Universe Today

December 1, 2008December 24, 2015 by Nancy Atkinson

Made in Korea: Lunar Lander Unveiled

The "homemade" Korean Lunar Lander. Credit: Korean Times

[/caption]
Everybody wants to go to the moon! Scientists from Korea recently unveiled a spacecraft developed completely in-house that could potentially be used for robotic exploration of the Moon. The mini-sized lander, shown above is about 40 centimeters tall (15.5 inches) and weighs 25 kilograms (55lbs). Scientists say it carry an additional 20 kilograms in payloads to the surface. Every part of the rocket engine was “homemade,” said Kwon Se-jin, a professor of aerospace engineering at the Korea Advanced Institute of Science and Technology (KAIST). The lander, the result of a six year long effort, represents an advancement in technology, and an important step for Korea’s nascent space program.

The rocket’s propulsion includes a state-of-the-art propulsion and the engine’s design allows it to be powered by environmentally friendly fuel. Also, the Korean team was proud of the low costs associated with their new lander.

According to Kwon, lunar modules between the 100 and 200 kilogram range, developed by NASA (National Aeronautics and Space Administration) under the International Lunar Network (ILN) project costs around $100 million. The rocket engine created by his team could cut development costs to about half that, Kwon claimed.

“We have approached NASA over the possibilities of using our engine,” Kwon said, adding that his team is collaborating with other local scientists with the goal of landing a spacecraft on the moon by 2013.

“Lunar-landers are critical in developing lunar spacecraft, but advanced nations have been careful to protect their core technologies, so I think this is a big deal for us,” he said.

South Korea has been pushing an aggressive space program over the past decade, and objectives include having a man on the moon by 2020.

Korea’s current plans are to launch an Earth-orbiting satellite in early 2009 from a newly built spaceport. If successfully, Korea would become the ninth country to launch a satellite from its own soil.

But the Koreans also want to become part of an international space research project, the ILN, a project aiming to gradually place six to eight fixed or mobile science stations on the lunar surface. The stations will form a robotic network to replace the hardware left by the Apollo program to continue studies of the moon’s surface and interior.

Source: Korea Times

December 1, 2008December 24, 2015 by Ian O'Neill

Old Space Observatory Spare Parts to Search for Dirty Bombs

The Compton Gamma Ray Observatory shortly after deployment by shuttle Atlantis (STS-37) on April 5th, 1991 (NASA)

[/caption]From 1991 to 2000, the Compton Gamma Ray Observatory dominated the search for the largest explosions ever observed in the cosmos: gamma-ray bursts (or GRBs). Unfortunately after nearly a decade of highly successful observations, June 4th 2000, NASA made the unpopular decision to de-orbit the observatory in response to a mechanical failure on the spacecraft (despite protests by some scientists, pointing out that the observatory could have continued operations).

To one scientist, Jim Ryan, the demise of the project he had tirelessly worked on since 1984 was a hard pill to swallow. However, in a surprise turn of events, the US Department of Energy tracked down Ryan and asked whether his research could be applied a little closer to home. In a flash of inspiration, the scientist realised spare parts left over from the Compton Gamma Ray Observatory could be used to pinpoint emissions from a potential “dirty bomb”, possibly providing security services with an early warning capability against a radioactive terrorist attack…

Although a dirty bomb has never been detonated and remain a speculative means by terrorists to cause maximum disruption to a populated area, the Department of Energy considers the threat to be very real. This is probably because a small amount of radioactive material could be used in the construction of a relatively cheap conventional bomb and plans by groups to use such weaponry have been uncovered in the past. The key power of a dirty bomb (otherwise known as a “radiological dispersal device”) isn’t the immediate health risk to a local population (apart from the obvious damage that could be caused by the conventional explosives used in the device), it is the lasting fear, panic and economic damage such a terror attack could cause. The residual radiation left over from a dirty bomb is of course a concern, but studies show that it is the psychological damage of such an attack that would have the greater effect.

So, the Department of Energy gave Dr Ryan a call to ask whether his work at the University of New Hampshire’s Space Science Center could be used to seek out radioactive devices. At the time, he was working on an instrument to be sent within the orbit of Mercury to detect low energy neutrons being emitted from the Sun. It just so happened that the neutron energy range matched that of the emission from plutonium.

“You don’t have to be an astrophysicist to see the connection,” Ryan commented on the government interest in using his techniques to search for nuclear devices on Earth.

