SERENA Meeting Visby 2010 Na EXOSPHERE GROUND--BASED GROUND OBSERVATIONS: past and future Valeria Mangano Interplanetary Space Physics Institute (IFSI) Roma, Italy
Outline Italian campaign at TNG in 2002-2009 French-Italian campaign at THEMIS in 2007-2010 IMW coordinated observations in 2006-2010 What s next?
TNG Alt-Az night telescope Primary Mirror 3.58 m Altitude 2387 m a.s.l. Lat. 28º 45 28 N Long. 17º 53 38 W SARG Echelle spectrograph Nasmyth telescope focus B Resolution: 46000-164000 (in our case 115000) Na filter 60 Ǻ (no order overlapping) Long slit (26.7 x 0.4 ) CCD dimension 2 K x 4 K pixels Telescopio Nazionale Galileo Roque de Los Muchachos, La Palma
THEMIS 0.90 m Solar Telescop Telescope e F/16 Ritchey Ritchey--Chretien telescope in alt alt--az mounting Helium filled telescope tube MTR mode for multiline spectropolarimetry Spectral range 400 to 1000 nm at : R ~ 220,000 Slit: 0.5" & 120 " long R ~ 400,000 Slit: 0.25" & 70 " long (low and high resolution) Four years of campaign (2007(2007-2010) 96 days of observation Spectral resolution 0.027 Å to 0.016 Å Spectral dispersion 10.2 to 6 må Two individual cameras: D1 Na at 5896 Å D2 Na at 5889 Å THEMIS Observatorio del Teide, Tenerife Latitude: Longitude: Elevation: N 28 18' 12.42" W 16 30 32.04" 2429 m
TNG Mercury Dataset: August 2002: 3 nights August 2003: 3 nights June-July 2005: 3 nights June 2006: 4 nights April 2009: 4 nights
TNG: observation on June-JulyJuly 2005 (at about 19:00 UT, for 1 h) Sun-Mercury Distance 0.422-0.423 AU Illuminated fraction 57-54 % Angular Diameter 6.7-7.0 Apparent Magnitude 0.05-0.15 Elongation (East) 24.2-24.9º True Anomaly Angle 124-130º Sun-Mercury-Earth phase angle 81-85º Exposure time: 120 Scan in the N-S direction: equator ± 6
TNG 2005: results June 29th Sliced view of the exosphere, down to the first part of the tail Two main features: 1. Higher intensities during the second night 2. Southern hemisphere peak June 30th July 1st
Interpretation: (Possible related solar events) Active Region AR0781 CMEs) Coronal hole on the Sun and an associated high speed stream: stream at 650-700 km/s arrived at Mercury 2-3 days before Three different CMEs from the active region AR0781 occurred during the observations: coronal hole SoHO/EIT (Fe XV 284 Å) image SOHO/LASCO CME catalog (http://cdaw.gsfc.nasa.gov/cme_list/)
CME 1: (Halo CME) 28th June halo CME speed V 0 = 1750 km/s. 16:30 UT, observed initial It was estimates that the CME decelerated from 1750 to 400km/s, in about 6h (~0.144 AU), then it reached Mercury at 0.42 AU after about 30h (hence: 30th June 2005, at about 05:00 UT). CME 2: 28th June 20:06 UT, PA = 97, AW = 68, V(?) 600 km/s Estimated arrival time @0.42 AU: 30-June, 03:00 UT (assuming the speed of 600 km/s) 30-June, 15:00 UT (assuming the speed of 400 km/s) CME 3: 29th June 07:31 UT, PA = 83, AW = 49,V(?) 350 km/s Estimated arrival time @0.42 AU: 01-July, 17:00 UT
Time sequence of the events: CME#1 CME#3 29-Jun (180) 30-Jun (181) 01-Jul (182) time 20:00 UT 20:00 UT 20:00 UT Fast Stream (176) CME#2
IMF Bx component: time 188 184 180 176 172 IMF B? x (GSE) - Mercury - + (-) IMF < 0 IMF Bx (GSE) > 0 (+) IMF > 0 IMF Bx (GSE) < 0
Tail Analysis: Potter et al., 2002: June 5th 2000 TAA= 114º May 26th 2001 TAA= 125º Our data: June 29th 2005 July 1st 2005 TAA= 124-130º
All dates display similar shape similartaas Dependance more on TAA values than on ejecting phenomena (SW)
THEMIS: observations on July 13th 2008 (08:19 20:22 local time) D2 at 5890 Å Na emission line High Resolution: Spectral range of ~4 Å Mercury s radius = 3.05 Mercury s true anomaly angle = 308.8-311.5 Heliocentric distance = 0.33 AU Heliocentric radial velocity = -7.6 km/s (towards the Sun) Phase angle 66 dusk side of Mercury Illuminated disk = 70% Slit: size 0.25 69.6 oriented along Mercury s North/South axis automatically moved between each position in a direction perpendicular to the slit.
