Bad Astronomy Blog

Global Vaccination Week: Are You Up to Date?

15 hours 5 min ago

Are you up to date with your vaccinations?

That’s the theme of this year’s Global Vaccination Week (Apr. 24–30, 2014), a big health effort by the World Health Organization. The goal: Save millions of lives, many if not most being children’s.

Yes, you read that right. Estimates are that vaccines save about 8 million lives every year. Measles alone kills more than 100,000 people every year worldwide … and that number was a terrifying 2.6 million deaths before 1980, when the vaccine was introduced. Just from measles. Measles, a disease that is so rare nowadays that in the United States fatalities are almost unheard of.

That’s because of vaccinations. More than a billion children have been vaccinated against measles since the year 2000, and deaths have dropped by nearly 80 percent.

Vaccines work. Smallpox killed hundreds of millions of people in the 20th century. By 1978 it was gone. Why? An intensive global vaccination effort wiped that scourge off the planet. There hasn’t been a case in the wild since 1977.

The list goes on. Polio, diphtheria, pertussis, and more—terrifying diseases, and in general ones that attack children more than adults—are all on the decline globally due to vaccinations. But we can do better.

Vaccines of course help prevent you from getting infected, but they also help lessen the severity of an infection if you do wind up getting sick anyway. And through herd immunity they also help prevent infections of people who cannot get vaccinated (very young infants and immunosuppressed folks, mostly). I’m all for saving the lives of babies.

And yet, despite this mountain of evidence and long history of success, anti-vaccination efforts continue apace. Jenny McCarthy, perhaps the best known mouthpiece of vaccine misinformation, claims she’s not anti-vax in a shameless op-ed (and has her head handed to her for it). Actress Alicia Silverstone has jumped on that bandwagon in a recent book on parenting. In Denver, a bill making it harder for parents to opt out of vaccinations for their children was shot down.

I hate that this has happened the way it did, but some moms are speaking out due to losing a child, like Shannon Duffy Peterson, whose daughter Abby died at the age of 6 from complications due to chicken pox. My friends Toni and David McCaffery lost their daughter Dana at the age of four weeks to pertussis and are now vocal public advocates for vaccination. Deb Proctor had one child suffer a brief reaction to a rotovirus vaccine, but her two other children (as well as she herself) contracted pertussis, whooping cough. She’s lived through both sides of this, and now strongly supports vaccinations.

We need to make sure people are aware of the facts of vaccinations, both for adults and children.

And that leads us back to the Global Vaccination Awareness week. Are you up to date on your vaccines? I am. My wife is as well, and so is our daughter (who is attending college next year, and has to prove she’s vaccinated to enroll). This is as good a time as any: Go see your board-certified health practitioner, and find out if you need boosters.

The life you save may be your own. Or it may be an infant up the street, or a cancer surviving co-worker with a low white blood cell count, or just some innocent kid whose parents decided to opt out based on bad information. It’s up to all of us to do what we can to protect the health of all of us on this planet.

Do what you can.

For Hubble’s 24th Birthday: A Stellar Nursery Being Destroyed by the Stars It Created

19 hours 5 min ago

Today marks the Hubble Space Telescope’s 24th birthday; on this day in 1990 the Space Shuttle Discovery roared into space with Hubble in the payload bay, and the next day astronaut Steve Hawley deployed the telescope into orbit. For years a flaw in the mirror degraded the resulting observation but upgrades to the cameras onboard the observatory compensated, and ever since Hubble has been wowing astronomers and the public alike with its grand view of the Universe.

Every year on or about this date, the folks at the Space Telescope Science Institute release a gorgeous image to celebrate (see Related Posts below). This year is no exception; in fact, this year’s is one of the best: NGC 2174, a vast stellar nursery being blasted away by the ferocious light and heat of nearby stars.

[Click to embiggen, or get the even vastier 1860 x 1860 pixel version.]

Holy wow! NGC 2174 is about 6,000 or so light years away toward the constellation of Orion, and is a huge cloud of gas and dust enthusiastically forming stars at a brisk clip. And I do mean huge: Even at that terrifying distance, the entire cloud is as big in the sky as the full Moon. This small section of it seen by Hubble is a half-dozen light years across all by itself, and the whole cloud is more than 10 times larger.

The gas and dust in NGC 2174 have been forming stars for millions of years, and it is populated with quite a few young, massive, hot, and very luminous ones. Just off to the right in the picture, outside the field of view, is a whole cluster of them. These stars are so bright that their light and winds of subatomic particles are eating away at the cloud, dissolving it. What you’re seeing here is the edge of that erosion front, the border between material already blown away and material that is soon to be destroyed by it.

This region is studded with bumps and long fingers of material; these are denser knots where stars are forming deep within. The gas and dust are thicker here and resist erosion. The knots act like sandbars in a stream, forming graceful arcing heads upstream and long tails pointing away from the hot stars. The very edges of the heads are glowing as they undergo the onslaught from the nearby superstars, creating a bright limb around them.

I can’t help but think they look like sperm (though we’re talking gametes a trillion kilometers long …). The metaphor isn’t a bad one, since these are the sites where stars are being born. And it’s a race to see which knots can actually birth their stars before being blown away by the winds. The similarity in shape is due to similarity of forces; both are sculpted by hydrodynamics, the motions of fluids. On the microscopic side sperm get an advantage by being sleek and streamlined so they move more efficiently through a fluid; on the cosmic side the knots get sculpted as the fluid flows past them. Animal birth, star birth: The motion of the medium is relative.

One last thing I want to point out, too. In the detail shot above you can actually see a few background galaxies. That’s amazing! The dust littering NGC 2174 is very efficient at absorbing light, and it’s rare to see more distant objects in pictures of star-forming regions. In this case though we have an ace in the hole: This image was made using infrared filters!

Infrared light is better at getting through the dust, so some galaxies are able to pierce the muck. Note that as you look more to the left in the big Hubble image you see fewer stars and galaxies, and things get redder. The really thick dust is on the left, and it blocks almost everything behind it. But some of the stars embedded in the dust manage to get their reddest light through. I can still spot a handful of galaxies there; I imagine these are very luminous beasts indeed to be able to shine through, pouring out infrared light. Perhaps they themselves have huge clouds like NGC 2174, vigorously forming stars and blasting infrared light out into the Universe, and it’s that glow we see here.

The Universe is very meta sometimes.

Anyway, happy birthday, Hubble! It was a pleasure to work on you for all those years, and even more of a pleasure to continue writing about your exploits now, nearly two and a half decades after you got your start.

