans across oval, upper envelope of points shows the brightest pixels as a function of time
In the following slides, all are scaled the same way so colors can be compared.

Day 90

Day 99

Bright rotates day to night……
Day side Night side

Now go to “book” start at page 175 or so…

• ISS movie from Ulyana Dyudina

October 2009 ISS observation
Ulyana Dyudina, Andy Ingersoll
Day side stars
• 472 frames
• 81 hour
• 2 - 3 minute exposures
• Broadband visible wavelengths, no color information
• Orange aurora is a false color

October 2009 movie (472 frames, 81 hours)

stars minutes for bright features like
“Snake”
• “Snake”-like features appear just twice in 81 hours.
• Curtains reappear on consecutive Saturn days

curtain
• Image scale is 32 km (20 miles) per pixel stars
• Curtain height is 1,200 kilometers (746 miles) above the planet's limb.
• Latitude of aurora is about
74° and changes with time by several degrees.

During ISS movie..
Dawn
Dawn
Dawn
Dawn Planetary
Rotation
Dusk
Dusk
Dusk
Dusk rotation
Time->
Stationary UVIS slit aligned E-W on Saturn North
Time marches to right.
Diagonal formed from bright spots
(Something bouncing back and forth as Saturn rotates?)
Period like an hour: too long for mirroring electrons. (Slide notes).
Alfven waves bouncing back and forth? Mirroring ions?
V alfven
= B/sqrt(
0 n i m i
) in SI

Same UVIS data plotted by Greg
Holsclaw:

Night-side, slit aligned E-W, quasi-periodic bursts seen.
Feature rotates, with general brightening over growing local time range

bright continuous diagonal

Case that goes with ISS snake
ISS snake at 280T23:00

Last one so far- weak episodic diagonal

Gerard HST STIS FUV campaign coordination
• 2 HST orbits starting w/ 2011-Jan-28 13:00-14:00
• (2011-day 28, spectra were geocorona only)
• (reschedule/rerun on March 17- L spectra were ok)
• 2 HST orbits starting w/ 2011-Apr-17 21:30-22:30
• (2011-day 107)
• 2 HST orbits starting w/ 2011-May-10 12:25-13:30
• (2011-day 130)

2011-Jan 28 HST
• HST program 10235: Jean-Claude Gerard, PI
• Jan 28 2011 (day 28) pointing problem, images, no spectra
• Hello, 
 The first visit (2 orbits) of our HST program 
 12235 (FUV spectroscopy of Saturn's aurora) took 
 place on January 28th, with concurrent UVIS 
 observations from Cassini. Images were 
 successfully taken at the beginning of both 
 orbits (see appended files) and show a reasonably 
 bright aurora.
Following the image, long time-tagged spectra 
 should have been taken for which the phase 2 
 proposal requested pointing at 50° N, followed by 
 a 3 arcsec slow slew towards the north to scan 
 the auroral region.
However, the G140L and the
G140M spectra show no 
 emission feature at all, suggesting that the 
 pointing of the STIS slit missed the planetary 
 disk and only observed the dark space. The 
 headers indicate that the initial slit position
before the slew started was already 2°-3° off the 
 disk. Since the slit was moved northward, further 
 away from the planet, it never hit the aurora nor 
 the disk. 
 Consequently, no aurora, airglow nor reflected 
 solar radiation was observed, neither in the 
 G140M nor in the G140L modes. Only geocoronal 
 Ly-alpha and OI1304-A terrestrial airglow were 
 detected (see enclosed files). 
 I sent a request to STScI for an
HOPR to repeat 
 the observations. It has now been approved and 
 the observations will be repeated as soon as 
 possible, this time without parallel Cassini 
 observations. The cause of the too large offset 
 from the planet's center applied to the telecope 
 is linked to an inadequate update of the 
 observing date in the observation planning 
 software when using the slew mode of HST. This 
 was only the 3rd times this mode was used since 
 HST started its operations !
I shall keep you informed when further news are available.
Cheers, 


 Jean-Claude.

