Observation of the Airglow from the ISS by the IMAP Mission *Y

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2013/3/13(ANGWIN workshop, T a chikawa)

Observation of the airglow from the ISS by the IMAP mission

*Y. Akiya [1], A. Saito [1], T. Sakanoi [2],
Y. Hozumi [1], A. Yamazaki [3], Y. Otsuka [4]

[1] Graduation School of Science, Kyoto University , [2] PPARC, Tohoku University,
[3] ISAS/JAXA, [4] STE Laboratory, Nagoya University

----- Outline -----
Introduction of the IMAP mission Visible and near-infrared spectrographic imager Samples of airglow observation by VISI Summary

“ISS-IMAP” mission

Ionosphere, Mesosphere, Upper

Imagers of the

atmosphere and Plasmasphere mapping mission from the International Space Station (ISS)

ISS-IMAP mission

Observational imagers were installed on the Exposure Facility of Japanese Experimental Module: August 9th, 2012.

Initial checkout: August and September, 2012

Nominal observations: October, 2012 -

[Pictures: Courtesy of JAXA/NASA]

“ISS-IMAP” mission

Two imagers are set in MCE and observe from the Exposure

EUVI

Facility of Japanese Experiment Module on the ISS.

VISI (Visible and near-infrared spectrographic imager) observes airglow emission with line

VISI

scanning in the nadir direction. EUVI (Extreme ultraviolet imager) observes resonance scattering light from plasma in the upper atmosphere in the limb direction.

[Sakanoi et al., 2011]

[http://eol.jsc.nasa.gov]

Aurora
Airglow

EUVI-FOV

VISI-FOV

Extreme Ultraviolet Imager (EUVI)

Resonant scattering: 83.4 nm (O+), 30.4 nm (He+) Observation in the day side and the night side Limb observation in backward FOV 15 deg. Weight: 19.3 kg, Size: 170 mm X 370 mm X 480 mm

Initial test of
EUVI: Lid close on August 11, 2012

EUVI He+
(September 26, 2012 07:26UT)

Visible and near-infrared spectrographic imager (VISI)

Airglow: O (630 nm), OH (8-3 band around 730 nm), O2 (762 nm) Observation in the night side Nadir direction observation with FOVs pointing 45 degrees forward and 45 degrees backward

Weight: 14.5 kg, Size: 170 mm X 370 mm X 480 mm Several observational mode

ISS moving direction

Forward FOV
Backward FOV

Observational mode of VISI

Calibration mode

Calibration mode

Images are read out without binning. Full frame data are recorded.

Exposure time: 2 - 4 seconds

Spectral mode

Data at three ROIs (ROI = Region of interest) determined in the forward FOV and three ROIs in the backward FOV are recorded.

Exposure time: 1 - 6 seconds Binning: 8, 16, 32 pixels in spatial direction

Peak mode

The peak and background on each spectrum in the ROIs are determined and recorded.

Left: Spectral mode

Right: Peak mode

Exposure time and binning are same as spectral mode.

Averaged intensity of calibration data spectrum

Averaged for 56

400

calibration mode data

[6]

Forward FOV

Backward FOV

taken from August to December, 2012.

300 200

[1] 557.7nm(O) [2] 589.6nm(Na)

[3] 630.0nm(O)

[4] 636.4nm(O) [5] 732.0nm(O+)

[6] 761.9nm(O2)

[7] 777.4nm(O) [8] 844.6nm(O) [9] 864.5nm (O2)

[9]
[1]
[2]

  • [3]
  • [5]

[7]
[8]

100
0

[4]

  • 500
  • 700 800 900

600

Wavelength [nm]

Averaged intensity of OH band emissions

Average of 56 calibration mode data taken from August to December, 2012.

70 60

50 40 30 20

Forward FOV

Backward FOV

[6]
[5]
[2][3]

[1]
[4]

[1] 7-1 (560-570nm) [2] 8-2 (590-600nm)

[7]
[8]

[3] 5-0, 9-3 (620-640nm)

[4] 6-1 (650-670nm) [5] 7-2 (690-705nm)

10
0

[6] 8-3, 4-0, 9-4, 5-1 (720-810 nm)

  • 500
  • 700 800 900

600

Wavelength [nm]

[7] 6-2 (840-860nm) [8] 7-3 (880-900nm)

762-nm Peak mode observation

Observation around 2012/9/25 02:15 UT

762-nm (95 km altitude)
Background

630-nm Peak mode observation

Observation around 2012/9/25 02:15 UT

630-nm (250 km altitude)
Background

Calibration and flattening of observational data

White pixels are already subtracted from the observational data.

