Stories tagged The Universe

Sep
29
2007

A terrifying burst of cosmic energy: JGordon not pictured.  (Image courtesy of Wikimedia Commons)
A terrifying burst of cosmic energy: JGordon not pictured. (Image courtesy of Wikimedia Commons)
Scientists have recently reported observing a massive, and as of yet unexplained, burst of radio energy from across the universe. At the time of the event, I was probably in the shower, or watching TV, and, in either case, too far from my radio telescope to see what was happening.

Researchers say that the burst was unlike anything seen before, coming from at least one and a half billion light years away, and giving off as much energy as a large power station running for two billion years. I guess I have to take the scientists' word for it, although that seems like an awful lot of energy for me to miss. The event lasted for only five milliseconds, though, so it seems possible that it could have slipped my notice.

"The burst may have been produced by an exotic event such as the collision of two neutron stars or be the last gasp of a black hole as it evaporates completely," says Professor Duncan Lorimer of the University of West Virginia. Based on my own knowledge of cosmic events, I'd say it's equally likely that the energy burst came from a galactic scale conflict between, say, Thanos and Adam Warlock, or the utter destruction of a planet, as observed in Star Wars IV: A New Hope. However, I can't yet say either way for sure.

Scientists believe it's possible, however peculiar it may seem, that similar events may be occurring several times a day. The difficulty in actually spotting one just comes from the sky being so big, a fact that I can confidently confirm.

Sep
25
2007

Explore the universe

Google Sky
Google Sky
Want to explore the universe? With views of 100 million stars and 200 million galaxies, Google Sky lets you be a virtual space traveler with just a few clicks of a mouse.

Download Google Earth

To get started on your own outer-space adventure, download the most recent version of Google Earth software. Select "Switch to Sky" under the "view" menu or click on the icon that I show with a red arrow.

You might need a guide

The Universe is a big place so you might get lost. For help, the column on the left offer lots of guided tours. Try the sightseeing link under places. The screen capture shows what I found by selecting "Supernovae and Exotic Stars" under the layers section. PCworld has created a file of Google Sky Placemarks. Download it and open it with Google Earth. In the left column, in the Places box, click the (+) next to "Spectacular Sights in Google Sky". These are like bookmarks (or stick pins) that take you to some fantastic places. One (A Dramatic Outburst - V838Mon) has a time line slider so you can see how the event changed over several years.

Have fun

Google sky incorporates high-resolution images from NASA's Hubble Space Telescope, the Space Telescope Science Institute, the Sloan Digital Sky Survey, and the Digital Sky Survey Consortium into a fun, interactive learning tool. I hope you can check it out (high speed internet required).

Sep
21
2007

The Moon: Photo courtesy NASA.
The Moon: Photo courtesy NASA.
The new documentary IN THE SHADOW OF THE MOON is both inspirational and awe-inspiring in its retelling of NASA’s Apollo program to place a man on the Moon by the end of the 1960s. The great thing about it is that it’s the Apollo astronauts themselves who tell the story.

Director David Singleton interviewed 10 of the remaining astronauts who had traveled to the Moon and back including Jim Lovell (Apollo 8 and 13), Gene Cernan (Apollo 10 and 17), Dave Scott (Apollo 15), Alan Bean (Apollo 12), Harrison Schmitt (Apollo 17), Charlie Duke (Apollo 16), and Mike Collins and Buzz Aldrin (Apollo 11). Neil Armstrong, the first man to walk on the Moon, is not interviewed, but the notoriously reclusive astronaut appears quite a bit in the film, and of course can be heard taking his famous first step on the Moon’s surface.

Besides the many technical triumphs, the film also touches on some of the setbacks NASA faced in its race to fulfill president Kennedy’s seemingly impossible lunar-landing dream, including exploding Saturn V rockets, the Apollo 1 fire that killed three astronauts, and Apollo 13’s doomed mission.

I’m a big fan of the whole Man on the Moon adventure, so a lot of the NASA film footage used in the film was already familiar to me, but some scenes (especially one when Apollo 11’s command module heads off toward the Moon) were a complete surprise, and just seeing it all on the big screen was a real treat.

