Playing Detective: Birth of New Star Provides Clues about Origin of the Solar System
On the night of January 23, 2004, Jay McNeil was in his backyard in Kentucky staring at the stars with his small telescope, as he had each night for years. While he watched, the patch of sky right next to the well-known gas cloud Messier 78 suddenly flared. McNeil, an amateur astronomer, had witnessed the birth of a star, a sight recorded by only two astronomers during the past century.
Intrigued with this new sight, McNeil contacted both star formation expert Bo Reipurth and Lowell Observatory. Within a few hours, follow-up observations were being made with the large telescope at the University of Hawaii as well as with the giant 8-meter Gemini telescope, also in Hawaii.
"The idea that this thing, first seen on my 3-inch telescope, which one can easily hold using one hand, would be observed, within 48 hours, by a telescope of 342 tons was absolutely staggering," McNeil commented in his interview with BBC News.
The star spotted by McNeil was born in a region where new stars flare, or flash brightly, about 100 million times over a period of a few months and then fade away. McNeil had watched the star bursting out of its placental nebula, the cloudlike mass of matter situated around the star. The star's flaring lit up the surrounding McNeil Nebula, allowing astronomers to look inside the nebula. By piecing together views of the sky taken automatically by telescopes over the past year, astronomers have concluded that the star was first visible last November.
The star, now known as V1647 Ori, is one of the youngest ever studied less than a million years old, compared to the average star's age of 100 million years. It is also about the same mass as the sun, which is unusual for its young age. With the recent improvements in telescope technology, the evolution of V1647 Ori can be monitored with much greater accuracy and detail than any previous star has been.
After the star's discovery, David Weintraub of Vanderbilt University and Joel Kastner of Rochester Institute of Technology submitted emergency requests for viewing time on the orbiting Chandra X-ray Observatory. The two scientists chose to use the Chandray X-ray Observatory because X-rays are released during extremely violent natural events, and the flares of V1647 Ori could be more closely observed by looking at the X-ray release pattern.
Weintraub and Kastner observed V1647 Ori in March. They found that the star released more X-rays in early March while it was bright, and it released fewer X-rays in late March when it was fading. Ted Gibson in Hawaii also found that the X-ray strength was directly correlated with the flaring of the star.
Currently, scientists think that X-ray production from stars is dependent on how fast the star spins and how fast heat energy is leaving the star.
However, the X-rays produced from V1647 Ori are much stronger than expected. Weintraub and Kastner have proposed that V1647 Ori contains a small disk around it made of gas and dust leftover from the star's formation. From this disk, planets may form. Flares of V1647 Ori may then occur because pieces of the disk's material fall onto the surface of the star, resulting in much more intense X-rays.
"The X-rays are produced and the magnetic field of the star gets tangled up with the magnetic field of the disk. Those two magnetic fields act like two ropes that get tangled up and twisted up, and the star is rotating faster than the disk is revolving. So those ropes get twisted and twisted and twisted until they snap," Weintraub explains, indicating how the protoplanetary disk may form into a planet.
If Weintraub and Kastner's hypothesis is valid, X-ray observation may help distinguish planets that have protoplanetary disks from those that do not. This hypothesis would also lead to improved theories about the formation of planets.
Jay McNeil's nightly study of the sky has led to a new hypothesis about the formation of our solar system. McNeil remains quite excited about his discovery, especially since he is an amateur astronomer and is one of millions of people who scan the skies nightly.
"I have spent countless hours seeking out the darkest of skies and peering into the largest of telescopes at distant galaxies," remarks McNeil. "So who would have known that I would take an image of a famous object with a small telescope from my back yard and find a sun-like star being born."
Jay McNeil's Original Report of Discovery: http://cfa-www.harvard.edu/iauc/08200/08284.html
McNeil's Log of Initial Sighting: http://spacsun.rice.edu/~has/Articles.html#McNeils%20Nebula
Chandra X-ray Observatory: http://chandra.harvard.edu/
Lowell Observatory: http://www.lowell.edu/
Theories of Planetary Formation: http://www.droxley.freeserve.co.uk/node8_ct.html
Further Studies of V1647 Ori: http://adsabs.harvard.edu/cgi-bin/nph-bib_query?2004astro.ph..8432K
McNeil's Astrophotography: http://wkaa.net/gallery/mcneil