This made my afternoon yesterday, when I was running around like crazy…
This made me sooo happy! And I told Steve, of Tree Lobsters fame, that it made my day. (See how he did it at Mad Art Lab!)
Later that evening, I was totally pooped from my busy day and about to curl up in a ball and sulk, and I get this in a tweet from Steve…
Categories: astronomy · outreach · science
Tagged: art, awesome, cereal, Sagan
If you love music and astronomy, this is the coolest video you will see all day. If you love music and radio astronomy, this is the coolest video you’ll see all month, at least.
The Japanese rock band ACIDMAN released an album called ALMA late last year. The video for the title track is actually set at the Atacama Large Millimeter Array in Chile! This is one of the biggest, baddest telescopes to be hitting the scene, and is a collaboration among astronomers in the US, Europe, and Japan. As a student of radio astronomy since 2003, I’ve seen the project grow up over the years, and it is going to allow astronomers to probe star formation, early galaxies, and exoplanets with exquisite precision.
And this song is so cool…
Categories: astronomy · fun
Tagged: alma, music, nrao, telescope, videos
Why yes, I am quoting Kaylee.
I was going to include this gorgeous image in with a recent Discovery post, but it had nothing to do with the actual story. So, here it is for you to ogle…
Click for hugeness
This ghostly image of the Orion Nebula was taken with the Spitzer Space Telescope in the infrared after the spacecraft had run out of coolant. So, some of the longer wavelength channels no longer work, but the telescope is still allowing astronomers to do amazing science and take breath-taking pictures. This famous nebula is home to nascent stars, dark and dusty clouds, and a whole host of interesting chemical reactions involving the dust and the gas.
Just more of the universe that you can see when you use “invisible light!”
Categories: astronomy · science
Tagged: invisible light, picture, pretty, spitzer
The Carnival of Space is back with edition #182 at Next Big Future after a month-long hiatus. It includes this lovely flyby of Phobos by Mars Express:
And I am back after a week long hiatus during which I was writing LOTS and LOTS for a dissertation year fellowship application. Keep your appendages crossed for me, guys, as I really hope I can get this one. But even if I don’t, at least it got me started on actually writing my thesis. Yippee!
Categories: astronomy
Tagged: carnival, grad school
And no, not the spoiled-teenage-actor type… Instead, it’s this:
WISE, or the Wide-field Infrared Survey Explorer, captured a quickly moving star creating a bow-shock as it plows through interstellar gas and dust. Dust is “warm,” not as hot as stars, and thus can glow in infrared light while being invisible to optical telescopes. The dust in the bow-shock is even warmer than the surrounding material as Zeta Ophiuchi rushes through.
What else glows in infrared light?
Obligatory. (Also, I’m running on little sleep… so, beware.)
So, as an astronomer, I get all kinds of email with people’s pet theories on how the universe works. And it baffles me as to why anyone would think that the “astronomy elite” would be trying to cover up, “the truth” over something that, at the end of the day, doesn’t affect our daily lives. And I try to be as nice and understanding and as optimistic as I can about people in general, but what do you do with this?
The Accretion theory and all its misconceived variations positing, gas and dust gravitationally attracted and became our solar system, are having serious difficulties proving their basic concepts and are flagrantly violating the laws of physics trying to explain the improvable.
Categories: astronomy
Tagged: pseudoscience
So, I’ve begun to make some forays into Astronomy Education Review, a journal about science education specifically as it relates to, of course, astronomy. It has been recommended to me by several people, and I’ve browsed it a bit as I begin to understand the wide-world of assessment.
As a kid, I thought tests were just something you had to get right to move on to the next level. It was a whole lot of rote memory, and much of high school was devoted to teaching to state tests. It is a system that many complain about but few know how to change. After all, as teacher, we really want to know the answer to the immortal question, “Is our children learning?” (Yes, yes, cheap shot.)
So, how do we make learning fun, student-centered, and still get an accurate assessment of learning?
Categories: astronomy · education · outreach
Tagged: assessment, dsbk
Welcome back to the AstroJargon of the whatever-time-frame-I-feel-like series! Here I break down some commonly used terms in astronomy so that the language barrier between scientists and science lovers can be breached. Today I’d like to explain the S-Z Effect, SZE, or Sunyaev-Zel’dovich Effect. I’ve already touched upon this briefly over on Discovery. I wanted to give a bit more of an explanation than just “holes” or “shadows” that is often said in the science media. After all, what does it mean for a galaxy cluster to have a shadow?
