scholarly journals Fitting Zodiacal Models

2001 ◽  
Vol 204 ◽  
pp. 157-160 ◽  
Author(s):  
Edward L. Wright
Keyword(s):  
Solar System ◽  
Radiation Field ◽  
Measured Data ◽  
Low Earth Orbit ◽  
Earth Orbit ◽  
Zodiacal Light ◽  
Extragalactic Background Light ◽  
Background Light

Models of the zodiacal light are necessary to convert measured data taken from low Earth orbit into the radiation field outside the Solar System. The uncertainty in these models dominates the overall uncertainty in determining the extragalactic background light for wavelengths λ < 100 μm.

scholarly journals Extragalactic background light measurements and applications

2016 ◽  
Vol 3 (3) ◽  
pp. 150555 ◽  
Author(s):  
Asantha Cooray
Keyword(s):  
Solar System ◽  
Galaxy Formation ◽  
Interplanetary Dust ◽  
Absorption Feature ◽  
Electromagnetic Spectrum ◽  
Zodiacal Light ◽  
Small Aperture ◽  
Extragalactic Background Light ◽  
Background Light ◽  
Optical Background

This review covers the measurements related to the extragalactic background light intensity from γ-rays to radio in the electromagnetic spectrum over 20 decades in wavelength. The cosmic microwave background (CMB) remains the best measured spectrum with an accuracy better than 1%. The measurements related to the cosmic optical background (COB), centred at 1 μm, are impacted by the large zodiacal light associated with interplanetary dust in the inner Solar System. The best measurements of COB come from an indirect technique involving γ-ray spectra of bright blazars with an absorption feature resulting from pair-production off of COB photons. The cosmic infrared background (CIB) peaking at around 100 μm established an energetically important background with an intensity comparable to the optical background. This discovery paved the way for large aperture far-infrared and sub-millimetre observations resulting in the discovery of dusty, starbursting galaxies. Their role in galaxy formation and evolution remains an active area of research in modern-day astrophysics. The extreme UV (EUV) background remains mostly unexplored and will be a challenge to measure due to the high Galactic background and absorption of extragalactic photons by the intergalactic medium at these EUV/soft X-ray energies. We also summarize our understanding of the spatial anisotropies and angular power spectra of intensity fluctuations. We motivate a precise direct measurement of the COB between 0.1 and 5 μm using a small aperture telescope observing either from the outer Solar System, at distances of 5 AU or more, or out of the ecliptic plane. Other future applications include improving our understanding of the background at TeV energies and spectral distortions of CMB and CIB.

In-Situ Resource Utilization

2019 ◽  
pp. 193-210
Author(s):  
Claas Tido Olthoff ◽  
Philipp Reiss
Keyword(s):  
Solar System ◽  
Resource Utilization ◽  
Local Environment ◽  
Low Earth Orbit ◽  
Background Information ◽  
Earth Orbit ◽  
Use Of Resources ◽  
Exploration Mission ◽  
The Cost

Human spaceflight is an expensive endeavor. Every kilogram that needs to be transported to low Earth orbit or beyond costs tens of thousands of dollars, with the cost increasing exponentially the farther humanity extends its reach into the solar system and beyond. It is therefore prudent, if not necessary, to consider the use of resources that are available at the destination of a given exploration mission. This concept is called in-situ resource utilization (ISRU). The processes that are required to extract useful materials from the local environment can not only be used to support a human crew, but also to obtain resources that are of value on Earth and can thus be returned there for commercial gain. This chapter provides background information on ISRU in general and discusses the most important technologies and processes that are currently employed or under development.

Geomagnetic field mapping

2020 ◽  
Vol 1 (1) ◽  
pp. 22-29
Author(s):  
Jan Jurica
Keyword(s):  
Solar Flares ◽  
Geomagnetic Field ◽  
Cosmic Radiation ◽  
Measured Data ◽  
Low Earth Orbit ◽  
Earth Orbit ◽  
Magnetic Pole ◽  
The Earth ◽  
North Magnetic Pole ◽  
Time Periods