Astronaut Alan Bean on the adventure of his life: Photo courtesy NASA.
Astronaut Alan Bean on the adventure of his life: Photo courtesy NASA.
The astronauts themselves – now in their seventies - come off much warmer and more human than I expected. Alan Bean, in particular, seemed like an exuberant child telling you all about the great amusement ride he got to go on.

So if you remember where you were when Neil Armstrong exclaimed “Houston, the Eagle has landed”, and even if you don’t - or even if you weren’t born yet – I recommend you see this really great film. You’ll relive, or experience for the first time, all the excitement of one of mankind’s boldest and greatest achievements.

Sep
19
2007

A dazzling fireball comes blazing in: Photo by Hiroyuki Iida of Toyama, Japan, courtesy NASA.
A dazzling fireball comes blazing in: Photo by Hiroyuki Iida of Toyama, Japan, courtesy NASA.
Hundreds of Peruvian villagers have reportedly fallen ill from what they say are noxious gases coming from an impact crater left by something from space that slammed into the region.

A fiery object was seen falling to Earth last weekend over Carancas, a small town located in the Andes near in the Bolivian border, about 800 miles south of Lima.

People who visited the reported impact site say gases emitting from a large crater found there have caused them to suffer nausea, vomiting, eye irritations, and severe headaches. Livestock in the area have also become sick.

But not everyone believes the located “impact crater” has anything to do with the fiery object seen in the sky. Dr. Caroline Smith, a British museum meteorite expert, says it may just be mistaken for a crater.

"Increasingly we think that people witnessed a fireball, which are not uncommon, went off to investigate and found a lake of sedimentary deposit, which may be full of smelly, methane rich organic matter," she said.

An engineer from the Peruvian Nuclear Energy Institute reported no radiation has been detected at the site, and a team of scientists is on its way to the crater to investigate and gather further evidence. In the meantime, local authorities have been asked to warn people to stay away from the site.

Video from the site shows what appears to be a large crater 100-foot-wide by 20-foot-deep (another source states the crater is half this size). Marco Limache, a local official, reported that "boiling water started coming out of the crater, and particles of rock and cinders were found nearby."

If it proves to be a meteor crater, then it’s possible that sulfur or other elements in the extraterrestrial rock that caused the impact could have reacted with the ground water to produce the noxious gases.

Whatever it was - a fireball or a meteorite or possible space junk returning to Earth – it’s made a lot of local people nervous, and worried that the water is no longer safe to drink.

"This is the water we use for the animals, and for us, for everyone, and it looks like it is contaminated,” said one local villager.

"We don't know what is going on at the moment, that is what we are worried about,” he added.

LINKS

BBC web site story
Cosmos magazine story

Sep
13
2007

The Orion crew exploration vehicle: This rendering represents a concept of the Orion crew exploration vehicle. NASA's Constellation Program is getting to work on new spacecraft that will return humans to the moon and blaze a trail to Mars and beyond.  Image courtesy:Lockheed Martin Corp.
The Orion crew exploration vehicle: This rendering represents a concept of the Orion crew exploration vehicle. NASA's Constellation Program is getting to work on new spacecraft that will return humans to the moon and blaze a trail to Mars and beyond. Image courtesy:Lockheed Martin Corp.
Here are some more random questions that were submitted to our featured Scientists on the Spot that had nothing to do with their area of expertise. A few were space related, so I gathered them up to answer together.

We had two similar space travel questions. ”How many days does it take to get to the moon?” and, ”How many years does it take to get to Mars?”

First, the moon, which is closer, and rotates around the Earth. That simple fact may make you a lot of money some day.

How long it takes to get to the moon depends on how fast you are traveling and whether or not people are on the ship.

The moon is 238,855 miles from Earth. If you were to travel at a rate of 60 miles an hour from the Earth to the moon it would take165 days to get there. Luckily, spaceships can travel a lot faster.

The first man-made spacecraft to reach the moon was the Soviet Union’s unmanned Luna 2. It reached the moon in 33½ hours, meaning it traveled at an average of 7,131 miles an hour.

