Detecting cosmic ghosts in the night sky

When Yale University astronomer Kevin Schawinski and Oxford University associates won public support for enrolling galaxies, they never envisioned the strange object Hanny van Arkel discovered on the image of the night sky.

The young Dutch teacher, who is also a volunteer at the Galaxy Zoo project, allows the public to participate in online astronomy research programs, discovering a unique mysterious object that some observers call it 'cosmic specter'.

Van Arkel happened to see a picture of a strange gas-shaped object with a hole in the center while using the Galazy Zoo website to classify photos of the galaxy.

When she published the photo, it quickly got the name 'Hanny's Voorwerp' (Dutch for 'object') on the Galaxy Zoo forum. Web site astronomers began to learn and quickly realized that van Arkel might have discovered a new set of astronomical objects.

Schawinski, a member and co-founder of the Galaxy Zoo team - said: 'At first we didn't know what it was. It may be our solar system or it may be at the edge of the universe. '

Scientists use telescopes all over the world together with satellites in the universe are required to observe mysterious objects Vootwerp. "What we see is really a mystery," Schawinski said . Voorwerp doesn't have any stars'. Moreover, it is entirely made up of hot gas - about 10,000 degrees Celsius. Astronomers think it must rely on something very powerful to be able to glow. They will soon use the Hubble Space Telescope to look more closely.

Because the Voorwerp's light source data has not yet been obtained, the team has been looking for a source of light around Voorwerp, then they have turned to nearby galaxy IC 2497. "We think that in the recent past, galaxy IC 2497 has a very bright quasar," Schawinski explains . Due to the large gap between the galaxy and Voorwerp, the light from that past still illuminates the nearby Voorwerp, although quasars have been extinguished since about 100,000 years ago, while the galaxy's black hole has also gone silent. ' .

According to Chris Lintott, co-organizer of Galaxy Zoo at Oxford University (UK), 'From the perspective of Voorwerp objects, galaxy IC 2497 is still as bright as before the black hole faded away, it was the light remnant. frozen in time for us to observe. It's like checking the scene of the case where we know the killer is lurking somewhere in the dark even though we can't see him. ' It has been observed that the light of the remnants spreading far from supernovae has exploded for decades or centuries ago.

Photo of Voorwerp by Hanny and IC 2497. (Photo: Dan Smith, Peter Herbert, Matt Jarvis & the ING)

Quasars are unusual bright objects, which are powered by massive black holes. Most quasars are far away. C. Megan Urry - Israeli professor of physics and astronomy Munson, head of Physics at Yale, said: 'The strange' Hanny's Voorwerp 'object seems to be the closest example of a luminous quasar. The IC 2497 galaxy is very close so if the quasar is still glowing to this day, you can completely observe it with a small telescope on a beautiful night. The closest bright quasar called 3C 273 is 1.7 billion light years away. ' Megan Urry did not participate in this study.

Professor Bill Keel of the University of Alabama and a member of the Galaxy Zoo team commented: 'This finding really shows that public science has grown in the internet world. Hanny's attention alerted us not only to an unusual object but also to a door to the past of the universe that has eluded us for a long time. Understanding the ongoing process is certainly an interesting challenge, including many celestial physics techniques, tools around the world and more. This is also the most rewarding astronomy industry I have worked with for many years. '

The Galaxy Zoo project was proposed and implemented by Schawinski and his partner Chris Lintott. While conducting his doctoral dissertation, Schwinski classified and arranged more than 50,000 galaxies. Knowing that human eyes are more sensitive than computers to strange images, he thinks it would be great if astronomers were interested in 'scanning' images. .

Schawinski said: 'When we launched Galaxy Zoo - originally an internet portal, we were really overwhelmed by the passion of the public and volunteers'. Last year over 150,000 amateur astronomers from around the world dedicate their time and provide over 50 million classified materials including 1 million online photos.

Hanny van Arkel said: 'It is amazing to think that strange objects exist in decades of archival material and amateur volunteers can help by detecting objects like this via the internet. . This is a great gift for the 25th birthday of the crime. We will have time to observe with the Hubble Space Telescope to continue to explore this discovery. '

In the next step of the Galaxy Zoo project, volunteers will search for more unusual astronomical objects. But the 'Hanny's Voorwerp' object is still a mystery. It is the central giant black hole located 16,000 light-years away that Galaxy Zoo astronomers have a headache to think about and what created it.