1000

Two strong lines are seen in the

800

762-nm forward FOV peak image. These are also seen in background images.

600

The strength of this effect is not uniform in the same observation. Strength is

affected by the intensity of the light passed the optical system.

Coordinate [pixel]
400

0 10 20 30 40 50 60

Summary

ISS-IMAP mission started the observation of the upper atmosphere in August. Nominal observations by VISI and EUVI has been carried out.

VISI observes the airglow in the nadir direction with two field of views. Target is the airglow originated from the atomic oxygen (630-nm wavelength), OH molecules (0-0 band) and oxygen molecules (762- nm wavelength). It is able to observe 557.7-nm emission from the atomic oxygen, Na emission and other OH band emissions in calibration mode observation.

It is needed to subtract noise caused by electric interference and nonuniformity of optical slit. Noise caused from electrical part has same phase and appearance. On the other hand, noise caused from optical part is different in every observation. Calibration of observational data is needed.

Sensitivity between two field-of-views of VISI are slightly different. This is also thought to be caused from the non-uniformity of the slit width.

Ground-based airglow observations

ALOHA-93 campaign FRONT campaign OMTI: Optical Mesosphere Thermosphere Imagers

Another ground-based airglow imager will be put at Hawaii as a part of

Observations of OH airglow by OMTI [Shiokawa et al., 1999]

ISS-IMAP project.

Airglow observation from space shuttle

Observed by GLO-1 during the STS 53 shuttle mission [Broadfoot et al., 1999]

Many observations of the airglow are made by the ground-based imager, rockets and satellites.

Airglow is observed with spectrographic image in the

nadir direction in the ISS-IMAP mission.

Airglow observations by rockets and satellites

Example of rocket observations (Photometer of TOMEX project) are shown in the right figures

TIMED satellite WINDII, HRDI on UARS satellite

ISUAL/FORMOSAT-2 Multi-spectral auroral camera on INDEX (Reimei) satellite

[Hecht et al., 2004]

Airglow observation from space shuttle

Observed by GLO-1 during the STS 53 shuttle mission [Broadfoot et al., 1999]

View of ISS-IMAP instruments in “MCE”

MCE = Multi-mission consolidated equipment

1.8 m x 1.0 m x 0.8 m, 450 kg weight

EUVI(IMAP)

SIMPLE

Five missions (IMAP, GLIMS, SIMPLE, REXJ and HDTV) uses a single port this time.

REXJ
GLIMS

VISI(IMAP)

HDTV

Specification of VISI

Size 450 mm x 240 mm x 210 mm

  • Weight
  • 14.5 kg

e2V 47-20 back-illuminated AIMO, 1024 x 1024 pixels
1 pixel size = 13.3μm x 13.3μm
CCD sensor

Rectangular shaped
(90 x 0.09 deg)
FOVs pointing 45 degrees forward and 45 degrees backward
Field-ofview
(FOV)

Objective lens
F/0.96, f = 5.5 mm

ISS moving direction

Forward FOV

Spectrosc Wavelength coverage: 600 - opic 800 nm in the both FOVs properties Resolutions ~ 1.0nm / pixel

Backward FOV

Specification data:[Sakanoi et al., 2011]

Observational target of VISI

Atomic oxygen (O) airglow
630-nm wavelength ~ 250 km altitude (F2 layer), ~ 100 kR
OH molecule airglow observes in 730-nm wavelength ~ 87 km altitude, ~ 1kR
Oxygen molecule (O2) airglow
762-nm wavelength ~ 100 km altitude

630-nm emission from atomic oxygen

O(1D) → O(3P2) + hν(630.0nm) O(1D) → O(3P1) + hν(636.4nm) O(1D) → O(3P0) + hν(639.2nm) Intensity of 630.0-nm wavelength emission at night is ~100 kR

The lifetime of the excited state (1D) of the atomic oxygen is ~134 seconds. These atoms radiates at the altitude of ~250 km (~F2 layer).

