Share This Page

Astronomers find blue planet outside solar system

| Friday, July 12, 2013, 8:51 p.m.

LONDON — Astronomers for the first time have managed to determine the color of a planet outside our solar system, a blue gas giant 63 light-years away.

Using the Hubble Space Telescope, an international team said the planet known as HD 189733B would look like a deep blue dot if viewed up-close.

“Measuring the planet's color is a real first — we have never managed it before with a planet outside our own solar system,” Frederic Pont of the University of Exeter in England said on Friday.

While Earth looks blue from space because of its oceans, the astronomers said the planet's color was formed by a hazy turbulent atmosphere of silicate particles that scatter blue light. To determine the planet's color, the team measured the amount of light reflected off its surface as it passed behind its star.

Discovered in 2005, the planet belongs to a class of giant gas planets called “hot Jupiters” that orbit close to their stars. It has a daytime temperature of around 1,832 degrees, and the heat causes rocks to evaporate and glass to possibly rain sideways in howling 4,500-mph wind.

Astronomers chose the planet for observation because of its proximity to Earth and size in relation to the star it orbits. A light-year is nearly 6 trillion miles.

Pont said the technology the astronomers used pushed the Hubble telescope to its limit given the distance and light from other stars obscuring their view.

“People keep coming up with a better way of viewing planets indirectly, so I'm sure the technology will eventually improve,” Pont said.

TribLIVE commenting policy

You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.

We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.

While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.

We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers

We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.

We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.

We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.

We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.