Category Archives: Science

Moon Landing Evidence! :)

In class today (Wednesday), I showed some of the lunar landing footage available to we, denizens of the Internet, for FREE!  NASA is a public entity and as such, happily will show us many awesome things and has given us the Apollo Lunar Surface Journal (ALSJ).  Much of the text was written by former astronauts from the missions themselves and many of the best/crowd-favorite clips provide some context.

Whilst meandering the internet last summer looking for great astronaut videos to use in outreach, I came across this great website: Top 10: Videos From the Moon Landings (from How It Works Magazine).  I’d already found some of them in browsing the COPIOUS video clips in the ALSJ but this website really does have some of the very best :)  My favorites almost always involve the Apollo 17 mission it seems (this is a FANTASTIC Wikipedia page – check out the multimedia at the end!!)…  But I suppose that one was the one with the geologist and he seems a bit more jovial than the others sometimes :)

In the end, don’t let anyone tell you we didn’t land on the Moon.  You can find “Bad Astronomer” Dr. Phil Plait’s debunking here along with a page of several links to debunkers (and deniers!).  You can find the Mythbusters episode debunking here (never mind – you have to find that yourself, they keep taking the versions I know down).  You can find an excellent debunking website called clavius.org here.

Slime molds are smart?

During class on Wednesday, I promised that I would post this story that I read on slime molds following the interstate system.  By the way, this is related to astronomy because “astrobiology” is part of astronomy :)

Photographic evidence!

Click to go to Gizmodo story

Slime molds on a US map - they start at the capital city and there is food (oats) at major urban centers - look at how they grow!

The scholarly journal article is from the preprint server called arXivAre motorways rational from a slime mold’s point of view?  They study 14 different countries and find that, in general, yes, they are rational :)  The Gizmodo article (“Slime Mold and Highways Take the Exact Same Paths“) is also a great synopsis.

What I find just awesome about this is that it seems the interstate system grows pretty naturally.  This makes sense because usually, big highways are the result of people (or animals) going from one place to another and finding the best route…  Why break new ground?  I’ve always felt that certain roads, especially in Atlanta, GA, are really just paved-over cowpaths… Only cows can meander so much in order to be lazy :)

Go outside on March 12 and 13!!

Mercury, Venus, and the Moon aligned. Taken from Paranal Observatory in Chile, March 2008 by Yuri Beletsky.

Right when we come back from Spring Break, we will be able to see a planetary conjunction!  You will be able to see Jupiter and Venus be within three degrees of each other and that’s an especially close separation and will be especially brilliant due to the biology of your eyeball – they will be so close that the “hi-def” part of your eye (the fovea) will be activated.  Here is a NASA article about it: Cold and Spellbinding: An Alignment of Planets in the Sunset Sky

Note that this conjunction is just the kind of thing that early astronomers were trying to predict using the Geocentric (Ptolemaic) model of the Solar System (with all of the epicycles and such).  To be honest, the geocentric model worked pretty well at the beginning, but errors combined over the centuries.  This conjunction is also the kind of thing that astronomers used the Heliocentric model of Copernicus to predict but was just as inaccurate due to Copernicus’ need for perfect circles.  Kepler’s models helped take care of the prediction problems thus the heliocentric model became the accepted model of the Solar System :)

To see how the conjunction works, I’ve put a line on this picture from the NASA/JPL Solar System Simulator.  Note that the line from Earth passes by both Venus and Jupiter :)

Solar System on March 12, 2012

Solar System diagram for March 12, 2012 to illustrate the conjunction of Jupiter and Venus. Note that Venus and Jupiter are along the same line-of-sight from Earth.

Buying a star

Last week, I brought the portable planetarium that I run (the Fisk-Vanderbilt NASA Astronomy Roadshow) to a school north of Nashville.  From both the parents and the students, I got questions about buying a star for someone.  I get these questions a lot – from people when I do outreach, from friends for whom I’m “their” astrophysicist, from students…  It is a really nice idea and very sweet, but IT IS NOT WORTH IT.  Should you do buy a star for someone, you are giving your money away to some opportunists.  The star name company will give you a nice certificate, put your name in a database, and take $50 (or more).  However, there are several companies out there, each with their own databases, and they don’t talk to each other.  “Your” star could also be several other people’s star.  Also, the naming is in no way official – no astronomer will ever, EVER call your star by the name you “buy” – astronomers have our own, internationally agreed upon, usually boring numeric names/designations.