Manned spacecraft take longer to reach the moon as you have to take into consideration g-forces, safety and probably resting by the crew. The first manned lunar landing, Apollo 11, was launched from Earth at 1:32pm on July 16, 1969, achieved orbit around the moon some nearly 76 hours later, and made landing on the moon at 8:17pm on July 20, 1969. Apollo 12, the second moon mission, took the longest to get to the moon – over 83 hours, while Apollo 16 was the fastest at just under 72 hours. So, I would say it takes around three days to get to the moon.

Apollo 17 was the last lunar landing, back in December of 1972. NASA has plans to return to the moon in 2019.

Like going to the moon, the time it takes to get to Mars is influenced by how fast you travel, but another crucial factor is that Mars’ distance from Earth changes as the two planets rotate around the Sun, so how long it takes depends on when you leave. Recent unmanned missions to Mars included Spirit (launched June 10, 2003 – arrived January 3, 2004), Pathfinder (December 4, 1996 – arrived July 4, 1997), Mars Odyssey (launched April 7, 2001 – arrived October 24, 2001) and the Mars Reconnaissance Orbiter (launched August 12, 2005 – arrived March 10, 2006), and they average just over 6 months.

Supernova Cassiopeia A: This image from the orbiting Chandra x-ray observatory shows Cassiopeia A, the youngest supernova remnant in the Milky Way. Image courtesy: NASA/CXC/MIT/UMass Amherst/M.D.Stage et al.
Supernova Cassiopeia A: This image from the orbiting Chandra x-ray observatory shows Cassiopeia A, the youngest supernova remnant in the Milky Way. Image courtesy: NASA/CXC/MIT/UMass Amherst/M.D.Stage et al.
It would be about the same about of time for a manned spaceflight, if launched during the time when the two planets are in opposition to one another. The length of time spent on Mars will be impacted by this as well – it will either be a 30-day stay (a total 600+ day mission) or a 450+ day stay (a total 900+ day mission). Again, the difference lies in when the planets are in opposition, which only occurs every 26 months.

The final space question is “What are super novas?”

Super novas are stars blowing up. (Sweet.) Basically, the blowing up star becomes much brighter (because it is blowing up) as the material that made up the star is blown away.

More on supernovas can be found here, here or here.

Aug
28
2007

Anybody see the eclipse last night? It looked something like this.

Looking ahead, Charles Deehr of the University of Alaska sends word of a great meteor shower coming on the night of August 31 / September 1. Unfortunately, by the time it hits, the eastern and Midwestern US will already be in daylight. This shower will only be visible on the West Coast, Hawaii and similar places. It's expected to start around 4:00 am PDT, plus or minus 20 minutes, so Californians need to get out there around 3:30 and look east.

He also tells us we may see some aurora activity around the equinox (September 22). The Sun is not particularly active this year, so it won't be a spectacular display -- though he expects next year to start getting better. Anyway, readers in Canada, Alaska, Scandinavia, and the very northern US (northern Minnesota, the UP, places like that) might get lucky and see some.

Aug
25
2007

A whole lotta nothing: Actual image of nothing.  Photo courtesy Bryan Kennedy.
A whole lotta nothing: Actual image of nothing. Photo courtesy Bryan Kennedy.
This post is about nothing. A whole lot of nothing as a matter of fact. Or would it be better phrased: a fact of no matter? I’m not sure which is correct in this case.

Anyway, University of Minnesota astronomy professor Lawrence Rudnick and his research team has discovered an area in space – check that – a HUGE area in space where there seems to be a tremendous amount of nothing. Empty space. No stars, no planets, no dust, no dark matter, no Big Bang residual microwave energy, no nothing. I mean, yes nothing. And plenty of it.

"This is 1,000 times the volume of what we sort of expected to see in terms of a typical void," said Prof. Rudnick.

There’s evidently so much of it, in fact, that if you were able to travel at the speed of light (186,000 miles per second – or about 5.8 trillion miles per year) – it would take you about a billion years to cross it. Talk about a snooze-fest. I’d be completely bored to tears after the first two or three years.