However, during a visit to a National Guard exercise on Cape Cod, Jim Ryan was inspired by another space mission. The exercise carried out last year was to test security agent’s ability to track down dirty bombs (not nuclear weapons containing plutonium). Dirty bombs emit a different type of radiation (not the low energy neutrons emitted from a plutonium device), and Ryan realised that parts from his old and beloved Compton Gamma Ray Observatory may be resurrected to help serve national security tasks. Rather than manually scanning suspect radioactive devices with a hand-held Geiger counter, the gamma ray radiation can be detected at a safe distance and pinpointed. The problem with Geiger counters is that although they detect gamma radiation, you have to be standing right next to the radioactive source to know where it is. Using Compton Gamma Ray Observatory techniques can make the search safer and a lot more accurate.

“It lives on and does something that is useful to society as well as pure academic science,” Ryan said during a presentation to a Homeland Security conference in May. “[It is] poetic justice,” that the techniques by the spacecraft will be re-used by the modern fight against international terrorism.

Source: Boston.com

December 1, 2008December 24, 2015 by Nancy Atkinson

Wood Plank Found on Mars?

Panoramic image with "plank"-like rock. Credit: NASA/JPL/Cornell

Over the long holiday weekend, Universe Today was flooded with emails from readers who asked us to comment on an image taken by the Opportunity rover that appears to show a plank of wood laying on the surface of Mars. The image, above, (here’s the full resolution image) was taken in May of 2004, about four and a half years ago, in the early part of the Mars Exploration Rover mission. Since the image appears to have caused a bit of excitement across the internet recently, I decided to contact Dr. Jim Bell from Cornell University, who is also the lead scientist for the Panoramic cameras on the rovers. Bell was surprised to hear from me about the image, but happy to offer some insight. “My first reaction,” he said, “is that it’s delightful that there is such public interest in images from Mars.” Bell agreed that, indeed, it does look like a wooden plank. But does that mean it is a piece of wood on Mars? Sadly, no, says Bell.

“What you’re seeing is a piece of flat, platy, layered sulfur-rich outcrop rock like we’ve seen almost everywhere the Opportunity rover has been in Meridiani Planum,” said Bell. “Sometimes, like in this case, those flat, platy rocks have been tilted or dislodged, this one probably from the forces associated with the huge impact crater that formed nearby.”

See this image of several rocks in the area that have been tilted:

More tilted rocks. Credit: NASA/JPL/Cornell

“And this one’s being viewed edge-on,” Bell said, of the rock in question. “That edge-on view, combined with the layered nature of these rocks in general gives the surface a sort of grainy texture. So, indeed, it looks like a wooden plank on Mars.”

So, could it maybe be wood? “No, sadly,” said Bell. “I say ‘sadly’ because personally I think it would be incredible and spectacular to find a wooden plank on Mars! However, in this case, it’s just a trick of the lighting and the viewing angle.”

This image, as other Mars images that have created hubbub and speculation, is another example of our human tendency to see familiar shapes in random patterns. (Phil Plait talks about this pareidolia here.)

In fact, I spent most of the morning scanning through MER images from May 15-29, 2004 to see if I could find more images of this “wooden plank.” There’s plenty, as all of the MER images from all five cameras for both rovers are freely available on the rover website. I believe I found an image of the same rock, taken from the “backside” or opposite view: (see below)

Opportunity rover image from Sol 111. Credit: NASA/JPL

Here, it appears to be a rock, a tilted rock, but it doesn’t stand out because from this view, the lighting doesn’t make the rock appear as dark as the original view. Again, I’m not sure this is the same rock, but there are several images of tilted rocks in this region, and if this isn’t the same one, it’s one very much like it.

Here’s another image of rocks that have a similar “grainy” look to them:

Rocks with grainy surface. Credit: NASA/JPL/Cornell

For those of you who remain convinced that NASA is covering up some sort of “major” finding here, just remember a few things:

1. This image was released back in May of 2004, just a couple of days after it was taken by Opportunity. MER Principal Investigator Steve Squyres made the decision before the mission started to release all the images taken by the rovers and make them freely available to anyone. If NASA was hiding something, they wouldn’t have posted this image, as well as all the other images of the area that are available. Please, go look at them all if you have any doubt.

2. The best planetary geologists on Earth have looked at this image, and have all concluded this is just a rock. It’s an interesting rock, but a rock nonetheless. Think again if you believe some internet sleuths out there have a better understanding of this object than highly trained and experienced planetary scientists.