Related Posts

Hubble’s Knight to Remember (2013, 23rd)
A Stunning Star Factory for Hubble’s 22nd (2012, 22nd)
Happy Birthday, Hubble (for Real This Time) (2011, 21st)
Hubble Celebrates 20 Years in Space With a Jaw-Dropper (2010, 20th)
Hubble’s Fountain of Youth (2009, 19th)
When Galaxies Collide (2008, 18th)
Hubble’s 17th: Chaos, Birth, and Near-Death (2007, 17th–worth it for the last image alone)
Happy Birthday HST! (2006, 16th)
Hubble’s Anniversary (2005, 15th)

Hubble Drills Deep Into the Universe

Wed, 04/23/2014 - 09:00

What happens when you take a 2.4-meter telescope, launch it into space, and command it to stare at one spot in the sky for a solid 14 hours, taking data both in visible light (like our eyes see) and infrared?

This. This.

Can I get a “Yowza!” from the congregation? No? Maybe that’s because when I shrink this Hubble Space Telescope picture down to fit the blog you can’t really get a sense of what you’re seeing here. So click the picture to get the 1280 x 1280 image, or better yet, do yourself and your eyeballs a favor and take a poke at the huge 3900 x 3900 pixel version, because holy wow.

What you’re seeing here is a view of thousands of galaxies. Thousands. Sure, there are some stars in our own Milky Way punctuating this picture here and there but they are few, and just stomped flat by the number of whole galaxies you’re seeing. The stars can be distinguished from galaxies because they’re point sources; small dots. They also might have those lines going through them called diffraction spikes. Galaxies don’t usually get those because they’re fuzzier, spread out over many pixels. That suppresses the diffraction spikes.

So for example that bright point with pretty spikes you see toward the upper right is a star, probably a few thousand light years from Earth. That’s a long way to be sure, but even the nearest galaxies you can see in this image are hundreds of millions of light years away! Some are billions; the most distant object in this shot are at least 9 billion light years distant. That’s a million times farther away than any star in the picture.

When the light we see here left those galaxies, the Sun hadn’t yet formed. When the Earth itself was coalescing from countless specks of dust, that light still had half its journey here ahead of it.

So yeah. This stuff is far.

In fact you’re seeing galaxies at all different distances from Earth in this image, but the observation itself was taken to look at the cluster of galaxies in the center. Called CLASS B1608+656, it’s a clump of galaxies about five billion light years away. The mass of that cluster acts like a lens, bending space, magnifying objects behind it. This gravitational lens has distorted and amped up the brightness of a luminous galaxy located an additional several billion light years behind it, creating the weirdly shaped mess you see in the close-up above. Rings and arcs are common in such events.

But there’s so much more to this image; just scanning across it reveals an incredible variety and diversity of galaxies. Remember, too, you’re looking at objects as they existed eons ago; many are still growing, suffering collisions with other galaxies, giving them fantastic shapes. As an example, I’m fond of this little group near the top of the main image:

I’m not precisely sure what to make of this. The bigger galaxies look to all be about the same distance from us, but that could be a coincidental alignment. Some of the galaxies are blue and clumpy looking, indicating they’re aggressively forming stars (hot, young, massive stars are preferentially blue), while some are quite red. The red ones may be very dusty, which reddens the light from stars, or they may be farther away, their light redshifted as it fights against the expansion of the Universe itself, losing energy along the way. It may be a mix of both. Unfortunately, this image was made using only two filters, so colors can be difficult to interpret, and don’t yield a lot of subtle information. The only way to know more about the galaxies would be to measure their distance, and I didn’t find anything in the literature about them.

That’s worth taking a moment to ponder, actually. These are entire galaxies, collections of tens of billions of stars, planets, dust, and gas clouds, each and every one a monstrous object on scales that dwarf our everyday experience … yet there are so many of each of them in this image alone we can’t possibly know their details. We can determine their coordinates on the sky, get a rough estimate of their distance, but there is simply no way to get a measure of them as individuals. They are too many. It’s like trying to get the life history of everyone who passes you on a busy New York City street corner. The task is too overwhelming.

And just in case I have not yet crushed your puny human mind, this image represents a tiny fraction of the entire sky; perhaps only one ten-millionth of it. That means there are hundreds of billions of galaxies like these scattered throughout the Universe.

So gaze again at that image, one that drills a narrow but incredibly deep view through our cosmos, one that shows us both the awe-inducing grandeur and soul-squeezing immensity of it, and remember: The Universe is far, far larger than this still.

And yet here we are, pondering it. To those galaxies, we are the ones who are lost in the anonymous throng. Yet I would argue we are as important and interesting a piece of the Universe as any other we can imagine. We are part of it at the same time as we study it, and to me, that is part of what makes us great.

Black Skies, Smiling at Me

Wed, 04/23/2014 - 04:30

This week, April 20–26, 2014, is International Dark Sky Week, a global effort to get people to appreciate the skies above them. Light pollution—excess light thrown into the sky by street lights, houses, buildings, and pretty much everything that makes light—reduces our ability to see the stars, sometimes dramatically. I lived in Chicago for a year, and on the clearest nights I could only see the very few brightest stars, struggling against the mighty orange glow of the city projected upward.

This light is wasted; it’s money thrown away, it’s low-efficiency, and in many cases the lights being used at night aren’t really doing a good job of illuminating the ground and making it safer.

Astrophotographer Mark Gee (who has been featured on my blog before; see Related Posts below) made a short and lovely video to highlight the issue. His work is stunning and well worth your time.

Years ago, my wife and I took a weekend vacation to a campground in rural Virginia; it was a camp I attended a couple of times as a kid. The owners were family friends, and one weekend every year they had old friends over to spend time together and enjoy the gorgeous scenery.

We parked near the main house, and as we fussed inside the car getting our belongings together, another weekend-goer walked by us while he talked on his phone. We overhead one snippet of his conversation, where he said “… and you should see the sky at night here. It’s so dark, and there are thousands of stars!”

I turned to my wife and we smiled at each other. He had no idea an astronomer was sitting there and could hear him; that was a spontaneous exclamation from someone who simply had never seen a dark sky before, and was properly overwhelmed by it.

That night we all sat in a field and watched the brilliant stars sparkling in a field of velvety black. It truly was amazing, mesmerizing, surpassingly beautiful. The artwork of nature, displayed for all to see …

… who have the skies to see it. This experience is what light pollution is stealing from us, and this is why I support what the International Dark Sky Association is doing to raise awareness of it. They have a different theme every day this week talking about our brightening skies, and I encourage you to take a look to see what they’re doing about it. The sky belongs to all of us, and we all deserve a chance to see it.