This work focuses on creating maps of the geomagnetic field and areas of increased cosmic radiation surrounding the Earth. Data were measured by Proba-V satellite at Low-Earth orbit 820 kilometres above the Earth during 2015. The actual measured data were compared with the calculated magnetic values. The created maps serve to a better understanding of the shape of the geomagnetic field and show magnetic equator, north magnetic pole and more. The map confirms that the area of the South Atlantic Anomaly corresponds with the weakest area of the geomagnetic field. Maps of different time periods of 2015 show small changes in the shape of the geomagnetic field during a year. Increased attention was paid to June 2015, when solar flares were passing near the Earth. The observation confirms that solar flares have a significant effect on the shape of the geomagnetic field.

scholarly journals Spectrophotometric measurement of the Extragalacic Background Light

2011 ◽  
Vol 7 (S284) ◽  
pp. 429-436 ◽  
Author(s):  
Kalevi Mattila ◽  
Kimmo Lehtinen ◽  
Petri Väisänen ◽  
Gerhard von Appen-Schnur ◽  
Christoph Leinert
Keyword(s):  
Scattered Light ◽  
Spectral Lines ◽  
Spectral Signature ◽  
Zodiacal Light ◽  
Differential Measurement ◽  
Extragalactic Background Light ◽  
Background Light ◽  
The Difference ◽  
Lower Limits ◽  
Night Sky Brightness

AbstractThe Extragalactic Background Light (EBL) at UV, optical and NIR wavelengths consists of the integrated light of all unresolved galaxies along the line of sight plus any contributions by intergalactic matter including hypothetical decaying relic particles. The measurement of the EBL has turned out to be a tedious problem. This is because of the foreground components of the night sky brightness, much larger than the EBL itself: the Zodiacal Light (ZL), Integrated Starlight (ISL), Diffuse Galactic Light (DGL) and, for ground-based observations, the Airglow (AGL) and the tropospheric scattered light. We have been developing a method for the EBL measurement which utilises the screening effect of a dark nebula on the EBL. A differential measurement in the direction of a high-latitude dark nebula and its surrounding area provides a signal that is due to two components only, i.e. the EBL and the diffusely scattered ISL from the cloud. We present a progress report of this method where we are now utilising intermediate resolution spectroscopy with ESO's VLT telescope. We detect and remove the scattered ISL component by using its characteristic Fraunhofer line spectral signature. In contrast to the ISL, in the EBL spectrum all spectral lines are washed out. We present a high quality spectrum representing the difference between an opaque position within our target cloud and several clear OFF positions around the cloud. We derive a preliminary EBL value at 400 nm and an upper limit to the EBL at 520 nm. These values are in the same range as the EBL lower limits derived from galaxy counts.Unit: We will use in this paper the abbreviation 1 cgs = 10−9erg s−1cm−2sr−1Å−1

Twinkle: a low-Earth orbit, visible and infrared observatory for exoplanet and solar system spectroscopy

2021 ◽  
Author(s):  
Billy Edwards ◽  
Marcell Tessenyi ◽  
Ian Stotesbury ◽  
Richard Archer ◽  
Ben Wilcock ◽  
...  
Keyword(s):  
Solar System ◽  
Near Infrared ◽  
Surface Composition ◽  
Space Mission ◽  
Low Earth Orbit ◽  
Earth Orbit ◽  
Spectral Signatures ◽  
Solar System Objects ◽  
Scientific Potential ◽  
Asteroids And Comets

&lt;div&gt;The Twinkle Space Mission is a space-based observatory that has been conceived to measure the atmospheric&amp;#160;composition of exoplanets, stars and solar system objects. Twinkle&amp;#8217;s collaborative multi-year global survey programmes&amp;#160;will deliver visible and infrared spectroscopy of thousands of objects within and beyond our solar system, enabling&amp;#160;participating scientists to produce world-leading research in planetary and exoplanetary science.&lt;/div&gt; &lt;div&gt;&amp;#160;&lt;/div&gt; &lt;p&gt;Twinkle&amp;#8217;s rapid pointing and non-sidereal tracking capabilities will enable the observation of a diverse array of Solar System objects, including asteroids and comets. Twinkle aims to provide a visible and near-infrared (0.5-4.5 micron) spectroscopic population study of asteroids and comets to study their surface composition and monitor activity. Its wavelength coverage and position above the atmosphere will make it particularly well-suited for studying hydration features that are obscured by telluric lines from the ground as well as searching for other spectral signatures such as organics, silicates and CO&lt;sub&gt;2&lt;/sub&gt;.&lt;/p&gt; &lt;p&gt;I will present an overview of Twinkle&amp;#8217;s capabilities and discuss the broad range of targets the mission could observe, including the measurements it will take to support&amp;#160;&lt;span class=&quot;size&quot;&gt;JAXA's Martian Moons&amp;#160;eXploration&amp;#160;(MMX) mission, demonstrating the broad scientific potential of the spacecraft.&lt;/span&gt;&lt;/p&gt;