762-nm emission from oxygen molecule

The emission from oxygen molecule O2(b1Σ+ )

g

→ O2(X3Σ-g) has two intense bands:
761.9-nm, (0-0) band 864.5-nm, (0-1) band
Radiative lifetime of metastable molecules is ~12 seconds. These molecules emit at the altitude in 90 - 100 km. These emissions are usually absorbed by the Earth atmosphere and difficult to observe from the ground.

Hydroxyl emissions

Hydroxyl emission arises in the upper atmosphere at ~87 km altitude. Average intensity of this emission is ~ 1 kR.

(8-3) band is around 730-nm wavelength OH molecules are thought to be produced by the reactions in below. (M = O2 or N2)

The ozone-hydrogen reaction: O + O2 + M → O3 + M H + O3 → OH + O2

The reaction of perhydroxyl with atomic oxygen: H + O2 + M → HO2 + M O + HO2 → OH + O2

Data processing

Camera format data

VISI raw data

Take out observational data

tfb data One file for one raw data file

Separate data into groups for each observations

decoded data One file for one snap shot

Refer the ROM table (Observational mode, Exposure time), sensitivity
Make continuous data file for one observation

Level-1 data

One file for one observation (one mode)

IDL routines q - parameters, transfer to absolute

intensity, FOV angle

plotted data

altitude, attitude

JPEG, FITS, IDL save

Level-2 data “Science” data

Example data of Calibration mode

# Version: 1.0 # Program: visi_level1_make.pro (Ver. 1.0) # Creator: T. Sakanoi

←Version of data ←IDL procedure used ←Data creator

# Create Date: Mon Oct 1 14:43:55 2012

←Created date

# Data File Start: IMP_EXP_2012-09-05.log_tfb_VISI3706_12090509452305_TBL14_0543207_decode.dat # Data File End :

←First decoded data

IMP_EXP_2012-09-05.log_tfb_VISI3706_12090509452305_TBL14_0543207_decode.dat

←Last decoded data

  • # Data File Number:
  • 1

←Number of shots in the observation

# VISI Table Version: 2012-02-21 # Mode:

←Date of ROM table updated ←Observational mode (No description for CAL mode) ←Binning ←Exposure time ←Exposure time + read out

# Binning Number (a) (pix): # Exposure Time (b) (sec)= # Exposure Cycle (sec)=
32
6.00000
6.58800
# X-pix, Y-Pix, ROI number= 1028 1072 # Unit: Counts in a exposure time
1

←Number of pixels in Spatial, Wavelength and number of ROI ←Physical unit of the data in below
←Sensitivity

←Mode of gain

# Sensitivity at 630,730,762nm (c) (el/R/pix/sec): 0.0320000 0.0320000 0.0300000 # Gain : # Conversion Factor from Count to Electron (e) :
0

←Relation between counts and electrons

1.24000
# NOTICE: You get intensity in Rayleigh by Count*(e)/(a)/(b)/(c) # END OF HEADER

←Number of file is 1 if 0/0 ←Time of observational shot (←This description can be ignored in CAL mode)

File number= Date, UT(hhmmss)= 20120905 094523 O 630nm, Backward,ROI= 5/

  • 0/
  • 0

6
691 691 690 689 692 689 688 688 688 686 688 691 689 691 684 686 688 686 690 693

←Data are written in below

Example data of Spectral mode

# Version: 1.0 # Program: visi_level1_make.pro (Ver. 1.0) # Creator: T. Sakanoi # Create Date: Mon Oct 1 14:43:44 2012 # Data File Start: IMP_EXP_2012-09-05.log_tfb_VISI0001_12090500212205_TBL01_0003986_decode.dat # Data File End : IMP_EXP_2012-09-05.log_tfb_VISI0001_12090500212205_TBL01_0003986_decode.dat

  • # Data File Number:
  • 1

# VISI Table Version: 2012-02-21 # Mode: Spectral mode # Binning Number (a) (pix): # Exposure Time (b) (sec)= # Exposure Cycle (sec)= # X-pix, Y-Pix, ROI number=
16
1.00000
1.86200

