Skip to main content

Unsettled Youth: Spitzer Observes a Chaotic Planetary System



Before our planets found their way to the stable orbits they circle in today, they wiggled and jostled about like unsettled children. Now, NASA's Spitzer Space Telescope has found a young star with evidence for the same kind of orbital hyperactivity. Young planets circling the star are thought to be disturbing smaller comet-like bodies, causing them to collide and kick up a huge halo of dust.

The star, called HR 8799, was in the news last November 2008, for being one of the first of two stars with imaged planets. Ground-based telescopes at the W.M. Keck Observatory and the Gemini Observatory, both in Hawaii, took images of three planets orbiting in the far reaches of the system, all three being roughly 10 times the mass of Jupiter. Another imaged planet was also announced at the same time around the star Fomalhaut, as seen by NASA's Hubble Space Telescope. Both HR 8799 and Fomalhaut are younger and more massive than our sun.

Astronomers had previously used both Spitzer and Hubble to image a rotating disk of planetary debris around Fomalhaut, which is 25 light-years from Earth. HR 8799 is about five times farther away, so scientists weren't sure if Spitzer would be able to capture a picture of its disk. To their amazement and delight, Spitzer succeeded. The picture can be seen online at http://spitzer.caltech.edu/images/2781.

The Spitzer team, led by Kate Su of the University of Arizona, Tucson, says the giant cloud of fine dust around the disk is very unusual. They say this dust must be coming from collisions among small bodies similar to the comets or icy bodies that make up today's Kuiper Belt objects in our solar system. The gravity of the three large planets is throwing the smaller bodies off course, causing them to migrate around and collide with each other. Astronomers think the three planets might have yet to reach their final stable orbits, so more violence could be in store.

"The system is very chaotic and collisions are spraying up a huge cloud of fine dust," said Su. "What's exciting is that we have a direct link between a planetary disk and imaged planets. We've been studying disks for a long time, but this star and Fomalhaut are the only two examples of systems where we can study the relationships between the locations of planets and the disks."

When our solar system was young, it went through similar planet migrations. Jupiter and Saturn moved around quite a bit, throwing comets around, sometimes into Earth. Some say the most extreme part of this phase, called the late heavy bombardment, explains how our planet got water. Wet, snowball-like comets are thought to have crashed into Earth, delivering life's favorite liquid.

The Spitzer results were published in the Nov. 1 issue of Astrophysical Journal. The observations were made before Spitzer began its "warm" mission and used up its liquid coolant.

Tags : Space Shuttle, News in Nasa, Current Nasa News, Nasa Daily News, Nasa News Today, Jet Propulsion Laboratory, JPL, NASA, International Space Station, NASA's Jet

Comments

Popular posts from this blog

Kerala boat tragedy: Thirty five bodies have been fished out of the water

THEKKADY / KOCHI: A thick veil of grief descended on the famed tourist spot of Thekkady on Wednesday when Kerala witnessed its worst ever boat tragedy in the Mullaperiyar waters as the KTDC’s Jalakanyaka, carrying about 76 passengers, sank. Thirty five bodies have been fished out of the water. Any hope of finding more tourists alive faded with the daylight even as rescue personnel continued their desperate search. The two-deck boat, commissioned just a month back, was returning to the boat landing after an hour-long sight-seeing trip when tragedy struck. All the passengers on the upper deck apparently rushed to one side of the boat to take photos of a lone bison spotted on the shore. At the same time many from the lower deck flocked to the top leaving the lower almost empty. This movement and the uneven distribution of weight caused the boat to overbalance and turn turtle. Those remaining on the lower deck were trapped inside while about 20 on the upper deck were rescued by other boa

Special Status For Jammu & Kashmir Scraped: 5 Points About Article 370

Jammu & Kashmir will also be "reorganized," Home Minister Amit Shah said as talks about the state being trifurcated into three separate fields- Jammu, Kashmir and Ladakh NEW DELHI: Article 370, which gives Jammu & Kashmir unique status, will be withdrawn this morning in parliament, Home Minister Amit Shah said . The announcement came after his cabinet meeting at his house this morning was held by Prime Minister Narendra Modi . Article 370 is a ' temporary provision ' granting special autonomous status to Jammu & Kashmir . It allows the state to draft its own Constitution and restricts the legislative powers of the parliament over the state. The government therefore requires state government approval for all legislation, except those related to defence, foreign affairs, finance, and communications. Parliament can not also improve or decrease the boundaries of the State under Article 370 As a consequence, citizens of Jammu & Kashmir

Enai Nokki Paayum Thotta Movie Review: Tiring and Unsatisfying

Movie Rating: 3/5 First of all things! The director's weakest film is the long delayed Enai Noki Paayum Thotta by Gautham Menon . The film's main weakness is the director's fascination with narrative style voice-over. It was good before Gautham used voice-over as a medium to tell his stories, but every scene in Enai Nokki Paayum Thotta begins and ends with Dhanush's voice-over, which irritates us after a point. The film is filled with tired stereotypes, and at a runtime of 157 minutes it is an unsatisfying watch. Like any other movie from Gautham Menon, here too hero Raghu (Dhanush) is a student of engineering, but this time his wife is not a student, but a film heroine Lekha ( Mega Akash ).She tells him she is not interested in movies and her boss Kuberan (Senthil Veeraswamy) coerced her into the profession for money (it looks like the girl is an orphan and Kuberan supported her studies and is her guardian). Raghu takes her to his Pollachi house and introduc