But it seems appropriate that Rudnick be the one to discover this vast emptiness, since he seems to specialize in nothing.

He’s been teaching at the University of Minnesota since 1979, and has offered first year seminars in “Nothing”, bringing in experts to instruct his students on how “nothingness” is used or applied in various fields.

"It has a little bit of philosophy. I bring in people in different fields to talk about nothing in their fields. I've had artists come and talk about minimalist art, interior designers to talk about designing empty spaces,” Rudnick said. “I've had a blind person come and talk about seeing nothing and what does that mean."

Rudnick’s discovery came out of studying radio picture data of the universe taken from the National Radio Astronomy Observatory.
The area studied is located in the constellation Eridanus near the foot of Orion, and showed a distinct drop in temperature and lack of matter, up to 45% less matter.

Even though it’s really nothing, Rudnick remains modestly philosophical about it.

"It's not going to be tomorrow's pacemaker or anything like that," he said. "It is, however, part of the story of how we got here."
Rudnick’s research is scheduled to appear in an upcoming issue of Astrophysical Journal.

STORY LINKS

BBC website
Minneapolis Star Tribune story

Aug
08
2007

So clear, you can taste the cheese: This image from the Apollo 15 mission is presented here with less than 1% of the resolution the new scans will offer.  Image from NASA / University of Arizona.
So clear, you can taste the cheese: This image from the Apollo 15 mission is presented here with less than 1% of the resolution the new scans will offer. Image from NASA / University of Arizona.

The University of Arizona is working with NASA to put all the original photographs from the Apollo moon missions on-line, free and available to the public. The original images have rarely been seen—they are irreplaceable, so NASA keeps them under lock and key in a deep-freeze. Fuzzy, second-generation prints is all most of us have ever seen.

But now, thanks to digital technology, high-resolution scans can be made. And I do mean high: resolution will range up to 200 pixels/mm (the Internet displays pictures at about 3 pixels/mm), and file size up to 12 gigabytes. The resolution is so fine, you can actually see the original photographic grain.

Some 36,000 images in all will be scanned. The project is expected to take three years to complete.

Aug
08
2007

Mars.  So close, and yet not: Image courtesy NASA and ESA.
Mars. So close, and yet not: Image courtesy NASA and ESA.
So, a friend of mine wrote me the other day to tell me about upcoming spectacular Mars viewing on August 27. Here’s the email:

Two moons on 27 August

Planet Mars will be the brightest in the night sky starting August.

It will look as large as the full moon to the naked eye. This will culminate on Aug. 27 when Mars comes within 34.65M miles of earth. Be sure to watch the sky on Aug. 27 12:30 am. It will look like the earth has 2 moons. The next time Mars may come this close is in 2287.

Share this with your friends as NO ONE ALIVE TODAY will ever see it again.

My thoughts on this email...

This email is not a hoax exactly – but it is a case of once true and now outdated information mixed with bad information arising out of a bizarre “telephone game” like scenario.

Mars was this close to Earth…on August 27, 2003. And looking through a telescope at it at that time it would appear as large when viewed through the telescope as the moon does to the naked eye.

However, this close approach (called an opposition) was only slightly closer than other recent oppositions, which regularly occur every 26 months, and are closest twice every 32 years, alternately at 15 and 17-year intervals, and always between late July and late September.

Learn more about the “hoax” on Snopes.

Jul
11
2007

Venus and Mars are alright tonight: They may not teach us much about conditions on Earth, but they provide hours of entertaining temperature conversion!  Photo of Venus (left) from NASA; photo of Mars (other guy) from the Library of Congress.
Venus and Mars are alright tonight: They may not teach us much about conditions on Earth, but they provide hours of entertaining temperature conversion! Photo of Venus (left) from NASA; photo of Mars (other guy) from the Library of Congress.

As Science Buzz's resident global warming skeptic, I've taken a lot of shots at Al Gore over the years. Today, however, I find myself in the unusual position of having to defend him against unfair attacks. Somewhat.