  • 64
  • 12
  • 6

# Unit: Counts in a exposure time # Sensitivity at 630,730,762nm (c) (el/R/pix/sec): 0.0320000 0.0320000 0.0300000 # Gain : # Conversion Factor from Count to Electron (e) :
0
1.24000
# NOTICE: You get intensity in Rayleigh by Count*(e)/(a)/(b)/(c) # END OF HEADER

←Number of file is 1 if 0/0 ←Time of observational shot ←Source of emission, wavelength, observed FOV, ROI number

File number= Date, UT(hhmmss)= 20120905 002122 O2 762nm, Forward, ROI= 0/

  • 0/
  • 0

6
521 521 522 530 585 536 3488 556 551 543 539 564 613 532 539 535 544 531 533 535 536 538 699 548 542 550 557 567 567 571 561 561 551 561 561 551 558 558 575 579 583 575 564 558 544 554 539 583 542 540 535 533 535 527 525 533 531 528 525 519 517 521 519 491

←Data are written in below

Example data of Peak mode

# Version: 1.0 # Program: visi_level1_make.pro (Ver. 1.0) # Creator: T. Sakanoi # Create Date: Mon Oct 1 14:43:45 2012 # Data File Start: IMP_EXP_2012-09-05.log_tfb_VISI0002_12090500212505_TBL07_0000981_decode.dat # Data File End : IMP_EXP_2012-09-05.log_tfb_VISI0662_12090500422405_TBL07_0000912_decode.dat

  • # Data File Number:
  • 661

# VISI Table Version: 2012-02-21 # Mode: Peak mode # Binning Number (a) (pix): # Exposure Time (b) (sec)= # Exposure Cycle (sec)= # X-pix, Y-Pix, ROI number=
16
1.00000
1.86200

  • 64
  • 2
  • 6

# Unit: Counts in a exposure time # Sensitivity at 630,730,762nm (c) (el/R/pix/sec): 0.0320000 0.0320000 0.0300000 # Gain : # Conversion Factor from Count to Electron (e) :
0
1.24000
# NOTICE: You get intensity in Rayleigh by Count*(e)/(a)/(b)/(c) # END OF HEADER

←1st data of 660 data in this observation ←Time of observational shot ←Source of emission, wavelength, observed FOV, ROI number

File number= Date, UT(hhmmss)= 20120905 002125 O2 762nm, Forward, ROI= 0/

  • 0/
  • 660

6
548 870 861 848 902 959 546 519 537 537 531 532 533 523
551 924 875 872 907 976 548 524 539 540 527 536 539 520
550 910 843 876 935 953 540 523 538 540 533 537 528 515
557 922 843 893 964 928 2489 532 520 535 530 531 539 533 499
628 919 844 891 980
613 871 866 1191 850 979
890
858 861
840 850
860
871 925
791
820 881
850
926 908
554
826 881
846
936 935
548
841 955
892

←Peak data

565 528 527 535 534 528
545 534 535 529 537 526
666 531 529 530 538 537
578 530 537 531 534 528
549 535 531 537 543 520
545 532 534 532 542 520

←Background data

Calibration mode image

2012/8/13 03:25:08 UT Exposure time: 6 seconds Line dispersion: 0.90 nm/pixel in forward FOV, 1.02 nm/pixel in backward FOV

Region for ~600 km is taken in spatial direction

Forward FOV

Wavelength

Backward FOV

Wavelength

Count values on CCD

570 560 550 540

Backward
FOV

Counts shown in the right figure are averaged for 60 pixels in each regions.

Forward
FOV

530

650 850
750

550 650 750

Wavelength [nm]

Wavy structure caused from mechanical part of imager is seen in the backward FOV.

