Fraser Cain, Author at Universe Today

November 13, 2007December 26, 2015 by Fraser Cain

Earth Rise, Seen by Kaguya

The team that developed and launched the Japanese Kaguya mission to the Moon earned their entire salary on this photo right here – a high-definition image of the Earth, rising over the horizon of the Moon. It’s like the Apollo Earth-rise image… just in high-def.

Just to let you know, I actually cropped the image a bit to fit Universe Today a little better. If you’d like to get at the original 1920×1080 pixel image, click here. I made this baby my desktop. And so can you. Once you’re looking at the full-sized image in your browser, right click on it. There’s should be an option that lets you set it as your desktop.

Although people have romanticized about what astronauts would see standing on the surface of the Moon, it’s actually not possible. Since the Moon is tidally locked to the Earth, it shows the same face to us at all times. If you were standing on the surface of the Moon, the Earth is always in the same position in the sky at all times. So, you could never actually see the Earth rise above the horizon.

To capture a sequence like this, you’ve got to be in a spacecraft, orbiting the Moon, and looking towards the Earth. Then, as the spacecraft comes into the right position, the Earth will appear to rise above the horizon. So, it’s sort of a trick. But still… what a picture.

And what a way to put everything here on Earth back into perspective. As Carl Sagan said when talking about the pale blue dot of an Earth captured by NASA’s Voyage 1. But instead of “dot”, substitute, “cool high-definition image of the Earth”.

“Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.”

Thanks Carl. And thanks Kaguya, consider this mission a success. But still send the science, that’ll be helpful too.

Original Source: JAXA News Release

November 13, 2007December 26, 2015 by Fraser Cain

Comet Holmes is Bigger than the Sun

All right, that title is a little misleading. In fact, when I first read the original press release, my skepticism alarms went off. But it’s true, the amazing Comet Holmes now has a halo that’s larger than the Sun. Not bad for a comet that, until three weeks ago, was just a tiny dim dirty snowball orbiting near Jupiter.

Comet Holmes made its spectacular outburst on October 24, 2007. Formally dim enough to only be visible in the most powerful telescopes, it quickly brightened up to be seen with the unaided eye – even in light-polluted cities (like my very own Vancouver).

Astronomers from the University of Hawaii’s Institute for Astronomy recently measured the halo surrounding Comet Holmes to be 1.4 million kilometres (0.9 million miles). And as I mentioned in the opening paragraph, that makes it larger than the Sun. Of course, it’s just a thin halo of gas and dust particles, but still, that’s pretty impressive.

Just to get a sense of the change, Holmes has brightened by a factor of 500,000x. All this gas and dust is pouring out of a tiny nucleus only 3.6 km (2.2 miles) in diameter.

In the image captured by the Institute for Astronomy, you can make out the brighter nucleus, near the centre of the halo. And then there’s a hazy tail pointing towards the lower right of the image.

Over the next few months, astronomers predict the cometary halo will expand even larger; although, it will be fading away as the dust disperses over a larger volume.

Holmes performed a similar outburst back in 1892, and it brightened again just a couple of months later. Astronomers are hoping it’ll make another double outburst, just like it did before.

Original Source: IfA News Release

November 9, 2007December 26, 2015 by Fraser Cain

Podcast: When White Dwarfs Collide

There’s a certain kind of supernova that’s totally dependable. Let a white dwarf accumulate 1.4 times the mass of the Sun, and it’ll detonate in an explosion visible clear across the Universe. When astronomers saw supernova 2006gz, that’s what they thought they were dealing with, but hold on, the explosion was much more powerful than you would expect from just a single white dwarf. Maybe two came together in a colossal explosion.

Malcolm Hicken is a graduate student at the Harvard University Department of Physics, and he’s the lead author of the team that made the explosive discovery, published in the November 1st issue of The Astrophysical Journal Letters.

Click here to download the audio file.

November 9, 2007December 26, 2015 by Fraser Cain

Spitzer Sees a Baby Star Blowing Bubbles

A new image released from NASA’s Spitzer Space Telescope shows a baby star blowing bubbles, just like, I guess, a kid with bubblegum. But let’s see your kid hurl out material hundreds of kilometres a second across light-years of space. Those are some big bubbles.

The infant star is known as HH 46/47, and it’s located about 1,140 light-years from Earth. The star itself is that bright white spot at the middle of the image.

Surrounding the star are two bubbles of material extending out in opposite directions. These bubbles are formed when powerful jets of gas collide with the cloud of gas and dust surrounding the star. The red specks at each end signify hot sulfur and iron gas, where the jets are colliding head on into the gas and dust material.

