So this is what I’ve been working on for the past two months. Finally finished it, will be giving it to my mom tomorrow night.
Monthly Archives: December 2011
Before penguins ruled Antarctica, dinosaurs roamed across what was then a forested continent, migrating over from Australia and other land masses that were connected to it at the time. Several Antarctic dinosaurs have already been found, including an armored ankylosaur and a handful of birdlike dinosaurs. But researchers working on James Ross Island off the Antarctic Peninsula have now reported the discovery of what may be the biggest dino yet: a fossil (inset) from the tailbone of a sauropod, a giant, four-legged dinosaur with a long neck and tail. As they write in Naturwissenschaften this week, the researchers believe this plant-eating beast lived during the Cretaceous period, which lasted until about 65 million years ago. The team can’t identify which of the 150 sauropod species the dinosaur belonged to, but it hopes to find some of his friends still buried in the frozen wasteland.
Sorry I haven’t been blogging lately, I have been working very hard on trying to complete a present for my mom. In January 2011 my dad passed away (I’m working on a true story of this event, but it is difficult to write) and I wanted to make something very special for my mom. What I’ve done is create an Angel puzzle box that contains a single heart ornament with my dad’s photo in it. It should be done in a day or two and I will post the photos. It is coming together much better than I would have thought!
Love to all, and to all a Merry Christmas.
Every starship captain knows the true prime directive: steer clear of black holes. Well it appears that one object didn’t get the memo. According to a new study, a small cloud of gas and dust is racing toward the black hole at the center of the Milky Way—and when it hits, be prepared for some astronomical fireworks.
The black hole, named Sagittarius A*, weighs 4 million times as much as our sun and is 27,000 light-years away. Every star in the Milky Way revolves around it. Our sun takes 230 million years to complete an orbit, but one known star is so close that it revolves around Sagittarius A* in just 16 years.
Now astronomers have spotted a new object near the black hole. Stefan Gillessen and Reinhard Genzel of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and their colleagues used the European Southern Observatory’s Very Large Telescope in Chile to observe the Milky Way’s center at infrared wavelengths, which penetrate the thick dust between it and us. The instrument picked up a small gas cloud that, over 9 years of observations, appeared to be getting closer and closer to Sagittarius A*. The astronomers detected the object at a wavelength of 3.76 microns but not at 2.16 microns. This indicates it is a cloud of gas and dust rather than a star, they say, because a star is so hot that it should be brighter at the shorter wavelength.
The cloud is about three times as massive as Earth, emits five times as much energy as the sun, and spans 250 times the distance from the Earth to the sun. Its temperature is about 550 kelvin—somewhat cooler than the surface of Venus. Sagittarius A*’s immense gravity is accelerating the cloud dramatically: in 2004, the cloud was hurtling toward the black hole at 1200 kilometers per second; by 2011, the speed had nearly doubled, reaching 2350 kilometers per second. At that velocity, an airplane could circle the Earth in 17 seconds.
The cloud will approach Sagittarius A* in the summer of 2013, when the center of the gas and dust will be 260 times as far from the black hole as Earth is from the sun. But as the cloud hits hot gas already orbiting the black hole, it will likely meet its end. “It became really exciting when we noticed in the 2011 data that the cloud is starting to be stretched like spaghetti,” Gillessen says. “So right in front of our eyes, we can see the black hole is destroying the cloud. The material will rain down into the black hole and release a tremendous amount of energy.” As pieces of the cloud fall into Sagittarius A* over the next decade, friction and gravity will heat them to temperatures of millions of degrees, producing x-rays , the team reports online today in Nature. Other astronomers have detected “echos” of x-rays near the galactic center—reflections of radiation that have lit up large clouds hundreds of light-years away and that likely arose when past clouds dove into the black hole and sparked outbursts of x-rays.
Astronomer Andrea Ghez of the University of California, Los Angeles, who has seen the same object in her data, wouldn’t bet her house on such drama unfolding, however. “A much more likely interpretation is that this is a star that has an infrared excess,” she says, noting that dust surrounding a star can absorb visible light and reemit it in at infrared wavelengths. If the object is merely a star, then it won’t fall into the black hole but will shoot past it as the star loops around Sagittarius A* every 140 years. Ghez says other stars with infrared excesses exist near the galactic center.
Who’s right? We’ll find out by 2013. If the object really is a gas cloud, the fireworks (at x-ray and infrared wavelengths) should reveal the extreme conditions that prevail around the galaxy’s biggest black hole — useful information not only for astronomers studying supermassive black holes in other galaxies but also for starship captains the next time they voyage to the Milky Way’s hub.