Related Posts

Silhouettes and Moonrise in Real Time (Mark Gee video)
Milky Meteor
Well, At Least Light Pollution Makes for a Pretty Photograph
Stunning Picture of the Milky Way … Over Los Angeles?
The Skies at Night Are Too Darn Bright
GLOBE at Night Wants You to Look Up!

10 Planetary Facts for Earth Day 2014

Tue, 04/22/2014 - 04:30

Today is Earth Day, a worldwide celebration of our home planet. I know you’ll be hearing a lot of talk about the environment today, humanity’s global impact, and more … which is great, and I wholly support that conversation (obviously).

But as an astronomer and science dork, I do love me some fun factoids. So I gathered together/calculated a few to give you a better appreciation of our planet’s place in the Universe. You might want to check out the ones I posted last year, too. You can’t know too much about Earth.

1) Earth Day is April 22 every year. On average (jumping over leap years and such), between subsequent Earth Days our planet moves about 940 million kilometers (580 million miles), the circumference of its orbit around the Sun. That means it’s faster—way faster—than a speeding bullet: about 30 km/sec (18 miles/sec)! Typical rifle bullets travel 1-2 km/sec, so the Earth outpaces them handily.

[UPDATE (Apr. 22 at 18:00 UTC): I'm getting some comments about this, mostly referring to how I measure that speed. Implicit in my words is that I meant relative to the Sun, so that's how quickly the Earth would move around the Sun. In general, the speed of the Earth (or anything) depends on what you're measuring its speed against. Since I'm on Earth, it's not moving at all relative to me, and if you're in a distant galaxy we're moving away at a large fraction (or even faster than) the speed of light. All motion is relative... you can quote me on that!]

2) It’s not a small world after all. The surface area of the Earth is about 510 million square kilometers, or 197 million square miles. It’s not a perfect sphere (see listing No. 4 here), but if it were, using the surface area to find the Earth’s diameter would give you a ball 12,742 km (7,900 miles) across.

3) The Earth is the biggest of the terrestrial (rocky, as opposed to Jupiter-like gas giant) planets in our solar system.

4) Venus, the closest planet in the solar system to Earth’s size, has a diameter of 12,104 km (7,504 miles), 95 percent the width of Earth. It has about 82 percent the mass of Earth, too, making it our twin. However, its thick atmosphere is mostly carbon dioxide, it rains sulfuric acid, the air pressure on its surface is 90 times Earth’s, and the average temperature is a lead-melting 460 C (860 F). So it’s more like our evil twin.

5) Nearly 2,000 confirmed exoplanets (worlds orbiting other stars) have been found so far. The smallest, Kepler-37b, is barely bigger than our own Moon! Another, KOI-314c, has the same mass as Earth but is so hot it’s puffy, with a huge atmosphere. The planet that has the best chance of being most like Earth is Kepler-186f, which has 1.1 times the Earth’s diameter and is the right distance from its star to have liquid water. We really don’t know what it’s like beyond that, though. It might be more like Venus, or Mars.

6) We’ve only just started looking for other planets, though. There may be billions of Earth-size planets in our galaxy alone.

7) Coming back home again, Earth has something no other planet we know of has: a lot of water on the surface. It’s about 71 percent water by area, dominated by the Pacific Ocean, which covers a staggering 155.6 million square km (60 million square miles) of the surface. That’s nearly a third of the planet.

8) Most of the Southern Hemisphere (by a long shot) is covered in water: About 80 percent of the planet’s area south of the equator is water. North of the equator it’s about 60 percent.

9) Water exists naturally in all three physical states on Earth’s surface: solid (ice), liquid, and gas (water vapor). Due to a peculiar property of water—called its triple point—it can even exist in all three states at the same location and time. So now when things go wrong, you can say, “Well it could be worse: It could be raining and snowing and steaming!”

10) The more we look, both in our neighborhood and in deep space, the more we find that our Earth is one-of-a-kind. Even if we do eventually spot those billions of other planets similar in size to Earth, it’s unlikely they will be just like ours, with our exact balance of chemistry, temperature, and life. Heck, in the distant past the Earth didn’t look like it does now, and it’s the same planet.

What this tells us is that what we have now is precious, unique, and vital to us and ours. We don’t have an emergency backup, a summer home, a spot we can retreat to. The Earth is all we’ve got. We need to treat it that way.

Slate Plus You

Mon, 04/21/2014 - 08:06

I’ve been writing for Slate for about a year and a half now, and one thing I like about the magazine is that it’s all online; there’s no print version. That means there’s not a lot of baggage leftover from print media (which a lot of bloggers—including me sometimes—call “old media”). The folks behind the scenes have been working the ‘Net a long time and know their way around.

That means they’re also willing to try new things, and we’re rolling one out now that I think looks pretty interesting: Slate Plus. This is premium content, added material, including podcast extras, interviews, early access to Slate events, behind-the-scenes stuff, and more.

Our fearless leader, David Plotz, explains what this is all about, but in a nutshell Slate Plus is a membership program; monthly access is $5, and yearly is $50. Mind you, this is not a paywall; Slate will still be free, and you need pay nothing for the usual yammering from me and all the other writers here you’ve been seeing all along. But Slate Plus has more stuff and more access. There’s a free trial for two weeks you can try if you take a look now.

If you do want to sign up, I ask you use this link to become a member of Slate Plus. Why? Well, for one thing, if you do you'll get a $5 credit, essentially a month for free. So yay!

Also, we’re running a contest among Slate staff and contributors to see who can gather the most sign-ups, with a tidy (if modest) monetary award going to the top hunter/gatherers. I have no clue if I will place in the top tier or not, but if I do, I will donate that money to DonorsChoose.org, which is like a KickStarter for school science funding. Teachers in undersupported schools put together projects for their kids and ask for donations from the public. This is a great organization doing a lot of good for students all over the U.S., so I’ll be happy to send some filthy lucre their way if enough of my droogs here sign up for Slate Plus.

So give it a shot! I’ll note that we’re still trying to figure out what I can do to contribute to Slate Plus as well. Maybe you should tell me what you’d like to see! An interview every now and again, a light-hearted debate with another Slatester, a video tour of my ridiculously entropic home office? Leave a comment and let us know!

And, as always, thanks for reading my blog. With or without Slate Plus, it’ll be right here where you left it, don’t worry.

A Dragon Chases the Space Station

Mon, 04/21/2014 - 04:30

I post a lot of images taken with some pretty nice astronomical gear, from “amateur” telescopes up to multibillion dollar space observatories.

But it doesn’t always take a lot of fancy equipment to get great shots. Sometimes it just takes a camera, a tripod, and a little foreknowledge.