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    Modern Astronomical Optics 1. Fundamental of Astronomical Imaging Systems OUTLINE: A few key fundamental concepts used in this course: Light detection: Photon noise Diffraction: Diffraction by an aperture, diffraction limit Spatial sampling Earth's atmosphere: every ground-based telescope's first optical element Effects for imaging (transmission, emission, distortion and scattering) and quick overview of impact on optical design of telescopes and instruments Geometrical optics: Pupil and focal plane, Lagrange invariant Astronomical measurements & important characteristics of astronomical imaging systems: Collecting area and throughput (sensitivity) flux units in astronomy Angular resolution Field of View (FOV) Time domain astronomy Spectral resolution Polarimetric measurement Astrometry Light detection: Photon noise Poisson noise Photon detection of a source of constant flux F. Mean # of photon in a unit dt = F dt. Probability to detect a photon in a unit of time is independent of when last photon was detected→ photon arrival times follows Poisson distribution Probability of detecting n photon given expected number of detection x (= F dt): f(n,x) = xne-x/(n!) x = mean value of f = variance of f Signal to noise ration (SNR) and measurement uncertainties SNR is a measure of how good a detection is, and can be converted into probability of detection, degree of confidence Signal = # of photon detected Noise (std deviation) = Poisson noise + additional instrumental noises (+ noise(s) due to unknown nature of object observed) Simplest case (often
  • Introducing the Bortle Dark-Sky Scale

    Introducing the Bortle Dark-Sky Scale

    observer’s log Introducing the Bortle Dark-Sky Scale Excellent? Typical? Urban? Use this nine-step scale to rate the sky conditions at any observing site. By John E. Bortle ow dark is your sky? A Limiting Magnitude Isn’t Enough precise answer to this ques- Amateur astronomers usually judge their tion is useful for comparing skies by noting the magnitude of the observing sites and, more im- faintest star visible to the naked eye. Hportant, for determining whether a site is However, naked-eye limiting magnitude dark enough to let you push your eyes, is a poor criterion. It depends too much telescope, or camera to their theoretical on a person’s visual acuity (sharpness of limits. Likewise, you need accurate crite- eyesight), as well as on the time and ef- ria for judging sky conditions when doc- fort expended to see the faintest possible umenting unusual or borderline obser- stars. One person’s “5.5-magnitude sky” vations, such as an extremely long comet is another’s “6.3-magnitude sky.” More- tail, a faint aurora, or subtle features in over, deep-sky observers need to assess the galaxies. visibility of both stellar and nonstellar ob- On Internet bulletin boards and news- jects. A modest amount of light pollution groups I see many postings from begin- degrades diffuse objects such as comets, ners (and sometimes more experienced nebulae, and galaxies far more than stars. observers) wondering how to evaluate To help observers judge the true dark- the quality of their skies. Unfortunately, ness of a site, I have created a nine-level most of today’s stargazers have never scale.
  • Special Issue Editorial: Atmospheric Airglow—Recent Advances in Observations, Experimentations, and Modeling

    Special Issue Editorial: Atmospheric Airglow—Recent Advances in Observations, Experimentations, and Modeling

    atmosphere Editorial Special Issue Editorial: Atmospheric Airglow—Recent Advances in Observations, Experimentations, and Modeling Tai-Yin Huang Department of Physics, Penn State Lehigh Valley, Center Valley, PA 18034, USA; [email protected] Airglow observations, experimentations, and theoretical studies have significantly advanced our understanding of airglow in recent decades. This Special Issue is a collec- tion of recent studies to showcase the latest results from studies in airglow observations, experimentations, and numerical modeling in the Mesosphere and Lower Thermosphere (MLT) and F regions of the terrestrial atmosphere. There are three main themes in this Special Issue. The first theme is focused on the use of satellite measurements to study the variabilities observed in the airglow emissions. The second theme is focused on ground- based observations of airglow to characterize gravity waves. The third theme is focused on airglow modeling. The recent (NASA) Global-scale Observations of the Limb and Disk (GOLD) mission provides a unique new view of the daytime thermosphere. Immel et al. [1] studied the daily variability in the UV airglow (OI and N2 in the 133–168-nm range) observed by the GOLD mission to characterize the behavior of these constituents of the thermosphere. Their results indicate that oxygen densities in the altitude range of 150–200 km vary independently from the variations in nitrogen. Yue et al. [2] performed a preliminary comparison between airglow-based Atmospheric Gravity Wave (AGW) observations from two space-borne Citation: Huang, T.-Y. Special Issue sensors, the Visible/Infrared Imaging Radiometer Suite/Day-Night Band (VIIRS/DNB) Editorial: Atmospheric Airglow— and the Ionosphere, Mesosphere, upper Atmosphere and Plasmasphere/Visible and near- Recent Advances in Observations, Infrared Spectral Imager (IMAP/VISI).
  • Three-Dimensional Tomographic Reconstruction of Mesospheric Airglow Structures Using Two-Station Ground-Based Image Measurements