Astronomers think that young stars accumulate material by gravitationally pulling in gas and dust. This process ends when the star gets large enough to create these jets. Any further material is just blown away into space.

Producing this image was a bit of a technical achievement. The researchers at NASA’s JPL developed an advanced image-processing technique for Spitzer data called Hi-Res deconvolution. The process reduces blurring, and makes the image sharper and clearer. With this technique, astronomers were able to make out the details of HH 46/47, and its surrounding bubbles.

Original Source: NASA/JPL News Release

November 9, 2007December 26, 2015 by Fraser Cain

Black Holes Linked to Cosmic Rays

You know that big list of unsolved mysteries in astronomy? Well, you can remove, “what causes the highest energy cosmic rays?” Thanks to new research using the Pierre Auger Cosmic Ray Observatory in South America, the answer appears to be: supermassive black holes.

High energy cosmic rays are actually particles – protons mostly – accelerated to tremendous velocities. When they crash into the Earth’s atmosphere, they explode in a spray of energy and sub-particles that can be detected here on the surface. Fortunately our atmosphere protects us from damage, but out in space, they’re a real threat.

Just a single particle can have the same energy as fast moving tennis ball.

Astronomers have been wondering for years how particles can get boosted to such high energy levels. A massive team of 370 researchers from 17 countries have been working on the answer using the newly developed Pierre Auger Cosmic Ray Observatory, nestled in the mountains of South America.

The observatory is actually an array of detectors spread out over a 3,000 km² area. As the cosmic rays collide with the atmosphere, the resulting spray of particles are caught by the detectors, which house large tanks of water. The detectors are so sensitive, they can detect a different in timing, which allow astronomers to triangulate the direction the cosmic ray came from. The particles are flung with such energy that they point back to their galaxies, like bullets coming from a gun.

Before the Pierre Auger observatory, cosmic ray detections were rare. Astronomers just didn’t have enough data to know where they were coming from. But over the last 3 years, the observatory has recorded a million cosmic rays, including 80 of the highest energy.

Astronomers now know that cosmic rays don’t come from all regions of the sky, but they’re shot out from actively feeding supermassive black holes.

The exact process that creates the cosmic rays isn’t fully understood, but astronomers think that the environment around an active supermassive black hole is ferocious, to say the least. Powerful magnetic fields are generated, which can act like natural particle accelerators, pushing protons to energy levels much higher than anything physicists could recreate with our technology.

Original Source: University of Chicago News Release

November 9, 2007December 26, 2015 by Fraser Cain

Rosetta Is Returning to Earth for Another Flyby

Mark your calendars for November 13th, 2007. That’s the day ESA’s Rosetta spacecraft will be making a close encounter with Earth on its way to Comet 67/P Churyumov-Gerasimenko. What’s going on? The comet’s out there guys, why is Rosetta back home? Well, it’s all about speed.

Launching spacecraft is an energy intensive business. You can only get a spacecraft going so fast when it launches directly from Earth. But using a technique called gravity assist, spacecraft can use the gravity of a planet – such as the Earth – to get a speed boost. Most of the robotic explorers do it.

In order for Rosetta to make its encounter with Comet 67/P Churyumov-Gerasimenko in 2014, it needs to be going much faster. It already got a gravity assist from Earth back in March 4, 2005, and another with Mars on February 25, 2007. Now its time for a third on November 13. We won’t be done with Rosetta yet, either. The spacecraft is due to make a 4th and final flyby on November 13, 2009.

Before it returns for the 4th flyby, Rosetta will swing out across the asteroid belt and observe asteroid Lutetia, testing out its scientific equipment.

Finally, in 2014, Rosetta will reach Comet 67/P Churyumov-Gerasimenko and begin some serious investigations; even landing a probe down on its surface.

Original Source: ESA News Release

November 9, 2007December 26, 2015 by Fraser Cain

Station Astronauts Wrap Up Leftover Tasks

Although Discovery returned safely to Earth, there were still a few unfinished tasks. The astronauts on board the International Space Station picked up the torch, and wrapped them up in a 6.5 hour spacewalk on Friday. This helps prepare the station for the upcoming launch of Atlantis, to deliver the European Columbus module.

Discovery landed on Friday at the Kennedy Space Center in Florida, completing 15 days in space. In addition to bringing and installing the new Harmony module, the astronauts redeployed a solar array to a new location. And that’s where the problems happened. While they were unfolding the array, a guide wire was caught, and tore open a fold between solar panels.

The astronauts were were able to build “cufflinks” that reconnected the panels, but this additional spacewalk meant that other tasks couldn’t be performed.