Armed with just this, astronomer Bill Longo took the image above from his observatory outside Toronto. It’s a stack of eight 30-second exposures for a total of four minutes using a Canon T3 camera and a 6.5mm lens.

It shows the night sky facing west, with the bright winter stars of Auriga and Gemini setting, with the amazingly bright planet Jupiter punctuating the twins’ belly. And that bright streak seemingly bisecting Jupiter? Why, that’s just the International Space Station moving across the sky, its 100-meter length reflecting sunlight down to Earth.

And if you look very carefully, just under the ISS trail is a much fainter one: That’s the SpaceX Dragon capsule chasing down the station. This picture was taken on April 19, 2014, just hours before the private spaceship met up with ISS and was successfully grappled to its berthing point. Longo provides an annotated version of the picture that’s helpful:

Imagine! Six astronauts from around the world are in that bright streak, and were about to grapple an American spacecraft using a robotic arm built in Canada, so they could bring aboard a new round of scientific experiments, food, and supplies for their stay on board a working space station that’s been in orbit around our fair world for more than 5600 days. And it’s bright enough to not only be seen from the ground, but easily seen, and photographed with equipment you can pick up at a local store.

You can keep your flying cars and hoverboards. We live in the future, now, and all you have to do to prove it is go outside look up.

Tip o’ the lens cap to Bill Longo for sending me his photo.

Happy Easter SUN Day!

Sun, 04/20/2014 - 04:30

Today is Easter Sunday, a Christian holiday. It actually has a tie-in with astronomy, since it’s celebrated on the first Sunday after the first full Moon after the March equinox. The equinox was March 20, and the full Moon was Monday (during the lunar eclipse, not so coincidentally), so here we are.

As is the case with most holidays in America, there’s a secular component to it as well. In this case, the Easter Bunny (which originated in Germany, incidentally) started out with religious connotations, but now resembles more of a lagomorphic Santa Claus.

Whatever the origins, and whatever your beliefs, I think we can all agree that it’s fun to bite the ears off a chocolate bunny first (and/or perform hideous experiments on Peeps). So with an eye toward the astronomy and a tongue firmly in cheek, I present to you a picture of the Sun taken by astrophotographer Göran Strand:

What you’re seeing there is the edge of the Sun to the upper right, and a detached prominence to the lower left. A prominence is a huge blast of solar gas blown off the Sun by intense magnetic fields; usually these are connected to the Sun’s surface but sometimes become detached. It’s almost as if it…

[takes off sunglasses]

… hopped off the Sun.

Also, to give you an idea of its size, Strand included a picture of the Earth … the shape of which he changed to match the theme.

Or maybe Strand is a Heinlein fan. After all, it was he who once wrote, “The Earth is just too small and fragile a basket for the human race to keep all its eggs in it.”

That’s a fine sentiment for any season.

Note: In the interest of full disclosure, Strand took this photo on Sept. 4, 2013. But how could I resist running it today?

That’s No Moon … Well, Actually, Yeah It Is

Sat, 04/19/2014 - 04:30

So there’s a picture you don’t see every day. Clearly, Vader’s forces were not at all happy about the lunar eclipse. 

I know, it really does look like the Moon was shooting out a laser at a passing ship, but that’s an illusion: In fact, that laser is hitting the Moon, and it was sent from Earth.

While you and I were busy watching the total lunar eclipse on Monday, a bunch of astronomers were zapping it with high-powered lasers. They do this every now and again to find out exactly how far away the Moon is (and to provide yet another test of relativity).

Apollo astronauts left a series of retroreflectors there, devices that are designed to reflect light back in exactly the same path it came in. If you shoot a retroreflector with a laser, the beam will come back directly at you. Over the course of 800,000 kilometers (500,000 miles) to the Moon and back the beam spreads out a lot, so a telescope is used to collect the photons from the laser.

Since we know the speed of light very accurately, the time it takes for the beam to hit the Moon and come back tells us its distance. Think of it this way: If you are traveling at exactly 100 kilometers per hour, and you drive for exactly one hour, you know you drove 100 kilometers. Same thing here, but the car is a photon, the speed is the speed of light, and the distance is a wee bit more then you’d go for a family outing.

In this case, the retroreflector was left by the Apollo 15 team. I knew this right away! How? Because this:

Apollo 15 landed on the very eastern edge of Mare Imbrium (the large dark circle; actually a lava plain), near the border with Mare Serenitatis. As you can see, the beam converges right at the Apollo 15 spot. I know it looks like the beam is coming from there, but that’s perspective for you! The beam appears to get smaller with distance, and your eye can’t tell if it’s getting smaller as it heads away, or getting bigger as it comes closer.

Astronomers have been measuring the Moon’s distance for many years, and it’s from that we’ve learned the Moon is moving away from the Earth by about 4 centimeters per year due to the complicated interaction with Earth’s gravity. But today I learned something about this: During a full Moon, the amount of light reflected back from the Moon drops. This was a mystery for quite some time, but it turns out that’s due to the way the mirrors there are set up; the Sun shines down them and heats them up, and they lose their efficiency at reflecting light back to us. During an eclipse, though, the Earth blocks the Sun during the full Moon, so the mirrors don’t heat up. They reflect light back to us just fine, proving that solar heating was the problem.

It’s funny to think that while I was collecting photons to make photos and video of the Moon, astronomers a thousand kilometers south of me were sending photons to the Moon … and getting them back.

Tip o’ the X-Wing to Dan Long for letting me use his photo, and to APOD, where I first saw it. I'll note this is at least the fourth time I've used a variation of this headline, and it's funny every flippin' time.

Correction, April 20, 2014: I had originally attributed the photo incorrectly to Tom Murphy, who works on the ranging experiment.

Incredible: SpaceX Dragon Capsule Video Taken From the Ground!

Fri, 04/18/2014 - 18:07

Update, April 19 at 15:00 UTC: Several people on Twitter have pointed out that what is seen in this video is most likely not the capsule and deployed arrays, but actually the upper stage of the Falcon 9 rocket and the ejected solar panel covers. That does seem likely to me given the scale of the objects, so I have sent Legault an email asking him about it, and I will update this post again when I know more.

Correction, April 19 at 15:15 UTC: Aha! Yes, I do now think what we are seeing here is the upper stage of the Falcon 9, the Dragon capsule, and the two solar panel covers (used to protect the Dragon's panels during launch, and which are ejected before the panels are deployed). What I somehow missed at the end of the video are the silhouettes of trees in the distance. That gives a sense of scale to the video; the Dragon capsule itself plus the solar panels would be far smaller than seen here. Also, around 30 seconds in you can see the stars of the Big Dipper in the background, showing the field of view of this video is far larger than I had originally supposed.