More importantly, the sky is free :)  We should keep it that way.

If you would like more information

Planet Retraction??

In the world of exoplanets (and all of science really), one has to be very careful and very sure of what one is publishing.  Researchers were very sure and very excited when they discovered what looked like a planet around the star Fomalhaut.  Totally looked like an open-and-shut case: they took a picture of Fomalhaut with the Hubble Space Telescope in 2004 and then again in 2006 and saw that there was a spot that moved!  This gave us the infamous “Eye of Sauron” picture :)

Fomalhaut and and the "exoplanet" Fomalhaut-b - "Eye of Sauron" picture

Astronomers love this exoplanet because it is one of the VERY FEW (like 7) planets we actually have images of.  All of the other ones are found through somewhat indirect means – transiting and star wobble (we’ll extensively discuss in class).   But for Fomalhaut-b, all subsequent images have been unable to find the spot again :(  Finally, it seems the infrared Spitzer Space Telescope has nailed the coffin shut…  It took a picture and the exoplanet is not there.  The exoplanet SHOULD be very bright in the infrared because it is hot.  But it is not there.

Bad Astronomer Phil Plait gives a great overview of the topic here and at the bottom of the post has a FANTASTIC little slideshow gallery detailing the planets we ACTUALLY have images of (all 7 of them).

These things happen – new information comes along and we have to re-think all stuff before it.  I’ll be interested to see how Wikipedia gets updated with the new information :)  The entries for Fomalhaut, Fomalhaut-b, and exoplanets will all need to modified at least :)

Global Warming Issues :)

It’s unfortunate that these days, “global warming” is such a dirty word; tis a fascinating topic and one we’ll be investigating a bit during our course (in Unit 3 when we talk about the rocky planets).  Despite the fact we’ll be looking at this more later, I HAVE to post about two things that I found yesterday that remind me of global warming issues.

1.  A Bad Astronomy blog post about new research about the cause of the Little Ice Age also linked to some new data put out by NASA stating the Sun cannot be the cause of global warming. This claim that the Sun’s natural increase in temperature over time (increase is true) is the cause of what we are calling “global warming” is one of the big drums that climate change deniers keep beating on.  But it’s simply not true.  We just go to the data (like the folks at NASA did in the above article).  We’ll talk about it more in class.

2.  One of my sisters is a landscape designer and she provided a link to the newly updated “Plant Hardiness” map published by the USDA.  It shows that the hardiness zones (basically what kinds of plants you can put outdoors) are shifting northerly a bit.

 

However, they are careful to put this statement on their website:

“Climate changes are usually based on trends in overall average temperatures recorded over 50-100 years. Because the USDA PHZM represents 30-year averages of what are essentially extreme weather events (the coldest temperature of the year), changes in zones are not reliable evidence of whether there has been global warming.”

There are other factors in the shift, like better data (more coverage, more accurate) available now, but regardless, it seems mighty interesting to me :)

Radiation and Astronauts

from National Geographic - Biggest solar flare in 4 years

So the Sun flares and bubbles and boils – we’ll learn lots more about that later in the semester.  But when the Sun is doing its thing, what is happening to the astronauts?  And how can humans survive a trip to Mars?

A Facebook friend who works at Goddard Space Flight Center shared a photo and a post by a friend of hers who works with astronauts.  The source of the information in the post is actually from an article on NASA’s homepage and you can find it here.

On that page you’ll find graphs and links and a great description of why it’s actually kind of nice for astronauts to be in the “Solar Maximum” :)  How cool is that!  There are other links on that page to the “Phantom Torso” they study and you can find more for yourself.  In class, we’ll talk about some of the issues of human spaceflight during the last few days of class.

Reflecting, while I am an astrophysicist, I don’t want to be an astronaut right now (and actually never really have)…  Kinda odd many might assume…  But the thing is, I really REALLY want to go see stars and how they work and what weirdo ones look like up close!  But I can’t do that yet – we don’t have the technology :(  Until we do, I’ll keep my feet on the ground and watch the awesome data that comes back to us :)