The goal of Friday’s spacewalk was to wrap them up. Commander Peggy Whitson and cosmonaut Yuri Malenchenko went outside the station today to disconnect various electrical cables and stowing them away. Some route power to visiting shuttles the others connect the shuttle’s docking port to the Destiny laboratory.

On Monday, flight engineer Dan Tani will use the station’s robotic arm to move the shuttle’s docking port from its current location on Destiny over to the newly attached Harmony module.

And then on Wednesday, another spacewalk will move the Harmony node to its permanent location on the Destiny module.

Two additional spacewalks are planned to hook up power, cooling and data connections to the Harmony module.

This crew is going to be busy.

Original Source: NASA Station News

November 7, 2007December 26, 2015 by Fraser Cain

“Student Questions” for Astronomy Cast

If you’re a student or teacher, and you’re working through astronomy right now, we’d like to help you out. Pamela and I will be running a special edition of Astronomy Cast for high school students.
We’ll help you gather up all the astronomy questions from your class, and then we’ll do a special episode just for you, answering everything.

If you’re interested in participating, check out Pamela’s blog, where she explains things in more detail.

We’ll be announcing this in the podcast as well, but I just wanted to let you know here. A big thanks to NASAâ€™s Gamma-ray Large Area Space Telescope Education and Public Outreach program for sponsoring this.

November 7, 2007December 26, 2015 by Fraser Cain

Is China Building a Space Station?

There are mixed reports coming out of China on their plans to loft a space station by 2020. A Chinese aerospace engineer, Long Lehao, mentioned to journalists that the China National Space Administration was planning to build a “small-scale 20 tonne space workshop”. But then space officials at the agency denied the report. So what’s going on?

The Chinese official new agency Xinhua reported that Li Guoping, a spokesman for the agency said, “China at present has not decided on developing a space station.” That sounds like the possibility is still open, in my opinion.

China has mentioned in the past that they’d like to launch a space station of their own, some time in the next 10 to 15 years. But they never pinned down a specific date, like the 2020 goal announced by Long Lehao. If the agency does have a firm date, Lehao would know. He’s a leading designer for the Long March 3A, the rocket that carried China’s Chang’e-1 lunar satellite into space.

And speaking of Chang’e-1, this contradicting news arrives just as the spacecraft has entered lunar orbit. After a two-week journey to the Moon, the spacecraft performed an orbiting maneuver so perfectly that the agency thinks they’ve saved a bunch of fuel. This fuel should allow the spacecraft to orbit the Moon for longer, delaying the inevitable date when it crashes down.

The first photos from Chang’e-1 should arrive later this month. And by early next year, the probe will have measured the entire surface of the Moon at least once.

And just in case you’re hoping the spacecraft will be able to image the Apollo astronaut footprints, sorry, it doesn’t have the resolution. But I’ll bet it’ll be able to see the landers.

Original Source: Xinhua Article

November 7, 2007December 26, 2015 by Fraser Cain

Discovery Lands Safely in Florida

NASA’s space shuttle Discovery touched down in Florida today, landing at Kennedy Space Center, and wrapping up a successful assembly mission to the International Space Station. The shuttle’s wheels touched pavement at 1:01 p.m. EST, with Commander Pam Melroy and Pilot George Zamka at the controls.

During their 15 days in space, the crew of STS-120 covered more than 10 million km (6.2 million miles). They attached the newly delivered Harmony Node 2 module, and relocated P6 truss. During the construction, one of the station’s solar arrays was torn, and so the astronauts completed an extra spacewalk to repair the damage.

In addition to the crew members who flew to the station, Discovery was carrying a special guest back to Earth: astronaut Clay Anderson. He spent the last 5 months living and working on board the station, and required a special reclining chair during re-entry to get used to the strength of Earth’s gravity after so much time being weightless.

Despite the resourceful repairs to the station’s power generating solar array, NASA managers are concerned that construction on the station may lag. The problems during Discovery’s mission has delayed other work on the station, and now construction is nearly a work behind schedule. The other shuttle missions are crammed together so tightly that there’s hardly any slack time. An upcoming mission to launch the European Columbus module may be in jeopardy.

Another problem is the metal fragments discovered in a wheel that rotates the station’s solar arrays. Without them rotating to always face the Sun, the station won’t be able to generate enough power to accommodate a Japanese laboratory due to arrive in April, 2008.

The next mission – STS-122 – will bring the space shuttle Atlantis back to the International Space Station. It’ll be carrying the European Columbus laboratory. It’s scheduled to launch on December 6th, but could get pushed back.

Original Source: NASA’s Shuttle Blog