So to be clear, this is NOT just the capsule and solar panels, it is a larger set of objects that are physically separated in space by quite a bit, making it much easier to photograph them. This is still a cool video, but it isn't the technical achievement I first assumed. I have struck through the original text below and added the correct info.

Thierry Legault is a gifted astrophotographer renowned for his footage of the International Space Station and (once upon a time) the Space Shuttle that he takes through his telescope. His ability to capture these rapidly moving objects is nothing short of spectacular, and I always think there's no way he can top what he's already done.

Then I see this: Video of the SpaceX Dragon capsule in orbit a mere 25 minutes after launch!

Incredible. This is seriously amazing work; being able to spot the capsule, get it framed up, and then to track it by hand as it glides over France less than a half hour after launch? Holy wow. You can actually just make out the capsule itself, and the extended solar panels on either side (those power the Dragon for the two or so days it takes for it to catch up to the space station). To give you a sense of scale, the capsule is 7.2 meters (24 feet) long and 3.7 meters (12 feet) wide. The panels are about 16.5 meters (55 feet) across. It was roughly 370 km (230 miles) above the Earth's surface when he shot this.

What you're seeing here is wide-angle footage, showing the upper stage of the Falcon 9, the Dragon capsule, and the ejected solar panel covers moving along together in orbit around the Earth. This was taken a few minutes after the capsule separated from the rocket upper stage, so all the individual things you see here were still near each other in space. Over the next two days the capsule itself will "catch up" the space station and be grappled on Sunday.

So yeah Legault is the best. I've written about his work, many, many times; go read it. Trust me here: You'll be astonished at what people can do when they're at the top of their game.

Congrats to Thierry for this achievement, and to SpaceX for another successful launch!

SpaceX Launch Update: Next Attempt Is Today at 19:25 UTC

Fri, 04/18/2014 - 07:08

Update, April 18 at 19:40 UTC: The Falcon 9 lifted off on time at 19:25 UTC, and the launch went perfectly. Just under 11 minutes later the Dragon capsule was deployed into orbit. The solar arrays were deployed, and all looks good. Congrats to SpaceX! Also, if you have clear skies over the next two days, you can look for the capsule catching up to the ISS yourself. I suggest using Heavens-Above (you need to enter your location) to get pass predictions.

Quick update: SpaceX is go today at 19:25 UTC (3:25 p.m. EDT) to launch a Falcon 9 rocket to the International Space Station. The Dragon capsule atop the rocket is loaded with supplies and experiments for the astronauts orbiting the Earth. If it launches on schedule, it will rendezvous with ISS and be grappled on Sunday, April 20 at 11:14 UTC.

A launch attempt on April 14 was aborted due to a helium leak in a valve that is involved with the first stage separation after launch. The valve has been replaced. The big problem now is weather; it’s not looking great. If the launch is delayed again, the next attempt will be Saturday, April 19 at 19:02 UTC (for an ISS meetup and grapple on April 22).

You can read more about this mission in my first blog post about the launch. You can watch the launch live on the SpaceX webcast or on the NASA Ustream channel.

An Astronomical Discovery: Earth-Size Planet Found in Its Star’s Habitable Zone

Thu, 04/17/2014 - 11:09

I have some cautiously exciting exoplanets news: Astronomers have announced the discovery of a planet that is very nearly the same size as Earth and orbiting its star in the habitable zone—that is, at the right distance from its star to have liquid water on its surface. We don’t know how Earth-like it is, but this shows that we’re edging closer and closer to finding another Earth, and this one is the best bet we’ve found so far.

The planet is called Kepler-186f and was discovered using the Kepler Space Telescope, which was designed to look for planets orbiting other stars. Kepler exploits what’s called the transit method: It stares at 150,000 stars all the time, looking for dips in the amount of light received from every star. The idea is that if a star has planets, and if we see the orbits edge-on, then every time the planet passes between us and its parent star it’ll block an teensy bit of light (usually far less than 1 percent).

This method is extremely powerful—about a thousand planets have been found this way in Kepler data! In fact, most of the planets found this way have been from Kepler. Another cool thing is that if you know how big the star is (and we generally do) then you can also determine the size of the planet by how much light it blocks.

Kepler-186f is one of the big success stories. It’s part of a mini-solar system, a five-planet system orbiting a red dwarf: a smaller, cooler star than the Sun. The other four planets (Kepler-186b-e) are all very roughly Earth-size, but orbit far closer to the star, ranging from 5.1 million kilometers (3.2 million miles) to 16.5 million kilometers (10 million miles)—for comparison, Mercury orbits the Sun at a distance of about 50 million kilometers (31 million miles), so this really is a solar system shrunk down. But even though the star is cooler than the Sun, these planets are close enough to it to be pretty hot; even the farthest of the four previously known would be hot enough to boil water on its surface (assuming it has a surface).

186f is different, though: It orbits farther out, about 53 million kilometers (33 million miles) from the star, where temperatures are more clement. Making some basic assumptions, it lies near the outside edge of the star’s “habitable zone,” where liquid water can easily exist on the surface of a planet. We know of several dozen planets like that in the galaxy so far, but what makes 186f special is its size: it’s only about 1.1 times the size of Earth! Together, these make it potentially the most Earth-like planet we’ve yet found.

I say potentially because honestly we don’t know all that much about it besides its size and distance from its star (and its year—it takes 130 days to orbit the star once). The next things we’d need to know about it are the mass, what its atmosphere is like, and the surface temperature. The gravity of the planet depends on its mass, and in many ways the atmosphere depends on the gravity. Unfortunately, we don’t know either, and we’re unlikely to. The techniques used to find planet masses aren’t up to the task for this planet—the star is too dim to get reliable data. The same is true for any air the planet might have as well. And without that, we don’t really know its surface temperature.

So we don’t know if this planet is like Earth, or more like Venus (with an incredibly thick, poisonous atmosphere that keeps the surface ridiculously hot), or like Mars (with very little air, making it cold). It could be a barren rock, or a fecund water world, or made entirely of Styrofoam peanuts, or some weird thing we haven’t even imagined yet.

Still, our models of how planets form are getting better, and we’re getting a handle on how they behave. According to what we know, it’s most likely that Kepler-186f is a rocky planet like the Earth, with a similar surface gravity. That in turn implies it could have water. But again, we just don’t know, and anything beyond this is speculation; there are a lot of factors in making a planet habitable. As a random one, it may take a magnetic field to make a planet livable. Ours protects us from the constant stream of subatomic particles the Sun emits, which, over several billion years, would have eroded away Earth’s atmosphere. That may be what happened to Mars.