Galaxy clusters appear to be exactly what they sound like: groupings of galaxies physically bound together by gravity. They make up the largest bound structures in the universe. There is, however, so much more that they eye cannot see about these guys. Galaxy clusters appear to be dominated by dark matter, which was famously detected in the merging galaxy clusters known collectively as the Bullet Cluster. In fact the baryonic matter that makes up you, me, the planets, the stars, and everything “normal” is just one-fifth of the total mass of a given cluster. As fascinating as dark matter is, however, that doesn’t play into this particular story.
Several galaxy clusters imaged with the Chandra X-Ray Observatory. You can't even see the "insignificant" galaxies!
Categories: astronomy
Tagged: astrojargon, galaxy clusters, scattering, sze
I have written about some interesting highlights from the annual National Radio Sciences Meeting of URSI in Boulder, CO, and would like to finish that off with a topic near and dear to my brain: radio astronomy through the ionosphere.
Low frequency radio astronomy has enjoyed a resurgence in the last few years, partly driven the search for the signal of the epoch of reionization, or EoR. By low frequency, I mean technically around what is called the VHF or “very high frequency” radio band (30MHz – 300MHz). However, most of radio astronomy has centered on the GHz bands, with most recent pushes out to both higher AND lower frequencies to work on new science.
Low frequency radio astronomy is a bit harder than the radio astronomy of the past in part because of the Earth’s ionosphere. This is the ionized part of the atmosphere, meaning that it consists of negatively and positively charged particles. These charged particles can interact with light, aka electromagnetic radiation, and the problem becomes apparent as you move down to tens and hundreds of megahertz. (If you are not used to working with frequencies, just remember that the FM radio band is in this range, and that the wavelength of the light is on the scale of meters! GHz frequencies are measured in centimeters.)
Good for ham radio! Bad for astronomy...
The ionosphere refracts the incoming light, but irregularities and turbulence make it refract differently across a large field of view. In a way, it is analogous to the problem that optical astronomy has had to deal with all along. Stars seem to “twinkle” because of the turbulent troposphere (low, water-bearing layer of the atmosphere.) The latest generations of optical telescopes have been fitted with adaptive and even active optics, where the mirrors are slightly deformed in sync with the changing atmosphere in order to compensate for these effects and get really clear pictures.
The situation is a bit harder for radio astronomy. In order to get the spatial resolution on the sky, as well as the sensitivity needed, we build interferometers, or whole arrays of individual radio telescopes (antennas, elements, stations, etc.) linked together to make one BIG telescope. These interferometers don’t just take an image of the sky, as an optical telescope would, but measure spatial frequencies on the sky. Or, very, very roughly, how much brightness is in big things versus small things. This is then mathematically transformed (imperfectly) into an image. In this way, an interferometer needs to preserve the phase information of light, not just its amplitude, in order to make a proper sky map. And phase is just what the ionosphere likes to mess with.
The worst scenario with a large field of view, widely separated antennas, and all those little fluctuations. From Lonsdale 2005.
So what do we do? Well, as I sometimes say, “one astronomer’s noise is another astronomer’s data.” As we are trying to remove the effects of the ionosphere from our data, there are lots of ionospheric scientists who want to the study the ionosphere itself! So, URSI has been doing a joint-session of ionospheric physics and radio astronomy in the annual US meeting. The astronomers can make measurements of the phase changes in their data and try to interpret them in terms of the ionosphere, whereas the ionospheric people know a lot about how it behaves, and can share data taken with their instruments, such as GPS arrays and ionosondes. They, in turn, can use the telescope data as well to probe new size and time scales. Amazingly, there is still much to know!
In particular, I’m one of those radio astronomers trying to quantify the impact that the ionosphere has on our instrument, PAPER. In order to see the very, very faint EoR signal, we need to make accurate maps and clear out all the foreground “trash” first. I’ve been tracking the short-timescale, small movements of bright sources in the sky as they move through our telescope’s field of view, and determining empirically what ionospheric effects we need to be careful of. Then, I can make a model of our future, large dataset, and apply a realistic ionosphere model to see just how bad the problem will be. (Or not bad… don’t want to be a Debbie Downer!)
The two science communities are just now learning to speak to each other, in terms of jargon and familiarity with each others data. As I learned over dinner and drinks later that evening, we astronomers still have a lot of learn from the ionosphere guys and gals, and there is great opportunity for collaboration! I’m excited for this, as it can only help my push to finish my thesis and get this ionosphere characterized for the ever-important EoR detection to come!