3. If this object really was a piece of wood, NASA and all the scientists on the MER mission would probably be shouting from the rooftops. As Jim Bell said, it would be incredible and spectacular, and don’t think for a minute these scientists wouldn’t be jumping for joy if they found something as amazing as log on Mars.

And in case you’re wondering about the other interesting feature in the image, the shiny object in the background is Opportunity’s heat shield.

December 1, 2008December 24, 2015 by Nancy Atkinson

Shuttle Landing: Beautiful; Progress Docking: Last-Minute Excitement

[/caption]
Sunday was a busy day for human spaceflight, as space shuttle Endeavour landed safely at Edwards Air Force Base in California, and a Progress re-supply ship docked at the International Space Station. While the shuttle landing went off without a hitch, problems developed with an automated docking system for the Progress ship, forcing a last-minute switch to a manual docking, performed by Russian cosmonaut Yuri Lonchakov. A series of problems including the loss of frequency information and unexpected toggling of the automatic system’s tracking displays occurred, Russian news agencies reported. But Lonchakov, who was already at the manual controls as a precaution, took over from the automated system when the Progress was about 30 meters (98 feet) from the station and guided it flawlessly to the docking port within a few minutes.

ISS Commander Mike Fincke and Yuri Lonchakov give thumbs up after a successful manual docking of the Progress vehicle. Credit: NASA TV

The decision to land in California was made early Sunday morning, as thunderstorms and strong winds prevented Endeavour from attempting either of the two landing opportunities at Kennedy Space Center in Florida, the primary landing site.

The clear blue skies in southern California made for a picturesque landing, with a great view of the shuttle as it quickly dropped through the sky.

Endeavour touched down at 3:25 p.m Central time.

Endeavour arrived at the station Nov. 16, delivering equipment that will help allow the station to double its crew size to six. The new gear includes a water recovery system, which will allow urine and other condensate to be purified and converted into water for the crew’s use. Endeavour returned with samples of the processed water for experts in Houston to analyze before it is approved for use by the crew.

Endeavour’s astronauts also repaired and serviced crucial rotating joints for the station’s giant solar arrays. During four spacewalks, the astronauts lubricated and cleaned the joints that allow the arrays to automatically track the sun.

In addition, Expedition 18 Flight Engineer Sandy Magnus replaced Greg Chamitoff as part of the ISS crew. Chamitoff returned to Earth aboard Endeavour.

STS-126 is the 124th shuttle mission and 27th shuttle flight to visit the space station.

Progress vehicle as it approached the ISS. Credit: NASA TV

The Progress vehicle, which blasted off from the Baikonur Cosmodrome in Kazakhstan on November 26, was carrying water, scientific equipment as well as personal items and holiday gifts for the ISS crew.

Sources: NASA, AFP

December 1, 2008December 24, 2015 by Tammy Plotner

Moon, Venus and Jupiter Dazzle on December 1

Venus, Jupiter and Moon - Shevill Mathers

[/caption]

Are you ready for some spectacular sky scenery tonight? Then keep your fingers crossed for clear weather as the slender crescent Moon, Venus and Jupiter provide one of the finest sky shows we’ve seen all year – a conjunction in the west to dazzle the eye and boggle the brain! But just exactly why does seeing bright planets draw together command our attention? Step inside and let’s find out…

“Your eye is like a digital camera,” explains Dr. Stuart Hiroyasu, O.D., of Bishop, California. “There’s a lens in front to focus the light, and a photo-array behind the lens to capture the image. The photo-array in your eye is called the retina. It’s made of rods and cones, the fleshy organic equivalent of electronic pixels.” Near the center of the retina lies the fovea, a patch of tissue 1.5 millimeters wide where cones are extra-densely packed. “Whatever you see with the fovea, you see in high-definition,” he says. The fovea is critical to reading, driving, watching television. The fovea has the brain’s attention. The field of view of the fovea is only about five degrees wide.” Tonight, Venus, Jupiter and the crescent Moon will all fit together inside that narrow angle, signaling to the brain, “this is worth watching!”

When it comes to our eyes, almost every photoreceptor has one ganglion cell receiving data in the fovea. That means there’s almost no data loss and the absence of blood vessels in the area means almost no loss of light either. There is direct passage to our receptors – an amazing 50% of the visual cortex in the brain! Since the fovea doesn’t have rods, it isn’t sensitive to dim lights. That’s another reason why the conjunctions are more attractive than the surrounding starfields. Astronomers know a lot about the fovea for a good reason: it’s is why we learn to use averted vision. We avoid the fovea when observing very dim objects in the eyepiece.