    Three-Dimensional Tomographic Reconstruction of Mesospheric Airglow Structures Using Two-Station Ground-Based Image Measurements

    Three-dimensional tomographic reconstruction of mesospheric airglow structures using two-station ground-based image measurements Vern P. Hart,1,* Timothy E. Doyle,2 Michael J. Taylor,1,4 Brent L. Carruth,3 Pierre-Dominique Pautet,4 and Yucheng Zhao4 1Department of Physics, Utah State University, 4415 Old Main Hill, Logan, Utah 84322, USA 2Department of Physics, Utah Valley University, 800 West University Parkway, MS 179, Orem, Utah 84058, USA 3Department of Electrical and Computer Engineering, Utah State University, 4120 Old Main Hill, Logan, Utah 84322, USA 4Center for Atmospheric and Space Sciences, Utah State University, 4405 Old Main Hill, Logan, Utah 84322, USA *Corresponding author: [email protected] Received 15 June 2011; revised 4 November 2011; accepted 14 December 2011; posted 16 December 2011 (Doc. ID 149292); published 29 February 2012 A new methodology is presented to create two-dimensional (2D) and three-dimensional (3D) tomographic reconstructions of mesospheric airglow layer structure using two-station all-sky image measurements. A fanning technique is presented that produces a series of cross-sectional 2D reconstructions, which are combined to create a 3D mapping of the airglow volume. The imaging configuration is discussed and the inherent challenges of using limited-angle data in tomographic reconstructions have been analyzed using artificially generated imaging objects. An iterative reconstruction method, the partially constrained al- gebraic reconstruction technique (PCART), was used in conjunction with a priori information of the air- glow emission profile to constrain the height of the imaged region, thereby reducing the indeterminacy of the inverse problem. Synthetic projection data were acquired from the imaging objects and the forward problem to validate the tomographic method and to demonstrate the ability of this technique to accu- rately reconstruct information using only two ground-based sites.
  • ISS-IMAP Observation of the Airglow and the Ion Resonant Scattering in the Earth’S Upper Atmosphere

    ISS-IMAP Observation of the Airglow and the Ion Resonant Scattering in the Earth’S Upper Atmosphere

    PEM11-04 Room:A01 Time:May 24 17:10-17:25 ISS-IMAP observation of the airglow and the ion resonant scattering in the Earth’s upper atmosphere SAITO, Akinori1¤ ; SAKANOI, Takeshi2 ; YOSHIKAWA, Ichiro4 ; YAMAZAKI, Atsushi3 ; OTSUKA, Yuichi5 ; YAMAMOTO, Mamoru1 ; AKIYA, Yusuke1 ; HOZUMI, Yuta1 ; YUKINO, Hideko1 1Kyoto University, 2Tohoku Uniersity, 3University of Tokyo, 4JAXA, 5Nagoya University ISS-IMAP (Ionosphere, Mesosphere, upper Atmosphere, and Plasmasphere mapping) mission have observed the airglow and the ion resonant scattering in the Earth’s upper atmosphere since 2012. The scientific goals of ISS-IMAP are to elucidate following two processes: 1) energy transport process by the structures whose horizontal scale is 50-500km in the Earth’s upper atmosphere, 2) the effect of the structures and disturbances on the space-borne engineering system. ISS-IMAP was installed on the Exposure Facility of Japanese Experiment Module, Kibo, of the International Space Station in August 2012. It consists of two sets of imagers, VISI and EUVI. Visible-light and infrared spectrum imager (VISI) observes the Mesosphere and the Ionosphere. Extra ultraviolet imager (EUVI) observes the Ionosphere and the Plasmasphere. VISI observes the airglow in the Nadir direction. The airglow emissions were mainly observed by VISI was 730nm (OH, Alt. 85km), 762nm (O2, Alt. 95km), and 630nm (O, Alt. 250km). Additional airglows, such as Sodium, were also observed. The global distributions of the airglow structures whose scale size is 50-500km in the nightside of the Mesosphere and the Ionosphere have been obtained by the VISI observation. EUVI measures the resonant scattering of 30.4nm [He+] and 83.4nm [O+].