Radiation field of cosmic rays measured in low Earth orbit by CR-39 detectors

2006 ◽  
Vol 37 (9) ◽  
pp. 1764-1769 ◽  
Author(s):  
D. Zhou ◽  
D. O’Sullivan ◽  
E. Semones ◽  
W. Heinrich
Keyword(s):  
Cosmic Rays ◽  
Radiation Field ◽  
Low Earth Orbit ◽  
Earth Orbit ◽  
Cr 39 Detectors

scholarly journals Observations of the Near-Infrared Extragalactic Background Light

2001 ◽  
Vol 204 ◽  
pp. 87-100
Author(s):  
Toshio Matsumoto
Keyword(s):  
Large Scale ◽  
Near Infrared ◽  
High Redshift ◽  
Far Infrared ◽  
Zodiacal Light ◽  
Extragalactic Background Light ◽  
Background Light ◽  
Infrared Telescope ◽  
Total Energy Flux ◽  
Infrared Spectrometer

We searched for the near infrared extragalactic background light (IREBL) in data from the Near Infrared Spectrometer (NIRS) on the Infrared Telescope in Space (IRTS). After subtracting the contribution of faint stars and a modeled zodiacal component, a significant isotropic emission is detected whose in-band flux amounts to ~ 30 nWm−2sr−1. This brightness is consistent with upper limits of COBE/DIRBE, but is significantly brighter than the integrated light of faint galaxies. The star subtraction analyses from DIRBE data show essentially the same results apart from the uncertainty in the model of the zodiacal light. A significant fluctuation of the sky brightness was also detected. A 2-point correlation analysis indicates that the fluctuations have a characteristic spatial structure of 100 ~ 200 arcmin. This could be an indication of the large scale structure at high redshift. Combined with the far infrared and submillimeter EBL, the total energy flux amounts to 50 ~ 80 nWm−2sr−1 which is so bright that unknown energy sources at high redshifts are required.

scholarly journals Large angular scale fluctuations of near-infrared extragalactic background light based on the IRTS observations

2019 ◽  
Vol 71 (4) ◽  
Author(s):  
Min Gyu Kim ◽  
Toshio Matsumoto ◽  
Hyung Mok Lee ◽  
Woong-Seob Jeong ◽  
Kohji Tsumura ◽  
...  
Keyword(s):  
Large Scale ◽  
Near Infrared ◽  
High Redshift ◽  
Zodiacal Light ◽  
Extragalactic Background Light ◽  
Background Light ◽  
Normal Galaxies ◽  
Infrared Telescope ◽  
Angular Scale ◽  
Using Data

Abstract We measure the spatial fluctuations of the Near-Infrared Extragalactic Background Light (NIREBL) from 2° to 20° in angular scale at the 1.6 and $2.2\, \mu \mathrm{m}$ using data obtained with Near-Infrared Spectrometer (NIRS) on board the Infrared Telescope in Space (IRTS). The brightness of the NIREBL is estimated by subtracting foreground components such as zodiacal light, diffuse Galactic light, and integrated star light from the observed sky. The foreground components are estimated using well-established models and archive data. The NIREBL fluctuations for the 1.6 and $2.2\, \mu \mathrm{m}$ connect well toward the sub-degree scale measurements from previous studies. Overall, the fluctuations show a wide bump with a center at around 1° and the power decreases toward larger angular scales with nearly a single power-law spectrum (i.e., ${F[\sqrt{l(l+1)C_l/2\pi }]} \sim \theta ^{-1}]$, indicating that the large-scale power is dominated by the random spatial distribution of the sources. After examining several known sources, contributors such as normal galaxies, high-redshift objects, intra-halo light, and far-IR cosmic background, we conclude that the excess fluctuation at around the 1° scale cannot be explained by any of them.

Sign in / Sign up

Export Citation Format

Share Document