Let’s pretend we’re a photoreceptor. If a light were to strike us, we’d be “on” – recording away. If we were a ganglion cell, the light really wouldn’t do much of anything. However, the biological recorder would have responded to a pinpoint of light, a ring of light, or a light with a dark edge to it. Why? Light in general just simply doesn’t excite the ganglion, but it does wake up the neighbor cells. A small spot of light makes the ganglion go crazy, but the neighbors don’t pay much attention. However, a ring of light makes the neighbors go nuts and the ganglion turns off. It’s all a very complicated response to a simple scene, but still fun to understand why we are compelled to look!

Many of us have been watching the spectacle draw closer over the last several days. How many of you have seen the Venus and Jupiter pair appear one over the top of each other – looking almost like a distant tower with bright lights? What we’ve been observing is Kepler’s Laws of Planetary Motion in action – and it’s a great way to familiarize yourself with celestial mechanics. What’s happening tonight is called a conjunction. This is a term used in positional astronomy which means two (or more) celestial bodies appear near one another in the sky. Sometimes the event is also called an appulse.

No matter what you call it, what you’ll see tonight is a worldwide happening and will look hauntingly like a “happy face” painted on the early evening sky. Don’t miss it!

Our deepest appreciation goes to Shevill Mathers for his dedication in getting this shot to share with us, and all the rest of the great astrophotographers at Northern Galactic and Southern Galactic who have also gave it their best shot! There can be only one…

November 29, 2008December 24, 2015 by Fraser Cain

Axis Tilt of Neptune

Neptune from Voyager 2. Image credit: NASA/JPL

[/caption]
For all the things different about Neptune from Earth, here’s something that’s remarkably similar. The tilt of Neptune’s axis is 28.32 degrees. Compare that to the Earth’s tilt of 23.5 degrees.

With such a similar axial tilt, Neptune has very similar seasonal variations to Earth. For half of its orbit around the Sun, Neptune’s northern pole is tilted towards the Earth, and then for the other half of its orbit, the southern pole faces the Sun.

One of the biggest effects of the seasonal variation on Neptune is the current “hotspot” at Neptune’s southern pole. While most of Neptune has an average temperature of around -200 Celsius, Neptune’s south pole is about 10 degrees warmer. This makes the south pole warm enough so that methane gas – frozen in the rest of Neptune’s atmosphere – can escape into space.

Once Neptune’s seasons reverse, the hotspot will shift back to Neptune’s north pole.

We have written many stories about Neptune for Universe Today. Here’s an article about how there could be oceans deep down within Neptune’s interior, and some movies of Neptune captured by Hubble.

If you’d like more information on Neptune, take a look at Hubblesite’s News Releases about Neptune, and here’s a link to NASA’s Solar System Exploration Guide to Neptune.

We have recorded an entire episode of Astronomy Cast just about Neptune. You can listen to it here, Episode 63: Neptune.

November 29, 2008April 26, 2016 by Nancy Atkinson

Pictures of Canadian Meteorite Fragments

University of Calgary graduate student Ellen Milley poses with a fragment of a meteorite in a small pond. AP Photo/The Canadian Press, Geoff Howe

[/caption]
On Nov. 27, planetary scientist Dr. Alan Hildebrand from the University of Calgary and graduate student Ellen Milley brought reporters to a site where they have found numerous meteorite fragments from the bolide that streaked across the sky in Western Canada on Nov. 20. The area where the meteroite fragments were found is called Buzzard Coulee, about 40 kilometers from the town of Lloydminster, on the Alberta-Saskatchewan border. There, around a frozen pond, numerous small rocks and pebbles could be seen that the scientists said were from the meteorite. No large chunks were spotted, however, reporters said.

Fragments of a meteorite were found in a small pond at Buzzard Coulee, Sask. on Friday. (Geoff Howe/CP)

The fireball that streaked across western Canadian skies was witnessed by thousands, and Hildebrand believes it was a 10-ton fragment from an asteroid. Videos from surveillance and police cameras showed the meteor exploding before it hit the ground. Reporters were told those observations, combined with the physical evidence, give scientists a treasure trove of data that could give them a better understanding of the solar system. The reports don’t offer any indications of the type of meteorite the fragments are, but from the images they appear to possibly be iron. We’ll add more images and information as they become available.

