Discover and read the best of Twitter Threads about #HST
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À gauche, l'amas de galaxie SMACS 0723 vue par Hubble #HST
À droite, la première image officielle du télescope spatial James Webb #JWST
Oui on est sur une sacrée amélioration !
#UnfoldTheUniverse
@NASAWebb
À droite, la première image officielle du télescope spatial James Webb #JWST
Oui on est sur une sacrée amélioration !
#UnfoldTheUniverse
@NASAWebb
L'amas de galaxie #smacs0723 est à une distance de 4,7 milliards d'années-lumière mais sa particularité c'est de servir de lentille gravitationnelle pour magnifier la lumière des galaxies aux confins de l'univers observable qui se trouvent derrière, grossies mais déformées
#JWST
#JWST
Certains n'ont pas chômé pendant la nuit ! (ou peut-être un fuseau horaire plus avantageux 😅)
En tout cas ces comparaisons sont impressionnantes
En tout cas ces comparaisons sont impressionnantes
Where does #JWST reside on the spectrum of telescopes? The EM spectrum ranges for various space-based telescopes and a few ground telescopes are shown below. JWST observes in the 0.6–28.3 μm wavelength range (orange to mid-infrared). Hubble ST observes in the 0.1–1.0 μm range.
The Herschel Space Observatory, active from 2009 to 2013, observed in the far IR 55-672 µm range, from its perch at L2 (same as #JWST!). Its 3.5 m mirror was made of sintered silicon carbide. Detectors were kept at temps below 2 deg K, using 2,300 litres of liquid helium at 1.4 K
The Spitzer Space Telescope, 2003-2020, observed in the infrared 3.6-160 µm range from an Earth-trailing orbit. Its 0.85 m Beryllium mirror and detectors were kept at near zero temps using liquid helium. The LHE depleted in 2009, limiting Spitzer to shorter wavelengths.
Bored while waiting for #jwst's mirrors to open tomorrow? Let's have a small technical chat about the optical design in the mean time. 1/n 🧵
webb.nasa.gov/content/observ…
webb.nasa.gov/content/observ…
If you didn't know, #jwst is a three mirror anastigmat telescope that works slightly off-axis. A couple very interesting notes:
1) It has an effective vocal length of 131 meters!
2) The primary mirror is concave and the secondary mirror is convex.
2/n
1) It has an effective vocal length of 131 meters!
2) The primary mirror is concave and the secondary mirror is convex.
2/n
What drives this design? It's all about the individual pixels on the sensors. These are finite in size (~18 microns) for both scientific and technological reasons. We'll learn more about detectors later. 3/n
31. The Legacy of US, UK, France, Israel, Saudi Arabia, Turkey, Bahrain, Canada, Qatar, United Arab Emirates, Germany, Belgium, Netherlands, Australia, Jordan, Nato in Syria
#RegimeChange #FakeNews #FalseFlag #terrorism #SyriaInvasion #WarCrimes #CrimesAgainstHumanity
#RegimeChange #FakeNews #FalseFlag #terrorism #SyriaInvasion #WarCrimes #CrimesAgainstHumanity
1 to 20. The Legacy of US, UK, France, Israel, Saudi Arabia, Turkey, Bahrain, Canada, Qatar, United Arab Emirates, Germany, Belgium, Netherlands, Australia, Jordan, Nato in Syria 🤨👇🏼
threadreaderapp.com/thread/1136642…
threadreaderapp.com/thread/1136642…
21. The Legacy of US, UK, France, Israel, Saudi Arabia, Turkey, Bahrain, Canada, Qatar, United Arab Emirates, Germany, Belgium, Netherlands, Australia, Jordan, Nato in Syria🤨👇🏼
threadreaderapp.com/thread/1137566…
threadreaderapp.com/thread/1137566…
