Tag: Arcturus

Go look at Mars!

By Phil Plait | March 26, 2012 11:00 am

These past few days the Moon, Venus, and Jupiter have been showboating in the west right after sunset. They’re so bright they’re mesmerizing, but you’re missing something if you literally don’t turn around. Sitting in the belly of Leo the Lion is the next planet out from the Sun: Mars.

[Click to enaresenate, and also see a way cool animation of Mars rotating.]

That’s the view seen by frequent BABlog contributor Emil Kraaikamp, who takes pretty amazing astrophotos. But even by eye, Mars is dazzling.

It orbits the Sun farther out than Earth does, so we overtake it every couple of years or so. When that happens Mars and Earth are as close together as they can be — think of it like two cars on a racetrack, so when one passes the other they’re in close proximity, and every other time a lot of distance separates them. This just happened a few weeks ago, so Mars looks amazing right now.

In fact, because Mars is close, it’s been the target of many amateur astronomers recently. Wayne Jaeschke was observing it on March 20th from West Chester, Pennsylvania and noticed something odd: a blob or bulge on the edge of the planet!

[Click to see the original; I brightened the image to make the anomaly more obvious. Go to the CloudyNights forum to see lots more pictures and discussion!]

This is almost certainly a high-altitude cloud of some sort; Mars does have an atmosphere and weather. Clouds over the Red Planet are common enough, and can be spotted through small telescopes, though one at this altitude is unusual. They’ve been seen before like this, so it’s not completely unheard of, but that doesn’t make it any less interesting! Wayne also put up an amazing animation where you can see the cloud on the upper right edge of the planet, and you really get a sense of how high up it is. Alan Boyle at Cosmic Log has more.

But you don’t need a telescope to go out and look! I was out the other night, in fact, and saw the bright star Arcturus rising in the east. Mars and Arcturus are both about the same brightness right now, and also both very close to the same color — Arcturus is a bright orange giant star, much like the Sun will be in a few billion years. If you live in the northern hemisphere, go out around 11:00 p.m. and face northeast. You’ll see the Big Dipper easily enough; extend the arc of the handle down and to the right and you’ll see Arcturus like a charcoal ember glowing in the sky (as we astronomers like to tell people, "Follow the arc to Arcturus").

But if you do have a telescope, now’s the time to look. As our planet pulls away from Mars, it’ll look ever smaller through the eyepiece. Not that Mars is all that big; it’s 1/3 the Earth’s diameter and still 100 million km away! But you never know what you might see.

Image credits: Emil Kraaikamp; Wayne Jaeschke; both used with permission.


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CATEGORIZED UNDER: Astronomy, Pretty pictures

And I saw a star rising in… the WEST?

By Phil Plait | September 12, 2010 7:30 am

Over the next few days, the International Space Station is making a series of excellent early evening passes over the western United States. I missed the one Friday night due to clouds, but Saturday (9/11) was perfectly clear.

With my off-the-shelf digital camera set to ISO 400, f/3.5, and using a 15 second exposure, I got a couple of very cool shots. Here it is rising in the northwest over my back yard:

[Click to embiggen. You really should go see the biggest versions of these shots to appreciate them.]

The bright star in the center is the orange giant Arcturus, a star much like the Sun but already in its death throes. The Sun will look like Arcturus in about 6 billion more years… and bear in mind that while it was only about half as bright as the space station when I took that shot, Arcturus was about a trillion times farther away.

Boy howdy.

Here is another one I took a few seconds later, when the ISS was passing just to the south and east of the constellation of Corona Borealis:
Read More

CATEGORIZED UNDER: Astronomy, Cool stuff, Pretty pictures
MORE ABOUT: Arcturus, ISS, Sagittarius

Time spent doing what you love is never wasted

By Phil Plait | June 17, 2010 10:00 am

Recently, I was performing the mundane task of taking out the trash.

I went from room to room, collecting the detritus of the week. I then spent a few minutes scooping out and changing the cat litter, and, sighing, finally tied up the bag and hauled it out to the bins around the side of the house.

As I lugged the hefty bin out to the curb in the darkness, I did what I do, what I always do, when I go outside: I looked up.

I was greeted instantly with an astonishing sight: the reddish, glowing dot of Mars bumped right up against Regulus, the brightest star in Leo. The two were paired less than a degree between each other, low over the western horizon.

It was beautiful. Mars was the slightly brighter of the pair, and even in the mildly light-polluted and sparsely clouded night sky of Boulder I could see the color difference between the planet, some 240 million kilometers away, and the star, 3 million times farther distant yet.

I let my gaze drift a bit over and saw Saturn looming near Leo’s other end. Venus, I knew, was already behind the mountains, but I could see the Big Dipper standing on its bowl to the northwest. Following the arc of the dipper’s handle, I was led to mighty Arcturus, an orange giant nearing the end of its life, and a harbinger of things to come for our own star. Turning, was that Vega I saw dancing in between my neighbor’s tree branches? Why yes, yes it was. Summer’s coming, Vega is telling me.

My trash-hauling chore was forgotten. I suddenly had a flashback, visceral and total, of being a teenager. Standing at the end of my family’s driveway, I watched the sky. Every clear night you’d find me out there. I spent hundreds of hours, thousands, either gazing with my eye to the telescope or simply with my chin tipped up, the Universe unfolded above me. I would always have to pause when a car drove by, and while my absorption with the task didn’t allow it to occur to me then, I now wonder how many of those people saw me and thought to themselves that I was wasting my time.

But as I stand outside my house as an adult, gaping up at the sky, I am familiar there. The stars are my friends… no, that’s hopelessly anthropomorphic and somewhat twee. But they are like slipping your feet into well-worn slippers, like the first bite of a recipe you’ve perfected by countless trial-and-error meals, like holding a book whose spine has been softened through years of reading and re-reading.

I’m comfortable with the sky. I’m at home there. When I stand in my yard and look up, my heart sings and my mind reaches out. My weekly chore was interrupted, delayed, but it didn’t matter.

I don’t know what your own passion is. But I will say this, and you hear me well: no time is wasted spent under the stars. And no time is wasted spent doing what you love.

Picture credit: Il conte di Luna’s Flickr photostream, used under the Creative Commons license.

CATEGORIZED UNDER: Astronomy, Piece of mind
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