• 천문학회보
• /
• 제41권1호
• /
• pp.48.3-49
• /
• 2016

Current high-resolution IR spectroscopy at ground-based observatories made it possible to observe $3-{\mu}m\;CH_4$ emission lines from the atmospheres of Jupiter, Saturn, and Titan through narrow atmospheric windows avoiding the counterparts of telluric $CH_4$ absorptions if proper Doppler shifts betwen Earth and these planetary objects are provided. We are also expecting low-resolution (R~300) infrared spectra of Jupiter from the upcoming observations by JUNO's infrared $2-5{\mu}m$ spectrograph during the encounter with Jupiter approximately starting from July 4, 2016. Although the spectral resolution is not enough to resolve the $3-{\mu}m$ P, Q, R branch lines of CH4, the gross envelopes of the P, Q, R branches should yield information on rotational temperatures. The rotational temperatures are useful because theycan be regarded as local temperatures, as discussed by Kim et al. (2014). Since the $3-{\mu}m\;CH_4$ emission is mostly formed at micro-bar pressure levels, the derived rotational temperatures represent the local temperatures near the hompause of Jupiter. We discuss possible sciences from the derived homopause temperatures in the auroral and non-auroral regions of Jupiter.

• 천문학회지
• /
• 제38권4호
• /
• pp.471-478
• /
• 2005

Spectroscopic data obtained by the Infrared Interferometer Spectrometer (IRIS) aboard Voyager 1 and 2 have been re-visited. Using the spectroscopic data and footprints of the IRIS aperture on the planet, we constructed images of the stratosphere of Jupiter at the emission bands of hydrocarbons including $CH_4,\;C_2H_6,\;C_2H_2,\;C_3H_4,\;C_6H_6$, and $C_2H_4$. Thermal emission from the hydrocarbons on Jupiter originates from a broad region of the stratosphere extending from 1 to 10 millibars. We averaged the data using a bin of 20 degrees of longitude and latitudes in order to increase signal-to-noise ratios. The resultant images show interesting wave structure in Jupiter's stratosphere. Fourier transform analyses of these images yield wavenumbers 5 - 7 at mid-Northern and mid-Southern latitudes, and these results are different from those resulted from previous ground-based observations and recent Cassini CIRS, suggesting temporal variations on the stratospheric infrared pattern. The comparisons of the Voyager 1 and 2 spectra also show evidence of temporal intensity variations not only on the infrared hydrocarbon polar brightenings of hydrocarbon emissions but also on the stratospheric infrared structure in the temperate regions of Jupiter over the 4 month period between the two Voyager encounters. Short running title: Stratospheric Images of Jupiter derived from Voyager IRIS Spectra.

• 천문학회보
• /
• 제37권1호
• /
• pp.100.2-100.2
• /
• 2012

We have investigated excitation processes of the 3-micron bands of $CH_4$, $C_2H_2$, and $C_2H_6$ over the auroral regions of Jupiter including particle bombardments, Joule heating, scattering of solar radiation, and possible chemiluminescence. We also considered possible LTE or Non-LTE conditions of these processes. We constructed particle precipitation models including $H_2$, He, H, and the hydrocarbon molecules for the atmosphere of the auroral regions. We present preliminary results from these models, and comparisons of the model results with spectroscopic observations in the 3 micron wavelength range of Jupiter.

• 천문학회보
• /
• 제40권1호
• /
• pp.90.1-90.1
• /
• 2015

Almost hot-Super Earths ($R_p$~1 to $4R_{earth}$ orbital period < 100 days) are around Sun-like stars. But our solar system does not have hot-Super Earth. Andre et al. 2015 has explained this phenomenon by that Jupiter blocks migration of super earth. We have found a multi-planetary system KOI-94 with exo-Jupiter and hot-Super Earth from NASA exoplanet archive data (http://exoplanetarchive.ipac.caltech.edu). In this study, within multi-planetary systems including hot-Super Earth, we compared those with and without exo-Jupiter using their host star and exoplanet parameters, such as metallicity [Fe/H], $T_{eff}$ and $R_*/R_p$.

• 천문학회지
• /
• 제28권1호
• /
• pp.89-95
• /
• 1995

We examined a total of 166 images of $3.5{\mu}m\;H_3^+$ emission in the auroral regions of Jupiter observed with the Protocam on IRTF in 1991 and 1992, and found that 30 images contain a clearly isolated small emission patch in the vicinity of the northern auroral regions. Two different time sequences of the images show the small patches at the dusk limb in the range of System III longitudes from $270^{\circ}\;through\;0^{\circ}\;to\;90^{circ}$. The small patches in one sequence of the images, which were taken at 10 phase between $240^{\circ}\;and\;260^{\circ}$, may be related to the 10 flux tube, similarly suggested by Connerney et al. (1993). However, the small patches in the other sequence are separated from Io as much as $80^{\circ}$ in longitude. The positions of the small patches in both sequences are deviated equatorward from the 10 footprint oval by $5^{\circ}-8^{\circ}$ latitude in the longitudinal range of $270^{\circ}-360^{\circ}$. A significant modification is required in current Jovian magnetic field models near the Jupiter's surface if the small patches are produced at the foot of the 10 flux tube.

