NASA’s WISE Mission Captures Black Hole’s Wildly Flaring Jet
Astronomers using NASA’s Wide-field Infrared Survey Explorer (WISE) have captured rare data of a flaring black hole, revealing new details about these powerful objects and their blazing jets.
Scientists study jets to learn more about the extreme environments around black holes. Much has been learned about the material feeding black holes, called accretion disks, and the jets themselves, through studies using X-rays, gamma rays and radio waves. But key measurements of the brightest part of the jets, located at their bases, have been difficult despite decades of work. WISE is offering a new window into this missing link through its infrared observations.
“The planet is relatively small at around 60,000 km in diameter (still, it’s five times the size of Earth). But despite its diminutive stature, this crystal space rock has more mass than the solar system’s gas giant Jupiter.
Radio telescope data shows that it orbits its star at a distance of 600,000 km, making years on planet diamond just two hours long. Any closer and it would be ripped to shreds by the star’s gravitational tug.”
This map shows the locations of many spacecraft that have landed on the moon. Green triangles represent Apollo missions. Yellow are NASA Surveyor missions, and red are Russian Luna spacecraft. One of the Lunar Reconnaissance Orbiter’s missions is to search for potential landing sites for future manned missions to the moon.
Credit: National Space Science Data Center, NASA’s Goddard Space Flight Center
Apophis is a 46 million tonne asteroid that will pass within a hair’s breath of Earth in 2029. However, Apophis’s trajectory is likely to take it through a region of space near Earth known as a keyhole that will ensure the asteroid returns in 2036.
Nobody knows how close Apophis will come on that pass. But if there’s a chance of a collision, we’ll have only 7 years to work out how to avoid catastrophe.
Researchers at Tsinghua University in Beijing say their preference is to use a solar sail to place a small spacecraft into a retrograde orbit and on collision course with Apophis. The retrograde orbit will give it an impact velocity of 90km/s which, if they do this well enough in advance, should lead to a collision large enough to do the trick.
In 2002, the European Space Agency began a program called Don Quijote to find out how best to perform such a deflection.
Don Quijote involves sending two spacecraft to a near Earth asteroid; one to smash into it and the other to watch while in orbit above the impact crater. The goal is to change the asteroid’s semimajor axis by more than 100 metres and to measure the change with an accuracy greater than 1 per cent.
This aurora arched from horizon to horizon. During the current Shelios expedition to observe and learn about the northern lights, the sky last weekend did not disappoint. After sunset and some careful photographic planning, the above image was taken from the expedition’s Qaleraliq campsite in southern Greenland. Visible straight through the center of the aurora, found with a careful eye, is the Big Dipper and the surrounding constellation of the Big Bear (Ursa Major). The brightest orb on the far right is the Moon, while Jupiter can be seen even further to the right. The Shelios expedition is scheduled to last until the end of August and include live broadcasts of ongoing auroras. (via APOD: 2011 August 23 - Aurora Over Greenland)