Partly for this reason, space telescopes like Hubble can observe much fainter objects than current ground-based telescopes at visible wavelengths.
Karena alasan ini, teleskop ruang angkasa seperti teleskop ruang angkasa Hubble dapat melihat lebih banyak objek samar-samar dibandingkan dengan teleskop bumi pada gelombang cahaya tampak.
Airglow at night may be bright enough for a ground observer to notice and appears generally bluish.
Pijaran udara di malam hari mungkin cukup terang untuk dilihat oleh pengamat, dan umumnya berwarna kebiru-biruan.
Although airglow emission is fairly uniform across the atmosphere, it appears brightest at about 10° above the observer's horizon, since the lower one looks, the greater the mass of atmosphere one is looking through.
Meskipun emisi pijaran udara sangat seragam di atmosfer, bagi pengamat di lapangan ia akan tampak paling terang sekitar 10 derajat di atas cakrawala, karena semakin rendah seseorang melihat semakin dalam atmosfer yang dapat terlihat.
One airglow mechanism is when an atom of nitrogen combines with an atom of oxygen to form a molecule of nitric oxide (NO).
Salah satu mekanisme yang menghasilkan pijaran udara terjadi ketika sebuah atom nitrogen bergabung dengan atom oksigen untuk membentuk molekul nitrit oksida (NO).
In the process, a photon is emitted.
Dalam prosesnya foton dipancarkan.
This photon may have any of several different wavelengths characteristic of nitric oxide molecules.
Photon ini memiliki beberapa karakteristik panjang gelombang yang berbeda dari molekul nitrit oksida.
The free atoms are available for this process, because molecules of nitrogen (N2) and oxygen (O2) are dissociated by solar energy in the upper reaches of the atmosphere and may encounter each other to form NO.
Atom bebas tersedia untuk proses ini karena molekul-molekul nitrogen (N2) dan oksigen (O2) terpisah oleh tenaga surya di bagian atas atmosfer, dan mungkin bertemu satu sama lain untuk membentuk NO.
At visible wavelengths, we need the parameter S0(V), the power per square centimetre of aperture and per micrometre of wavelength produced by a zeroth-magnitude star, to convert apparent magnitudes into fluxes – S0(V)4.0×10−12 W⋅cm−2⋅µm−1.
Pada panjang gelombang tampak kita memerlukan parameter S0(V), daya per sentimeter persegi dari celah dan per mikrometer dari panjang gelombang yang dihasilkan oleh bintang dengan besar nol, untuk mengubah besaran terlihat (apparent magnitude) menjadi fluks -- S 0 ( V )
If we take the example of a V28 star observed through a normal V band filter (B0.2 μm bandpass, frequency ν ≈ 6×1014 Hz), the number of photons we receive per square centimeter of telescope aperture per second from the source is Ns: N s10 − 28 / 2.5 × S 0 ( V ) × B h ν }=10^{-28/2.5}\times {\frac {S_{0}(V)\times B}{h\nu }}} (where h is the Planck constant; hν is the energy of a single photon of frequency ν).
Jika kita mengambil contoh V=28 bintang terlihat melalui suatu V tapis pita (band filter) normal ( B0.2 µm lolos-pita, frekuensi ν ∼ 6 × 10 14 } Hz), jumlah foton yang kita terima per meter persegi dari suatu celah teleskop per detik dari sumbernya adalah N s } : N s10 − 28 / 2.5 × S 0 ( V )
This gives the number of photons from airglow, Na: N a10 − 23 / 2.5 × S 0 ( V ) × B h ν }=10^{-23/2.5}\times {\frac {S_{0}(V)\times B}{h\nu }}} The signal-to-noise for an ideal ground-based observation with a telescope of area A (ignoring losses and detector noise), arising from Poisson statistics, is only: S / NA × N s N s + N a }\times {\frac {N_{\text{s}}}{\sqrt {N_{\text{s}}+N_{\text{a}}}}}} If we assume a 10 m diameter ideal ground-based telescope and an unresolved star: every second, over a patch the size of the seeing-enlarged image of the star, 35 photons arrive from the star and 3500 from air-glow.
Jadi jumlah foton dari pijaran udara, N a } : N a10 − 23 / 2.5 × S 0 ( V ) × B h ν10^{-23/2.5}\times {\frac {S_{0}(V)\times B}{h\nu }}} Sinyal-derau dari suatu pengamatan di bumi dengan suatu teleskop dengan luas A (dengan mengabaikan rugi-rugi dan derau pada detektor), dengan menggunakan statistik distribusi Poisson, adalah: S / NA × N s N s + N a }\times {\frac {N_{s}}{\sqrt {N_{s}+N_{a}}}}} Percobaan ilmiah telah dilakukan untuk mengimbas (to induce) pijaran udara dengan mengarahkan emisi radio daya tinggi pada bumi ionosfer.
Earthlight Ionized-air glow Optical phenomena Polar aurora Zodiacal light Description and Images Sky Brightness Information for Roque de los Muchachos Observatory Night-side Glow Detected at Mars Space.com interview Stereoscopic Observations of HAARP Glows from HIPAS, Poker Flat, and Nenana, Alaska by R.F. Wuerker et al.
Description and Images Sky Brightness Information untuk Observatorium Roque de los Muchachos Night-side Glow Detected at Mars Space.com interview Stereoscopic Observations of HAARP Glows from HIPAS, Poker Flat, and Nenana, Alaska by R.F. Wuerker et Al.
An improved signal-to-noise ratio of a cool imaging photon detector for Fabry - Perot interferometer measurements of low-intensity air glow by T P Davies and P L Dyson Space Telescope Imaging Spectrograph Instrument Handbook for Cycle 13 SwissCube|
An improved signal-to-noise ratio of a cool imaging photon detector for Fabry - Perot interferometer measurements of low-intensity air glow by T P Davies and P L Dyson Space Telescope Imaging Spectrograph Instrument Handbook for Cycle 13