In an editorial last Sunday, Gore stated:

“Consider this tale of two planets. Earth and Venus are almost exactly the same size, and have almost exactly the same amount of carbon. The difference is that most of the carbon on Earth is in the ground - having been deposited there by various forms of life over the last 600 million years - and most of the carbon on Venus is in the atmosphere.

As a result, while the average temperature on Earth is a pleasant 59 degrees, the average temperature on Venus is 867 degrees. True, Venus is closer to the Sun than we are, but the fault is not in our star; Venus is three times hotter on average than Mercury, which is right next to the Sun. It's the carbon dioxide.”

This got a bunch of bloggers to thinking. George Reisman went to a NASA website and found an interesting comparison:

PLANET Venus Earth Mars
CO2 IN ATMOSPHERE 96% 0%* 95%
AVERAGE TEMPERATURE 867˚F 59˚F -81˚F

*Not quite true: Earth’s atmosphere is 0.035% CO2.

So, planets with lots of carbon in their atmosphere can be either broiling hot or icy cold.

(Another writer, Evan Kayne, complained (seventh item) the comparison isn't fair; Reisman didn’t take into account the fact that the atmosphere on Mars is only 1.3% as thick as Earth’s. James Taranto of the Wall Street Journal re-did the calculations, and concluded that frigid Mars still has 34x as much CO2 per cubic foot of atmosphere as the Earth does.)

So far, Al isn't looking too good. But then, blogger David Downing thought he'd discovered another problem. According to the NASA site, Mercury has an average temperature of 452˚ Kelvin, while Venus has an average temp of 726˚ Kelvin. That’s only 1.6 times hotter, a far cry from what Gore had claimed!

Wait a minute. What’s this “Kelvin” scale and why is Downing using it? Well, all temperature scales measure energy. And on the Kelvin scale, 0 degrees means “no energy AT ALL.”

This makes it very easy to compare the energy in different systems. In Celsius, 0 degrees doesn’t mean “zero energy;” it means “the amount of energy in frozen water” -- which may seem chilly to you and me, but at a molecular scale, it’s got plenty of heat. (0 degrees Fahrenheit is apparently the amount of energy in a mix of ice, water, and ammonium chloride.) Comparing 25˚F to 50˚F is tricky, because the scale doesn't stop at 0. As any Minnesotan knows, it goes wayyyyy lower than that!

(It’s kind of like saying “Mike is five years older than me; Vic is 10 years older than me; therefore, Vic is twice as old as Mike.” That would only be true if I were 0 years old. If I were, say, 47, then Mike would be 52 and Vic would be 57, and the differences would be much less impressive.)

So, Downing assumed Gore must have been working in Fahrenheit, and believed that if Venus is 867˚F and Mercury is 289˚F, then Venus is three times hotter. Ha ha, what a silly mistake! I was all prepared to poke fun at Al for this glaring error, until I realized – Mercury isn’t 289˚F. According to NASA, it’s a toasty 354˚F.

So, where did Al get 289˚F? I looked in a bunch of sources -- no one was even close. Wikipedia listed Mercury at a mere 26˚F. (The side facing the Sun broils; the side turned away freezes; this is an average.)

But then I noticed -- 26˚F is 270˚K. And Wikipedia lists Venus at 735˚K . Using the proper Kelvin scale, that works out to 2.7 times hotter than Mercury. Not quite 3 times, but in the ballpark. And, to be fair, Wikipedia gives Mercury a range of temperatures, and “3x hotter” fits comfortably within that range.

So, it turns out Gore was closer to being right than he’s given credit for. He WAS working in the proper Kelvin scale. He was just relying on figures from Wikipedia rather than from NASA.

I don’t know if all this has taught us anything about global warming. But man, have I learned a lot about planetary atmospheres, temperature scales, and math! Thanks, Al!

UPDATE: Evan Kaye had claimed that the atmosphere on Mars is only 2% as thick as Earth's. James Taranto, using figures from the NASA site linked to above, calculated that it is actually 1.3% as thick as Earth's. We have corrected the figure.