UVIS geometry for HST period in 144:
• 2011-028T10:00:00 to 2011-028T21:00:00
UVIS_144SA_AURSTARE001_PRIME
• Phase: 121.1-125.0 degrees
• Range to center: 26.07-23.30 Rs

Notes from Alain Jouchoux on
UVIS_144SA_AURSTARE001_PRIME: 
 - Used the south pole to allow ISS to be in the dark.
- The total number of scans is 22
• UVIS scan start and end
ISS stare position

• obhu21btq_flt_prev_1.png

UVIS geometry for HST period in 147:
• 2011-107T12:28:00 to 2011-107T23:08:00
UVIS_147SA_AURORA001_PRIME
• Phase: 69.4-10.9 degrees
• Range to center: 5.01-9.01 Rs

• Wayne, 

 The pointing design for UVIS_147SA_AURORA001_PRIME is a 
 little tricky: (1) the UVIS slit is almost parallel to 
 the equator, so we have to scan South/North; and (2) the 
 apparent size of
Saturn is much larger that the slit length 
 (402 mrad at the start of the request and 222 mrad at the 
 end.) That forces us to do 5 South/North scans separated by 
 30 mrad (VIMS FOV is 32 mrad) to cover the full oval at the 
 north pole. So we end up doing only (?) 3 coverages of the 
 full oval.
Attached are 6 images showing the starting and ending position 
 of each 5 individual scans for each of the 3 full oval scans.
The scan rate is 0.007 mrad/s and the separation between 
 each individual scan is 30 mrad.
So: (1) Is that what you want?; (2) The scan moves following 
 Saturn rotation. Is that Ok? and (3) North pole or South Pole?
(I did not see if Jean Claude answer. I assume that observing from 
 Earth orbit he wants the North pole).
Alain

Start (top) and end (bottom) positions for the
5 scans of the first polar image

Start (top) and end (bottom) positions for the
5 scans of the
2nd polar image

Start (top) and end (bottom) positions for the
5 scans of the
3rd polar image

Sample UVIS
Data 2011 Day 107

UVIS geometry for HST period in 148
• 2011-130T11:12:00 to 2011-130T13:40:00
UVIS_148SA_AURSTARE002_PRIME
• Phase: 170.4-165.5 degrees (night side)
• Range to center: 7.87-7.08 Rs

• This year we are emphasizing collaborative datataking and then papers:
– ISS/UVIS (correlate events)
– UVIS/VIMS (are the images fundamentally different?)
– STIS/UVIS (complementary spectroscopy/imaging)

In 141:
• 2010-330T22:30:00 2010-331T09:30:00 d a .
UVIS_141SA_AURSTARE001_PRIME
• Phase 117.9-120.7 degrees
• Range to center 30.08-27.76 Rs

In 142
• 2010-353T02:00:00 2010-353T13:00:00 d a .
UVIS_142SA_AURSTARE001_PRIME
• Phase: 130.4-137.0 degrees
• Range to center: 20.76-17.26 Rs

Also in 142
• 2010-357T03:30:00 2010-357T13:30:00 d a .
UVIS_142SA_AURSLEW001_PRIME
• Phase: 60.9-64.6 degrees
• Range to center: 23.01- 25.59 Rs

• 2011-009T13:06:00 2011-009T22:31:00 d a .
UVIS_143SA_EUVFUV001_PIE
• 2011-010T10:21:00 2011-010T14:49:00 d a .
UVIS_143SA_EUVFUV002_PIE

Also in 144:
• 2011-033T08:24:00 2011-034T02:46:00 d a .
UVIS_144SA_AURSLEW001_PRIME
• Phase: 60.5-66.6 degrees
• Range to center: 23.22-27.70 Rs

Also in 144:
• 2011-034T03:50:00 2011-034T20:34:00 d a .
UVIS_144SA_AURSLEW002_PRIME
• Phase: 66.9-71.1 degrees
• Range to center: 27.93-31.31 Rs

• 2011-052T16:30:00 2011-052T21:31:00 d a
.
UVIS_145SA_EUVFUV001_PIE
• 2011-053T10:11:00 2011-053T20:36:00 d a
.
UVIS_145SA_EUVFUV002_PRIME
• 2011-058T08:12:00 2011-058T18:52:00 d a
.
UVIS_145SA_EUVFUV003_PRIME
• 2011-061T13:57:00 2011-062T03:37:00 d a
.
UVIS_145SA_EUVFUV004_PRIME
• 2011-063T13:27:00 2011-064T02:07:00 d a
.
UVIS_145SA_EUVFUV005_PRIME

