Featured Research

from universities, journals, and other organizations

Longstanding Astronomical Puzzle Solved

Date:
May 31, 2007
Source:
Dartmouth University
Summary:
A team of astronomers has recalculated the explosion date of the famous Crab Nebula supernova and found excellent agreement between their measurements and the classic date of the 1054 A.D. appearance of a bright "guest star" seen in the constellation of Taurus the Bull.

A magnified green-light image of the northern jet taken with the Subaru 8.2 meter telescope in October 2005.
Credit: Toru Yamada/NAOJ

A team of astronomers has recalculated the explosion date of the famous Crab Nebula supernova and found excellent agreement between their measurements and the classic date of the 1054 A.D. appearance of a bright "guest star" seen in the constellation of Taurus the Bull.

The research was led by Gwen Rudie, a senior physics major at Dartmouth. She and her adviser, Robert Fesen, along with Toru Yamada from Japan's Subaru Observatory in Hawaii, used photographs taken 17 years apart to study the expansion speed of the Crab Nebula, in results released May 29 in Honolulu at the 210th meeting of the American Astronomical Society.

These astronomers found that the outermost part of the supernova remnant, a very faint "jet" of stellar debris, shows clearly for the first time that the Crab exploded around the middle of the 11th century, in perfect accord with historic records. "For the past 100 years astronomers have puzzled over the discrepancy between the measured age of the Crab Nebula versus the age suggested by numerous historical sightings around the ancient world," Rudie said. "This work verifies some long-standing assumptions about the nature of the Crab-with our result, science and history finally agree."

The Crab Nebula is one of the most studied remains of a stellar explosion and is widely accepted to be due to a supernova seen in the year 1054 A.D. by Chinese, Japanese, Korean, and Arab astronomers, who reported sighting a new bright star in the heavens. The star was so brilliant that it was visible even during the day for nearly three weeks and only faded from view nearly two years later.

While the Crab Nebula's location in the sky agreed very well with the reported position of this bright new star, several studies of the expanding cloud of stellar debris unexpectedly indicated that it was expanding much too fast to be associated with a supernova explosion in 1054. Instead, these studies pointed later in time, toward an explosion date in the first half of the 12th century.

This dilemma led astronomers to the idea that the remnant's central pulsar—the rapidly spinning and extremely dense neutron star left over from Crab's supernova explosion—emitted such copious amounts of energy that it actually accelerated the expanding cloud of debris, making it move faster with time.

"Previous studies have focused on the main body of the Crab Nebula, which has been accelerated with time," Rudie explained. "We chose to look at the northern jet because it is father from the pulsar. That was the key to our new age determination."

The images used in this study were taken 17 years apart: one in October 2005 with the Prime Focus Camera (Suprime-Cam) on the Subaru 8.2-meter telescope on Mauna Kea by astronomers from the National Astronomical Observatory of Japan, Tohoku University, and Kyoto University, and one taken with t he National Science Foundation's Mayall 4-meter telescope at Kitt Peak National Observatory, part of the National Optical Astronomy Observatory, Tucson, Arizona, by Robert Fesen of Dartmouth in November 1988.

The new Subaru image used in the study was released in March 2007 as an image-only. The new results pertain to a scientific study of the movement of the supernova debris across the plane of the sky. By measuring this proper motion over the course of 17 years and tracing it backward in time, this group of astronomers was able to confirm the 1054 explosion date.


Story Source:

The above story is based on materials provided by Dartmouth University. Note: Materials may be edited for content and length.


Cite This Page:

Dartmouth University. "Longstanding Astronomical Puzzle Solved." ScienceDaily. ScienceDaily, 31 May 2007. <www.sciencedaily.com/releases/2007/05/070530184432.htm>.
Dartmouth University. (2007, May 31). Longstanding Astronomical Puzzle Solved. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2007/05/070530184432.htm
Dartmouth University. "Longstanding Astronomical Puzzle Solved." ScienceDaily. www.sciencedaily.com/releases/2007/05/070530184432.htm (accessed July 25, 2014).

Share This




More Space & Time News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: ISS Cargo Ship Launches in Kazakhstan

Raw: ISS Cargo Ship Launches in Kazakhstan

AP (July 23, 2014) The Progress 56 cargo ship launched from the Baikonur Cosmodrome in Kazakhstan Wednesday. NASA says it will deliver cargo and crew supplies to the International Space Station. (July 23) Video provided by AP
Powered by NewsLook.com
Raw: Cargo Craft Undocks from Space Station

Raw: Cargo Craft Undocks from Space Station

AP (July 22, 2014) A Russian Soyuz cargo-carrying spacecraft undocked from the International Space Station on Monday. The craft is due to undergo about ten days of engineering tests before it burns up in the Earth's atmosphere. (July 22) Video provided by AP
Powered by NewsLook.com
NASA Ceremony Honors Moon Walker Neil Armstrong

NASA Ceremony Honors Moon Walker Neil Armstrong

AP (July 21, 2014) NASA honored one of its most famous astronauts Monday by renaming a historic building at the Kennedy Space Center in Florida. It now bears the name of Neil Armstrong, the first man to walk on the moon. (July 21) Video provided by AP
Powered by NewsLook.com
Neil Armstrong's Post-Apollo 11 Life

Neil Armstrong's Post-Apollo 11 Life

Newsy (July 19, 2014) Neil Armstrong gained international fame after becoming the first man to walk on the moon in 1969. But what was his life like after the historic trip? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins