Why not just pick a few interesting objects out there in space and actually look at some comparable images? Nancy Atkinson over at Universe Today already did that for some Hubble targets, though she didn't specify which cameras the before and after images came from. the NIRI imager with ALTAIR adaptive optics system at Gemini North Observatory, also on Mauna Kea.NaCo on the Very Large Telescope (VLT) at Cerro Paranal, Chile and.NIRC2 on the Keck II telescope on Mauna Kea, Hawaii.Ideally you'd like to maximize field of view and minimize pixel size. (For comparison, the Moon at 30 arcminutes or 1800 arcseconds across would be about twice the width of the whole diagram.) The bottom row (below the dashed line) compares pixel sizes. The top row (above the dashed line) compares fields of view - how much of the sky each one takes in. I came up with the following diagram that compares the capabilities of the different instruments. I spent a couple of hours this morning noodling around the Space Telescope Science Institute website reading instrument descriptions. (So it's a good thing that they're now reporting progress on getting NICMOS' cooling system working again.) And although Earth-based instruments at the Keck, VLT, and Gemini observatories can beat Hubble resolution using adaptive optics, that's only at near-infrared wavelengths shorter than 800 nanometers (and especially in the ultraviolet) there's nothing on Earth that can get sharper images than Hubble. It improves marginally on the resolution of the largest-field-of-view optical images that Hubble was capable of before (ACS Wide Field camera), and it really beats the pants off of the field of view of NICMOS, though at lower resolution than NICMOS can manage. It's an improvement on WFPC2 in almost every way. Here's the executive summary: what WFC3 brings to the party is a killer combination of large field of view and pretty high resolution. the newly-installed Wide Field Camera 3 (WFC3), which replaced WFPC2 in May 2009 and was also intended to largely supplant NICMOS.the Advanced Camera for Surveys (ACS), an ultraviolet- to very near-infrared imager, in use since 2002 but with a hiccup in 2007, mostly repaired in May 2009 and.the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS), a near-infrared imager, installed in 1997, which has had periodic problems with its cooling system and was most recently offline from November 2008 to August 2009.The Wide Field and Planetary Camera 2 (WFPC2), an ultraviolet- to very near-infrared imager, Hubble's workhorse from 1993 to 2009.There's four main Hubble instruments I was interested in comparing with each other and to Earth: Last week when the new, post-servicing-mission-4 capabilities of Hubble were unveiled, I kept asking myself: How do Hubble's new capabilities compare to what it could do before the servicing mission, and how do they compare to what we can do from the ground? I fired off some questions to Heidi Hammel, and did some research on my own within the Hubble instrument description documents. And once on the Earth again I hope to have the opportunity to bring it back to the Museo di Storia della Scienza in Florence.Apologies in advance for the number of acronyms in this post. “I hope to be able to bring it outside the Shuttle with me and use it for watching the stars. “Bringing Galileo’s telescope into the space is a way to honour my origin,” Massimino declared. The honour of bringing Galileo’s telescope into orbit is committed to veteran spacewalker of Italian origin, Michael “Mike” Massimino. This emblematic event marks NASA’s contribution to international celebrations of the Tuscan scientist in the four-hundredth anniversary of his first celestial discoveries, in collaboration with the Istituto e Museo di Storia della Scienza. Galileo succeeded in seeing mountains and craters of the Moon, the orbiting telescope is able to reach even the hypothetical boundaries of the universe. On the contrary, the difference between the magnifying power of the two telescopes is much bigger: not only 1 to 150, but 1 to one million. While the telescope made by Galileo has a lens opening of 1.5 centimetres, Hubble’s mirror lens is 2.4 metres in diameter, that is over 150 times bigger. The instrument that 400 years ago dramatically changed the idea of the universe will be side-by-side with a treasure of contemporary astronomy. The shuttle took off on Monday, May 11 from the Kennedy Space Center at Cape Canaveral for a 11-day mission aimed at repairing and updating Hubble, the renowned orbiting telescope. A replica of Galileo’s telescope, provided by the Istituto e Museo di Storia della Scienza, has been launched into the space aboard the shuttle Atlantis STS 125.
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