• 2011-078T14:45:00 2011-078T17:45:00 d a .
UVIS_146SA_EUVFUV001_PIE
• 2011-080T11:52:59 2011-080T18:53:00 d a .
UVIS_146SA_EUVFUV002_PIE

Also in 146:
• 2011-081T04:33:00 2011-081T15:33:00 d a .
UVIS_146SA_AURSLEW001_PRIME
• Phase: 33.7-40.2 degrees
• Range to center: 19.17-22.67 Rs

• 2011-105T06:00:00 2011-105T17:00:00 d a .
UVIS_147SA_AURSTARE001_PRIME
• Phase: 123.6-129.8 degrees
• Range to center: 22.67-19.30 Rs

Also in 147:
• 2011-111T10:03:00 2011-111T21:03:00 a .
UVIS_147SA_AURSLEW001_PRIME
• Phase: 52.7-54.9 degrees
• Range to center: 32.87- 34.84 Rs

In 148:
• 2011-127T01:17:00 2011-127T23:17:00 a .
UVIS_148SA_AURSTARE001_PRIME
• Phase: 101.1-107.0 degrees
• Range to center: 31.89- 27.14 Rs

• 2011-167T05:58:00 2011-167T20:57:00 a .
UVIS_149SA_AURSTARE001_PRIME
• Phase: 105.6- 112.5 degrees
• Range to center: 26.61-22.32 Rs

Also in 149:
• 2011-173T07:42:00 2011-173T18:42:00 a .
UVIS_149SA_AURSLEW001_PRIME
• Phase: 20.3-22.8 degrees
• Range to center: 29.25-31.44 Rs

In 150:
• 2011-189T14:54:00 2011-190T01:54:00 a .
UVIS_150SA_AURSLEW001_PRIME
• Phase: 82.6-88.9 degrees
• Range to center: 21.77- 18.43 Rs

In 151:
• 2011-210T07:07:00 2011-210T18:07:00 a .
UVIS_151SA_AURSLEW001_PRIME
• Phase: 73.1-76.7 degrees
• Range to center: 27.80-25.22 Rs

• 2011-237T01:34:00 2011-237T12:34:00 a .
UVIS_152SA_AURSLEW001_PRIME
• Phase: 11.4-13.8 degrees
• Range to center: 20.76-23.83 Rs

In 153:
• 2011-253T10:47:00 2011-253T21:47:00 a .
UVIS_153SA_AURSLEW001_PRIME
• Phase: 69.2-72.1 degrees
• Range to center: 30.31-27.99 Rs

• 2011-256T12:00:00 2011-256T18:00:00 d a .
UVIS_153SA_ENAURFOOT001_PRIME
• Phase: 121.9-152.7 degrees
• Range to center: 7.97-4.89 Rs

• 2011-273T03:17:00 2011-273T14:17:00 a .
UVIS_154SA_AURSLEW001_PRIME
• Phase: 86.9-95.2 degrees
• Range to center: 18.47-14.69 Rs

In 155:
• 2011-290T14:46:00 2011-291T05:46:00 a .
UVIS_155SA_AURSLEW001_PRIME
• Phase 82.4-91.5 degrees
• Range to Center 20.88-16.15 Rs

In 156
• 2011-309T01:17:00 2011-309T12:17:00 a .
UVIS_156SA_AURSLEW001_PRIME
• Phase: 91.2-102.9 degrees
• Range to center: 16.17-11.94 Rs

Also in 156:
• 2011-312T03:32:00 2011-312T14:32:00 a .
UVIS_156SA_AURSLEW002_PRIME
• Phase: 18.6-22.5 degrees
• Range to center: 20.29-23.30 Rs

In 157:
• 2011-327T07:02:00 2011-327T20:24:00 a .
UVIS_157SA_AURSTARE001_PRIME
• Phase: 100.1- 132.4 degrees
• Range to center: 12.69-6.49 Rs

Also in 157:
• 2011-329T12:33:00 2011-329T23:33:00 a .
UVIS_157SA_AURSLEW002_PRIME
• Phase: 6.89-18.3 degrees
• Range to center: 16.65-20.15 Rs

• 2011-345T13:35:00 2011-345T21:45:00
.
UVIS_158SA_ENAURFOOT001_PRIME
• Phase: 116.3 to 157.5
• Range to center: 8.66-3.51 Rs a