Categories: astronomy · science
Tagged: eor, grad school, ionosphere, paper, travel, ursi
I got a question about this from one of my dearest friends, and so I’ll take a bit of time to answer it here. In the infamous words of Charlie Tolbert at UVa, “Astrology is bunk.”
That’s it. That’s the bottom line. But we’re good skeptics so we’ll delve a little deeper.
(First though, I should note, I just discovered that there is a whole Facebook page called “Astrology is bunk” for students who have had the honor of taking Tolbert’s class. I never did technically, but I was his TA, and enjoyed the class greatly!)
Astrology is essentially the idea that the alignment of the stars and planets when you were born have some kind of effect on your life. But there are some holes in this hypothesis. First of all, only 7 “planets” were known to the ancients: Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn. Astrological forecasting took those into account, but not Uranus and Neptune, which were there, but simply undiscovered. Wouldn’t a good astrologer have realized that something was off, and maybe even predict the existence of those planets long before they were spotted with telescopes. And what about Pluto? It was a planet and now it’s not, how has that ever been worked in?
You think they'd find the gas giants...
Next, there is the question of how the celestial objects affect you. The nuclear forces work over too short of a range, and the electromagnetic force isn’t very useful over large distances as well. Plus, astronomical objects are pretty much neutral anyway. So that leaves us with gravity. I could go through the derivation to show you that the gravitational pull of you mom’s obstetrician is comparable to that of the largest planet of our solar system, Jupiter, but that’s already been done. Note that his or her presence is not included in astrological forecasting. After 4 centuries of study with telescopes, there is nothing special about the planets or stars that would make them seem to affect our lives, and gravity isn’t it.
The topic of the current kerfuffle are the zodiac constellations. Typical Western astrology splits up the human population into 12 “signs” based on the constellation in which the sun was when that person was born. Note that these are specifically the ancient Greek constellations, as if they hold any special knowledge or significance to mysticism. As any good Astro 101 student can tell you, the Earth goes through a process called precession, in which the axis of the Earth slowly moves around a circlethe sky in a 26,000 year cycle. Therefore, celestial north isn’t always at the star Polaris, and was indeed pointed near bright Vega some long time ago. When you map the sun’s position against the background stars, it will change over time! Astronomers have to constantly upgrade their coordinates to keep up, yet Western astrology pays no heed to this, and your newspaper horoscope has the birth range for if you were born thousands of years ago!
July 31 means I'm a Leo! And look, there's the Sun in Leo! Except, I'm not 2000 years old...
The position of the sun on my actual birthday.
Well, apparently an astronomer in Minnesota (eh?) pointed this out to a reporter, and it morphed somehow into this huge DEAL where everyone is trying to recalculate their sign. Or, in some cases, refusing to change because they are so attached to it. It’s okay. I’ve been there. Though I was never really convinced of astrology’s supposed predictive powers, I relished the idea of being lion-like. Grrr. But really, it’s just silliness. The Christian Science Monitor has a really good article about this silliness, and includes the dates and the “13th zodiac sign” Ophiuchus. As they point out, this is not news to anyone who knows their way around the sky.
Finally, one could point out that science has found weirder things than we can dream up in our imaginations. Even if the mechanism seems absolutely implausible, does it work? The data say No. In a review of some 500 studies done on astrology since the 1950s, astrology fails over and over and over again to predict anything about a person. (It is really fascinating and I encourage you to check out the above-linked pdf.) In fact, you could give a whole room of people the same newspaper style horoscope reading and have most of them tell you, “Oh yeah, this sounds like me!” because they are written so generally.
So not only is astrology implausible and incorrect, it just plain doesn’t work. Unfortunately, that’s not the message that came across through the twisted world of the media.
Finally, if astrology does nothing, then what is the harm in belief? Most of the time, nothing. But pseudo-scientific thinking seems to have a way of causing damage in any case, as is cataloged by Tim Farley’s “What’s the Harm” website. Go ahead, check out the astrology section. Sucks, doesn’t it?
A great reference on astrology is on Phil Plait’s original Bad Astronomy website. Also, check out his take on the matter on his blog. Thanks also to Tim Farley’s SkepSearch for weeding out the nonsense.
Shamelessly stolen from the Bad Astronomer...
Categories: astronomy · skeptic
Tagged: astrology, bunk, pseudoscience
I’m a brand new post-doc in astronomy working as part of the CosmoQuest team. My thesis focused on radio astronomy instrumentation. That means, I got to build cool telescopes that will open up new frontiers in the universe. I also love to teach, both in a classroom setting and informally. I'm happy to talk about the universe with anyone who will listen, and I am skeptically curious about all things.