D2 Na Emission brightness 7:30 UT 8:45 UT 10:00 UT 11:30 UT 12:45 UT 14:15 UT
D2 Na Doppler Speed 7:30 UT 8:45 UT 10:00 UT 11:30 UT Negative value: away from surface, towards the Earth 12:45 UT 14:15 UT
D2 Na spectral Doppler Width 7:30 UT 8:45 UT 10:00 UT 11:30 UT 2.8 km/s ~ 1000 K >> 600 K of surface 12:45 UT 14:15 UT
2007: May, 4 days, 14 scans October, 3 days, 18 scans 2008: April, 8 days, 44 scans July, 8 days, 52 scans September, 4 days, 7 scans November, 3 days, 5 scans 2009: April, 8 days, 73 scans June, 7 days, 33 scans July, 1 day, 3 scans August, 6 days, 32 scans October, 9 days, 43 scans THEMIS Mercury Database: 2010: May, 7 days July, 7 days June, 5 days September, 6 days
IMW (International Mercury Watch): Italy C. Barbieri U. of Padova G. Cremonese INAF, Padova C. Grava U. of Padova V. Mangano IFSI, Roma P. Borin INAF, Padova Japan S. Okano Tohoku U. M. Kagitani Tohoku U. S. Kameda PERC/Chitech France A. Doressoundiram Paris Observatory Francois Leblanc CNRS, Service d Aeronomie E. Chassefiere CNRS, Service d Aeronomie J-L. Maria CNRS, Service d Aeronomie M. Wedlund CNRS, Service d Aeronomie United States M. Mendillo Boston U., CSP J. Baumgardner Boston U., CSP J. Wilson Boston U., CSP C. Schmidt Boston U., CSP A. Sprague U. of Arizona J. Wroten Boston U., CSP
Four different telescopes: TNG (Italy) at Canary Islands: Alt-azimuth mounting Primary mirror 3.58 m HR echelle spectrograph Resolution: 115000 Na filter (60 Ǻ) CCD size: 2K x 4K pixels CFHT (France) at Hawaii: Alt-azimuth mounting Primary mirror 3.6 m HR echelle spectrograph Resolution: 80000 Spectral range: 370-1050 nm One fiber hole 1.6 arcsec Haleakala Obs.(.(Japan) at Hawaii: 40 cm telescope Fabry-Perot Interferometer Scan range 588.84-589.03 nm Plate scale 0.23 arcsec/px CCD size: 1K x 1 K pixels AEOS (USA) at Hawaii: AEOS (USA) at Hawaii: Primary mirror 3.67 m Adaptive optics Image slicer spectrograph Plate scale 0.5 arcsec/fiber Array of 20x20 optical fibers
IMW Campaign 2006 June 2006 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 CFHT (Hawaii) X TNG (Canaries) G G B G AEOS (Maui) Tohoku U. (Maui) X X X B X X X X G M B M B X X BU @ TU (Maui) X X X
Coordinated campaign in 2009-2010: April 2009 McDonald Obs. THEMIS TNG April 19th to May 1st April 17th to 24th April 20th to 24th that is 5 days of simultaneous observations June 2010 THEMIS Haleakala Obs. THEMIS Haleakala Obs. July 2010 May 31th to June 7th June 1st and 3rd July 19th to 24th July22nd and 24th that is 4 days more of simultaneous observations
IMW 2009:
What s next Usa Canaries Japan Hawaii Chile Plan to have solar telescopes comtemporary observations in 3-5 different locations in the world (almost equally separated in longitude). This would allow a full 24 hours/day coverage of the Mercury sodium exosphere observations! /tail /relaxation time.