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Hubble Space Telescope Hubble Space Telescope (Spacetelescope.Org) Molly Rose Guiyun Merkert, Colorado College the Release of the HST on April 24, 1990

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Hubble Space Telescope Hubble Space Telescope (Spacetelescope.Org) Molly Rose Guiyun Merkert, Colorado College the Release of the HST on April 24, 1990 Hubble Space Telescope Hubble Space Telescope (spacetelescope.org) Molly Rose Guiyun Merkert, Colorado College The release of the HST on April 24, 1990. The Hubble Space Telescope Background Discoveries ● Agencies: NASA, ESA, & STScI There are two types of optical telescopes: refracting telescopes Over the past 29 years, the Hubble Space Telescope has observed ● Launch: April 24, 1990 (uses lenses) and reflecting telescopes (uses mirrors). Refracting known objects in higher detail and has been used to confirm ● Size: 43.5 ft x 14 ft x 40 ft telescopes can be affected by to chromatic aberration (where theories (like the existence of black holes). It has also been used ● Weight: 24,500 pounds light of different wavelengths focus at different locations). This to research cosmology, dark matter, gravitational lensing, and ● Ritchey-Chretien Cassegrain HST Design (The Hubble Wars) does not happen in reflecting telescopes. cosmic expansion. The Hubble Space Telescope has also An image of the Ritchey-Chretien discovered so many space objects, especially through its deep ● Primary Mirror: 94.5” diameter Cassegrain optical design Observations from Earth based telescopes are often impeded by field images. clouds, light pollution, and astronomical seeing (unpredictable Primary Mirror Problem changes in the atmosphere that bend light going through it). A flaw in the telescope’s primary mirror caused the light focus at different places, causing a halo to appear around objects. Diffraction patterns are created when a point light source (like a laser or star) illuminates a sharp edged object. Hubble Deep Field (spacetelescope.org) aXtreme Deep Field (nasa.gov) Approximately 27 million galaxies can A more recent deep field image from be seen in this image from a seemingly 2012 empty section of space. Taken in 1995. Mirror Flaw (The Hubble Wars) Strange Halo (spacetelescope.org) The primary mirror was only 2 microns The halo around 30 doradus is caused HST Pattern (iopscience.iop.org) Diffraction Patterns (britannica.com) too flat at the edges. by the problem in the primary mirror. What the diffraction pattern from An image explaining why diffraction The Future Hubble Space Telescope’s aperture patterns occur. The Hubble Space Telescope will stop functioning. The telescope COSTAR and Tiny Tim should look like slowly loses altitude each year as well; eventually it will fall to To solve the problems with telescope’s mirror, COSTAR was Earth. However before that, the gyroscopes that are used to installed in December 1993. This arrangement of five mirrors How good is Hubble? point the telescope will wear out. bent the light rays to focus at the same place. COSTAR was We can measure how good a telescope is by using the Rayleigh removed in 2009. Criterion. It gives the angle needed between two light sources However, in the future, the James Webb Space Telescope will be (or stars in this case) for the two sources to be seen as separate sent to space and the European Extra Large Telescope will use M100 (spacetelescope.org) objects. For telescopes, this is given by: lasic adaptive optics to counter astronomical seeing. Left: An image taken by the Hubble Space Telescope where Ө is the angle (in radians) between the two stars, λ is the Right: The same object taken wavelength of the light, and D is the diameter of the primary Acknowledgments with COSTAR installed. mirror. Special thanks to Professor Shane Burns and Professor Stephanie DiCenzo A computer program called Tiny Tim is used to determine star “About the James Webb Space Telescope.” NASA, NASA, jwst.nasa.gov/about.html. For the Hubble Space Telescope (with COSTAR), this angle is 0.05 diffraction patterns. If an object deviates too much from this Burns, Shane. A Practical Guide to Observational Astronomy. 2017. arcseconds. An Earth bound telescope has a limiting resolution of pattern, it is probably not a star. Chaisson, Eric J. The Hubble Wars: Astrophysics Meets Astropolitics in the Two-Billion-Dollar Struggle over the about 1 arcsecond under optimal conditions. Hubble Space Telescope. Harvard University Press, 1998. Chromey, Frederick R. To Measure the Sky: an Introduction to Observational Astronomy. Cambridge University Press, 2010. F1042M Diffraction Patterns Globular Star Cluster M-14 Giancoli, Douglas C. Physics for Scientists & Engineers with Modern Physics. Pearson, 2009. (stsci.edu) (spacetelescope.org) “Hubble's Top Breakthroughs.” HubbleSite - Hubble Breakthroughs - Home, NASA, Left: An image taken by the Left: 4-meter telescope at Cerro hubblesite.org/hubble_discoveries/breakthroughs/. Hubble Space Telescope Tololo Inter-American Observatory Petersen, Carolyn Collins., and John C. Brandt. Hubble Vision: Astronomy with the Hubble Space Telescope. Right: The diffraction pattern has a resolution of 1.5 arcseconds Second ed., Cambridge University Press, 1998. created by Tiny Tim Right: Faint object camera has a Sparrow, Giles. Hubble: Legacy Edition. Quercus, 2014. resolution of 0.08 arcseconds [email protected]. “The European ELT.” ESO, www.eso.org/sci/facilities/eelt/..
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