• 한국콘텐츠학회논문지
• /
• 제18권9호
• /
• pp.498-509
• /
• 2018

<쥬피터 어센딩>은 앞선 SF영화와는 사뭇 다른 철학적인 사상이 내포되어 있다. 그 사상은 제카리아 시친의 사상을 차용한 것이다. 시친은 아주 독특한 관점에서 지구 및 인류의 역사를 이야기 하고 있다. 우리 인류는 이 행성의 지적생명체(인간은 그들을'신'이라 불렀다고 한다)가 인류를 창조하고 고대의 문명도 그들이 가져다주었다는 것이다. 본 연구에서는 제카리아 시친의 사상이 학계와 종교계에 비상한 관심 속에 있고 그의 사상들이 현재 발굴되어지고 있는 고고학적 증거들에 의해서 많은 부분들이 지구상의 미스터리들을 해결하는 쾌거를 보여주고 있는 시점에서 SF영화라는 예술장르와의 비교분석이 가능하다는 판단아래 <쥬피터 어센딩>의 분석을 진행 하여 시친이 전하고자 하는 메시지와 SF영화의 두 요소사이의 공감대를 형성할 수 있었던 요인을 찾고 시친과 SF영화<쥬피터 어센딩>의 내러티브에 등장하는 교차영역을 중심으로 시친의 사상을 찾아 분석 한다.

• Journal of Astronomy and Space Sciences
• /
• 제5권2호
• /
• pp.129-141
• /
• 1988

제한 3체 문제의 수치해를 이용하여 태양-목성계와 지구-달계의 $L_5$점 근처에서 각각 490여개, 1,600여개의 주기 궤도를 구하였다. 태양-목성계의 경우에서는 주기의 증가에 따라 에너지와 주기 궤도 크기가 단조롭게 커졌다. 그러나 지구-달계에서의 주기 궤도 모양은 복잡하고 변곡점이 나타나며 서로 겹치는 경우도 있다. 또한, 지구-달계에서 단일주기에 3개의 에너지가 동시 대응하는 영역이 존재하며 이 영역에소는 주기와 에너지가 반비례하는 구역이 있다. 태양-목성계의 $L_5$ 점 근처에서 목성의 중력 섭동 외의 기타의 작은 섭동에 의해 불안정한 주기 궤도가 될 수 있는 영역이 존재 가능하다. 이 영역 중 $L_5$점(5.2AU)에 가장 가까운 지역들이 a~5.12AU와 a~5.29AU 근처인데, 이 곳에는 이심률과 궤도 경사각이 작은 Trojan 소행성들이 존재하기 어렵다고 할 수 있다.

• 천문학논총
• /
• 제10권1호
• /
• pp.1-14
• /
• 1995

We observed impact spots on Jupiter which were formed by the collision with fragments of Shoemaker-Levy 9 comet during the period from 17 July to 13 August, by using the SNU 61cm reflector combined with CCD camera and DBVRI filters. In order to get more clear image of impact spots, the observed data were processed by the unsharp masking method, high-pass filtering method and Richardson-Lucy algorithm after the basic processing through IRAF package. The sizes of impact spots range from 2000km to 1000km, and from this size, the original size of comet fragments before collision with Jupiter is estimated to be less than ${\sim}3km$. From the observed rotating rate of impact spots, the rotational period of Jupiter is determined as $9^h$ $56^m$ $32^s$ at the southern latitude of $47^{\circ}{\sim}49^{\circ}$.

• 천문학회보
• /
• 제41권2호
• /
• pp.50.1-50.1
• /
• 2016

We have found cool homopause temperatures (Kim et al. 2016) of 180 - 250 K for the 8-micron North Polar Hot Spot (8NPHS) of Jupiter, which has been observed to be stationary at 180 deg (SysIII) longitude since the early 1980s. The 3-micron spectro-images of Jupiter that we analyzed were obtained with GNIRS, Gemini Near-Infrared Spectrograph at Gemini North on January 13, 2013(UT), and at $8{\mu}m$ on Feburary 6, 2013(UT) with TEXES, the Texas Echelon Cross Echelle Spectrograph at the NASA IRTF. The cool homopause was unexpected, and a possible implication of the relatively cool 8NPHS homopause compared with those of other auroral regions will be presented.

• 천문학회보
• /
• 제43권1호
• /
• pp.72.1-72.1
• /
• 2018

Recently, an analysis of 3-micron spectra of CH4 line emission from our Gemini/GNIRS observations of Jupiter's polar regions yielded an unexpected result: The homopause (~1 microbar pressure level) located directly above the long-lasting 8-micron CH4 north-polar hot spot (Great 8-micron Hot Spot: GHS) is cool compared with the temperatures of nearby auroral regions (Kim et al. 2017). Most of the 8-micron emission of the GHS originates from CH4 at the ~1 mbar level (i.e., deeper in the stratosphere, where cooling time is several years), much longer than at the altitude of the homopause. We propose a mechanism to explain the temperature difference: locally-fixed and transient, but energetic auroral particles, which can penetrate to the 1 mbar level and deposit energy there creating and maintaining the GHS. For Saturn, thus far we have not detected distinctive 8-micron nor 3-micron CH4 hot spots in the polar regions. We will present a possible implication for this difference between Jupiter and Saturn.