To be fair, I’ll note that there is one planet found before that’s roughly the size of Earth (though bigger than Kepler-186f) and in its star’s habitable zone, but in that case the planet orbits at a distance where it receives about as much heat and light from its star as Venus does from the Sun … and look where that got Venus. Kepler-186f is therefore more likely to be Earth-like than that other planet, though again we can’t be sure with the information we have now.

Still, this is exciting news—after all, one of the main mission objectives of Kepler was to do just this: find an Earth-sized planet in its star’s habitable zone. So, my congrats to the team of astronomers involved: It’s very nice indeed to see a spacecraft achieve its goal! And there’s still lots and lots of data to go through from Kepler. There could easily be many, many more such worlds hidden in the blips of starlight Kepler has returned to Earth.

We’re pretty sure there are billions—billions—of Earth-sized planets in the galaxy. We now know of four that are in their star’s habitable zone (if you include Venus and the other planet I mentioned)… and we also know that some worlds are outside the strict definition of the HZ and yet still have liquid water (Jupiter’s moon Europa and Saturn’s moon Enceladus).

We’ve only just started looking. Who knows what else is out there?

Tip o’ the Lyot stop to Stephen Kane (one of the astronomers who found this planet, for his gracious help with info; go check out his website, Habitable Zone Gallery) and to the lead author Elisa Quintana.

Look! It’s a Car on Mars!

Thu, 04/17/2014 - 04:30

Right now, there are five spacecraft at or on Mars (and two more on the way). One of the spacecraft on the surface is of course the rover Curiosity, the plutonium-powered Mini Cooper–size mobile chemistry lab. One in orbit is the Mars Reconnaissance Orbiter, equipped with the fantabulous HiRISE camera, capable of seeing objects a half meter across on the Red Planet.

Hey! Curiosity is bigger than a half meter. A lot bigger. Can MRO see it?

Why yes. Yes it can.

Can you find the rover in the picture? Hint: Follow the wheel tracks, which you can clearly see.

Holy wow. I love pictures like this. And there’s great value to them, too. Curiosity has cameras on the surface, several in fact, which map out the area in great detail. But we need an overview as well, just like it helps to have a map when you’re out driving. With eyes in the sky and on the ground we get both.

So what was Curiosity seeing at the time this photo was snapped from above? This:

Compare that to the picture above.

Curiosity had stopped at a location called the Kimberley, which consists of quite a few interesting rock outcroppings. Centered in that shot is a five-meter high butte nicknamed Mount Remarkable (off to the left is the direction it was looking when it saw the still-unexplained light). The rover is still on its way to Mount Sharp, aka Aeolis Mons, its ultimate destination. It’s already covered several kilometers of the trip.

Amazing. I’ve had worse maps with me on trips, and here we are marking the exact location of a rover on another planet.

Science! I love this stuff.

Note: I totally stole the title of this post from Bobak Ferdowsi, who will forgive me or else I will shave the rest of his head.

Watch and/or Hear Me Speak at You About Things

Wed, 04/16/2014 - 08:42

I did a couple of interviews recently that I figured I should let y’all know about.

First, I spoke with my pal Desiree Schell on her Science for the People podcast about the recent BICEP2 news about cosmic inflation, as well as the new Kuiper Belt Object that was found in the outskirts of the solar system (I wrote about both stories: here and here, respectively). Desiree also talked to Paul Bogard and my good friend Nicole Gugliucci about other astronomy things in that same interview.

Second, I was in Australia in 2013 to give lots of talks and soak up Aussie culture (and as many Tim Tams and Minties as I cold get my hands on). The very first thing I did after arriving was talk to astronomers Katie Mack and Alan Duffy for their Pint in the Sky video podcast. They split it in to two parts; here’s Part the First:

and here’s Part B:

Basically, I shilled my nerd insult book 27 Nerd Disses: A Significant Quantity of Disrespect (also available on Amazon) that I co-wrote with Zach Weinersmith (and illustrated by Jess Fink) and generally was a smart-ass. But we also talked about other stuff, including how I wended my way down the torturous path to science communication, and what it means to be an astronomer.

These were all fun interviews, so thanks to Katie, Alan, and Desiree for inviting me on!

Also: I'll be in Edmonton, Alberta to give a free public talk about the Mars Curiosity rover called "Where Our Curiosity Has Taken Us" on May 3, sponsored by the Royal Astronomical Society of Canada. So take off to the Great White North, and I hope to see you there!

What Happens When You Throw a Peep Out an Airlock?

Wed, 04/16/2014 - 04:30
Q: What would you hear if you tossed an Easter marshmallow candy out a spaceship’s airlock? A: Not a peep.

Peeps, the wildly popular sugary marshmallow treats, have little nutritional value and take up a lot of space for their mass, so I wouldn’t imagine they’d be a staple food for astronauts. But if some future space voyage stocked them for the astronauts, instead of eating them it might be a lot more fun to throw them out the airlock.

Why? Because this*:

Every year, the Texas A&M University throws the Physics and Engineering Festival, a weekendlong event with dozens of science demos, talks, and entertainment. I was invited to speak in the evening at the 2014 event and spent the day wandering the halls and grounds of the Mitchell Physics Building and Institute, enjoying myself immensely. It was so much fun to see students enthusiastically run their demos to the huge crowd of people who came from all over the Lone Star State.

The Peep demo was one of the first I saw, and one that made me laugh the hardest. It’s funny, but it’s science!

So what did you just see? Peeps are basically spun sugar, starting as a liquid slurry which gets air whipped into it, and then is extruded by a machine into the familiar chick shape. When the sugar solidifies it’s full of little holes, like a sponge. It then gets spritzed with coloring to give it that healthy neon yellow (or in this case, blue) sheen.

In the demo the Peep is placed on a rubbery surface, the glass bell jar is put over it, and the air pumped out. Air expands to fill whatever volume it is in, pushing on the walls of its container until the pressure is balanced. When the air outside the Peep is removed, the air in the little spongy holes expands to replace it. Because the Peep is soft, the material around the holes gets pushed by the air and expands as well, inflating the Peep overall. The tension in the material itself provides a force that keeps the air from expanding into the jar, so at some point the expansion stops when the forces balance.

However, that material is made of sugar molecules all stuck together in a crystalline state. When the Peep expands, the crystal structure is partially broken, and it stays expanded only because the air pressure inside the bubbles is holding it up, balanced by the tension in the sugar. Once the air is let back into the bell jar the air inside the bubbles contracts again, and the material collapses. That part made me laugh even more than the expansion.

