Home » News & Blogs » Making Hubble's Color Image of Comet ISON
Bookmark and Share
ISONblog

Making Hubble's Color Image of Comet ISON

25 Jul 2013, 12:00 UTC
Making Hubble's Color Image of Comet ISON
(200 words excerpt, click title or image to see full post)

Taking a picture with the Hubble Space Telescope isn't quite like taking a picture with a point-and-shoot camera. The cameras on the telescope don't produce color images automatically, but make black-and-white images through color filters. Color images are assembled from a number of exposures taken during Hubble orbit around the Earth.

The color image of Comet ISON described in a previous blog post is a composite of five exposures taken on April 30, 2013. All of the images were made with the Wide Field Camera 3 UVIS instrument (WFC3/UVIS) during one orbit of Hubble around the Earth. Three exposures of 440 seconds each were made using the V band filter (technically known as F606W), which transmits yellow/green light, and two exposures of 490 seconds each in the I band filter (F814W) which transmits red and some near infrared light.

These exposures were made while the telescope tracked the stars. Because of the motion of the comet and the motion of HST in its orbit around the Earth, the comet trailed slightly relative to the stars during and between these exposures. This is not the way comets are usually observed. Normally we would track on the comet to keep ...

Latest Vodcast

Latest Podcast

Advertise PTTU

NASA Picture of the Day

Astronomy Picture of the Day

astronomy_pod