Sources: CBC.com,
, Washington Post, Phys.Org

November 28, 2008December 24, 2015 by Nancy Atkinson

Wilkins Ice Shelf in Danger

Wilkins Ice Shelf, Credits: A. Humbert, Münster University, Germany (based on ESA Envisat images)

[/caption]
Recent satellite images show new rifts have developed on the Wilkins Ice Shelf which could possibly lead to the opening of the ice bridge that has been preventing the shelf from disintegrating and breaking away from the Antarctic Peninsula. The ice bridge connects the Wilkins Ice Shelf to two islands, Charcot and Latady. As seen in the image above acquired Envisat on November 26, 2008, new rifts (denoted by different colored lines and dates of the events) have formed to the east of Latady Island and appear to be moving in a northerly direction. “These new rifts, which have joined previously existing rifts on the ice shelf (blue dotted line), threaten to break up the chunk of ice located beneath the 21 July date, which would cause the bridge to lose its stabilization and collapse,” said Dr. Angelika Humbert from the Institute of Geophysics at Münster University.

The Wilkins Ice Shelf, a broad plate of floating ice south of South America on the Antarctic Peninsula, had been stable for most of the last century before it began retreating in the 1990s. The peninsula has been experiencing extraordinary warming in the past 50 years of 2.5°C.

In the past 20 years, seven ice shelves along the Antarctic Peninsula have retreated or disintegrated, including the most spectacular break-up of the Larsen B Ice Shelf in 2002, which Envisat captured within days of its launch.

Map showing break-up events of Larsen-B and Wilkins ice shelves, as observed by Envisat, in Antarctica. Credits: ESA

In February 2008 an area of about 400 km² broke off from the Wilkins Ice Shelf, narrowing the ice bridge down to a 6 km strip. At the end of May 2008 an area of about 160 km² broke off, reducing the ice bridge to just 2.7 km. Between 30 May and 9 July 2008, the ice shelf experienced further disintegration and lost about 1,350 km².

If the ice shelf breaks away from the peninsula, it will not cause a rise in sea level since it is already floating. However, ice shelves on the Antarctic Peninsula are sandwiched by extraordinarily raising surface air temperatures and a warming ocean, making them important indicators for on-going climate change.

Source: ESA

November 28, 2008December 24, 2015 by Fraser Cain

Life on Neptune

Neptune, captured by Voyager 2. Image credit: NASA

[/caption]
We know there’s life on Earth, but could there be live on Neptune? And if there is life on Neptune, what kind of life is it?

Wherever we find liquid water on Earth, we find life. Whether that water is thousands of meters beneath the ground, inside nuclear reactors, or inside glaciers. As long as there’s water, there’s life. Of course, it’s just microbial life – but still, life.

To find life on Neptune, the planet would need to have a source of energy that bacterial life can exploit, as well as a standing source of liquid water. At its surface, the temperature of Neptune dips down to 55 Kelvin. That’s very cold, and there’s no way liquid water could exist.

But as you travel down into Neptune’s interior, temperatures and pressures increase. And there could very well be a point inside the planet where water remains as a liquid, and life could exist inside it. Of course, this region would be hundreds of kilometers below the surface, and would be impossible for us to study. So for now, it will have to remain a mystery.

Right now, scientists don’t know if there’s any life on Neptune, and the conditions on the planet seem very hostile for life. It’s unlikely we’ll ever find any there.

We wrote a detailed article on Universe Today about the possibility that there are oceans inside Neptune and other gas giant planets.

If you’d like more information on Neptune, take a look at Hubblesite’s News Releases about Neptune, and here’s a link to NASA’s Solar System Exploration Guide to Neptune.

We have recorded an entire episode of Astronomy Cast just about Neptune. You can listen to it here, Episode 63: Neptune.

November 28, 2008March 24, 2012 by Nancy Atkinson

Fragments of Canadian Fireball Found

Fragments of the big meteorite that lit up the Canadian skies across the provinces of Alberta and Saskatchewan last week have been found, according to a report in CBC online. University of Calgary scientists said they located several meteorite fragments late Thursday afternoon, and they were planning to take reporters to the site Friday. Planetary scientist Dr. Alan Hildebrand and graduate student Ellen Milley believe thousands of meteorite bits from the 10-ton bolide are strewn over a 20-square-kilometre area. The video above of the fireball was taken by a video camera in a police car in Edmonton, Alberta.
Continue reading “Fragments of Canadian Fireball Found”