Although changed physically, nothing chemically has changed in the Peep, so they’re still edible. Well, by definition, I suppose. That part of the demo is clear enough, though I wonder how many Peeps physics grad student Leo Alcorn, who ran it, ate over the course of the weekend.

Atmospheric pressure here in Boulder, Colo., is about 18 percent less than at sea level, so I hope she avoided any trips to Colorado before she digested them all. Which makes me wonder … are Peeps in Colorado measurably bigger than ones sold elsewhere?

You’re welcome, Colorado parents and students who are looking for a last minute science fair idea.

*I know, I held my phone vertically and not horizontally, against the laws of nature and science and the 'Net. However, there were lots of little kids wandering around, and I figured it was better to orient the phone portrait mode so they wouldn't be included. Also: Tip o' the bell jar to Leo Alcorn, who was awesomely cool about all this.

Blood Moon: The Lunar Eclipse of April 2014

Tue, 04/15/2014 - 10:36

Did you watch the total lunar eclipse last night? Judging from my Twitter feed, a lot of people did! Chatter and pictures were flying around the ‘Net as the silvery full Moon slowly drifted into the Earth’s shadow and turned a lovely shade of orange.

I took the picture above at about 07:21 UTC (01:21 Mountain time, local for me), about 15 minutes after the total phase started. You can see the bright star Spica (the brightest star in the constellation of Virgo) just to the Moon’s lower right, and the much fainter star h Virginis just above and to the left of the Moon. It was fun to see fainter and fainter stars pop up as the Moon faded away, its bright glow no longer capable of washing them away.

Over the course of an hour and a half I took some video using my camera (a Canon T41 with a 250 mm lens), so, for your eyes’ and brain’s pleasure, here it is:

I suggest making it big, if not full screen, and make sure you have the volume up for the first few seconds.

The coyotes really set the mood, didn’t they? Even though I was freezing my toes and fingers off, it was truly a wonderful and fun evening. I’ve seen a dozen or more total lunar eclipses, and I think my favorite part of this one was sharing my photos on Twitter in near real time. People all over the world were excited to see it, and that is a big part of why I do this.

Due to the complex and subtle dance of gravity and geometry, there will be three more total lunar eclipses visible to the United States over the next year and half: in October this year, and in April and September of 2015. While there won’t be any bright stars near the Moon for the eclipse in October, the planet Uranus will be only a degree away! That’ll make for some nice family portraits. And there’s also a partial solar eclipse two weeks later, on Oct. 23, 2014, too! That’ll be a treat. And if you live in Australia there’s a nice annular solar eclipse on April 29; this is when the Moon is slightly smaller than the Sun and leaves a ring of Sun around the dark Moon. There was one of these last year and there were some fantastic pictures and video. I hope we’ll get more.

Remember: Look up! There are always amazing things to see.

Cassini May Have Witnessed the Birth of a New Saturn Moon!

Tue, 04/15/2014 - 04:30

Just when I think Saturn can’t surprise me any more: The Cassini spacecraft may have taken the birth pictures of a new moon! It may have also spotted its demise. Or maybe part of its demise. Also, it may be twins.

OK, let me explain.

The potential moon (nicknamed Peggy) is tiny, probably only about a kilometer (0.6 miles) across—really a moonlet—and is invisible in the Cassini pictures. However, its presence is betrayed by an odd clumping of material at the very edge of Saturn’s A ring, the outermost of Saturn’s main rings.

It was discovered by accident in an image taken on April 15, 2013—one year ago today. The picture above shows the main rings, the thin F ring outside them, and the irregularly shaped moon Prometheus (the actual target of the shot) in the center just inside the F ring. If you look carefully you can see a blob on the edge of the A ring. Here’s a close-up, with the clump indicated:

That’s clearly not a discrete object; it’s about 10 kilometers (6 miles) wide and 1,200 kilometers (740 miles) long, but this is what you would expect if a small object were located near the edge of the ring—and why astronomers think there's most likely a moonlet there. It would have feeble gravity, but enough to affect the ice particles in the ring, creating the long, trailing clump.

Once they knew it was there, the astronomers were able to calculate an orbit for it, and then go back and look for it in older Cassini images. They found the clump in more than 100 such pictures! But in most cases it’s so faint and difficult to see that it was completely overlooked before. It appears brighter at certain viewing angles, which is why it was so obvious in the discovery image. The earliest it was seen was in May 2012, but before then Cassini was not in a good orbit to detect the clump, so there’s no way to really know how old it is.

But then things get weirder. In images taken before January 2013 there’s only a single object, but in later images, just around the time the object was discovered, a second one appeared! They’re obviously related, but it’s not clear whether the main object broke up due to a collision with something else, or whether Saturn’s tides (the change in the force of gravity over distance) pulled it apart. It may also be due to some other mechanism entirely.

I dug up another of the images showing the clumps, taken on June 22, 2013:

I’ve indicated their locations; you can just see a gap between them and the main A ring. Once I knew what to look for they were obvious, but I can see why they could’ve been missed before. They’re hard to spot. I’ll note that in other images they found what may be a third object as well, but it’s difficult to know what its relationship is to the other two (if any).

And we’re still not done. Not long after the discovery image, Object 2 disappeared! Due to complex interactions with the ring particles, an object the size of the small moon can migrate outward, away from Saturn, over time. Once it leaves the rings it would become essentially invisible. An alternate explanation is that it disintegrated; if its orbit was a bit eccentric, a bit stretched, compared to the particles in the rings it would have been continually bombarded by them, and could have been obliterated.

Still, it was there, at least for a while. And the other object may have survived as well.

So I suppose congratulations are in order for Saturn on its possible new moon … but it’s funny. Saturn is the Roman name for the Greek god Cronus (or Cronos), who was known for eating all his children to prevent them from overthrowing him (when you get down to it, a lot of the ancient myths are really, really horrid). But now we find out the opposite is true! The smaller moons may have been birthed by Saturn (or at least, its rings) and moved out before they could get eaten.

Science! I’ll take it over myth any day.

Science Ranch 2014: A Few Spots Left

Mon, 04/14/2014 - 11:28

There are only a few spaces left at Science Ranch 2014, a weeklong science-based vacation with me, June 22-28, at the Waunita Hot Springs Ranch in the Rocky Mountains near Gunnison, Colo. In addition to your humble host, we’ll have a geologist and an ecologist with us all week as well. There’ll be science talks, stargazing, nature hikes, horseback riding, rafting, great food, and special programs just for kids. We’ll also be taking a day to visit the staggeringly dramatic Black Canyon, which seriously has to be seen to be believed (check out this photo, for example).

My wife and I both love science, and when we go on vacation we always want to learn more about the natural history of where we travel … that’s why we started Science Getaways. We bring along professional scientists to tell us about what we’re seeing and to answer your questions, and I bring my 8” Celestron telescope so we can view the heavens. The dark skies at Wuanita should provide fantastic views (weather permitting, but summers in Colorado are almost always quite lovely and clear). You’ll have a great time, and you’ll learn something, too.

It’s a vacation with your brain.

No, Scientists Have NOT Found Life in a Meteorite. Again.

Mon, 04/14/2014 - 08:09

Hey, look! This again. An article claiming scientists have found microscopic life in a meteorite. I’ve been getting emails from folks (mostly via Facebook) asking whether this is real.

OK, let’s put this in context: For as long as humans have looked at the stars, we’ve wondered if there is life in space. Once science and technology caught up with our imagination we started using radio telescopes to listen for alien signals, we built giant telescopes on space and on the ground to search for other planets, and spent billions of dollars sending missions to Mars to looks for signs that there was once water flowing there, and even just the potential for life.

So if scientists found actual microbes—living bacteria, as claimed in this case—inside a meteorite that fell from space, I think it might make somewhat bigger news than being reported on some random news-like website you saw linked from Facebook.

And I say "news-like" website because the site in question, World News Daily, is satirical. It has articles with headlines like, “Former Pope Warns of Vatican Alien Agenda” and “Arctic Penguins Now Extinct” (think about it…).

And if the site is being serious, then its scholarly levels make the Daily Mail look like the New York Times.

The article itself is a clever mix of reality and outright crackpottery. It mentions real scientists, like Peter Brown, who is in fact a meteoriticist. The meteorite discussed in the article is claimed to come from a fireball that occurred on March 18, 2014 over southern Ontario; a real event (though, to my knowledge, no meteorites from it have yet been found).

The article also mentions Charles Bolden, the NASA administrator. The quote has a, um, key tell in it:

The general director of NASA, Charles F. Bolden, saluted the discovery and praised the canadian university for it’s exceptional contribution to the world’s astrological knowledge.

Emphasis mine. But I hope you see the point (not to mention the two grammatical errors).

Also, on a hunch, I did a reverse image search on Google using the picture of the meteorite shown in the article. It turns out to be one found in Antarctica a few years back. That’s a bit of a walk from Ontario.

So yeah, to be clear: This article is 100 percent bovine excrement, fertilizer, baloney, nonsense, hokum, and fish-wrappery.

Got it?

I can understand it spreading, though, especially on social media. It only takes one person to post about it (either missing the signs it was satire and taking it seriously, or sharing it as a joke) to get things started. People tend not to read past headlines—did you see the NPR April Fools’ Day joke that proved this?—or in general they just skim an article like this. And even if they do a quick check of the facts by, say, looking up the Ontario fireball event or the names of the scientists, they’ll find they’re real (though I suspect the number of people who would go that far is negligible).

Making it worse is that actual scientists have been making similar claims about life in meteorites lately, all of which have been utterly wrong (see Related Posts below for more about them). Those claims were just plain old bad science, but people half-remember them, and so it's no surprise to me that a joke article can wind up getting taken seriously.

Remember folks, put stuff in context! If the news is this big, you would’ve heard about it sooner and in a more reliable venue. And even that doesn’t make it true; you have to do a little work, dig a little deeper, to get to the truth.

Before hitting that button to send something to all your friends, remember: If you care enough to share, you should care enough to beware.

OK, wow, that was an awful aphorism. How about this: Before you share, use a skeptical glare.

Yeah, that’s worse. Whatever. All I ask is that you hesitate a moment before sharing a story like this one so you can think it over. Does it make sense? Is there another place I can look for more info (cough cough)? Is there a chance this is a joke/hoax/fake/wrong?

If you do that, then you’re well on your way to making the world a more real place. And I thank you for it.

Related Posts

No, Diatoms Have Not Been Found in a Meteorite
UPDATE: No, Life Has Still Not Been Found in a Meteorite
Is NASA Hiding Evidence of Life on Mars? I Seriously Doubt It.
Has Life Been Found In a Meteorite?
Follow-Up: Thoughts on the Meteorite Fossils Claim
Are We Aliens?

Watch the SpaceX Launch Live Today at 20:58 UTC

Mon, 04/14/2014 - 04:30

Today (Monday, April 14, 2014), SpaceX is scheduled to launch a modified Falcon 9 rocket on a resupply mission to the International Space Station. The launch is scheduled for 20:58 UTC (4:58 p.m. EDT), and you can watch it live on NASA TV or Ustream (I prefer the latter; there’s less lag in the video stream).

This third mission for SpaceX to the ISS has some interesting stuff going on. I think the most exciting is the Optical Payload for Lasercomm Science, or OPALS. Spacecraft currently communicate with the ground via radio transmissions, the signal encoded with information much the way as how a radio in your car works. OPALS will use an optical light laser for this instead, which is a big leap forward if it works. Lasers take very little power, and the shorter wavelength of optical light means a lot more info can be encoded into the beam. This test will beam a video taken on ISS along with other information down to the ground.

When I was a kid, I read all of science-fiction author Larry Niven's stuff, and his ships communicated using lasers (they played key roles in several stories, too). When I got older I realized how many advantages there were to using lasers instead of radio, and now it's becoming a reality. Score another one for sci-fi.

Two other payloads include a suite of hi-def cameras that will take video of Earth (to test which designs work best in space) and a nifty package (called Veggie) that will allow the astronauts to grow vegetable plants in space using LED lights.

But there’s still another cool thing: SpaceX will be testing the hardware needed to have the first stage of the Falcon 9 rocket land itself for reuse. This is an idea they’ve been testing with their Grasshopper series of test flights, using landing legs stowed on the side of the booster. After the stage separation (and the second stage lofts the Dragon capsule up into space), the booster will execute a burn to slow down, and the legs will deploy during the burn. This will all happen over the Atlantic Ocean, so it’s not an actual full-up landing burn; it’ll be a splashdown! But it’ll test many of the needed systems for an eventual and literal landing. SpaceX says the odds of this being a completely successful test are low, but it’s worth giving it a shot.

Once the Dragon capsule is in orbit it’ll rendezvous with ISS and berth on April 16. If there is a delay in launch, the next possible launch date is April 18. Various hardware issues on the Dragon and ISS have delayed the original scheduled launch, but engineers have decided it’s a go for today.

SpaceFlightNow will have fairly up-to-date messages loading on its site for more information. I’ll be watching and live-tweeting as well, of course. Watching a rocket launch is always fun, so I hope you’ll join in.