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Stars Over X-villeAttention sky-watchers! Tune in to “Stars Over X-ville” on KTHX-FM 100.1 every Tuesday morning at 7:45 a.m. for an update on happenings in northern Nevada’s skies, with Dan Ruby, Planetarium associate director.
Report for April 29, 2008Mysterious Lights in the Sky Last week a strange phenomenon of mysterious lights over the skies of Phoenix was widely reported; eyewitness accounts described four red lights that slowly changed shape and floated away until going out one by one. Unsurprisingly, the UFO turned out to be an ingenious hoax, the result of roadside flares tied to helium balloons. For a light show with truly extraterrestrial origins, we need only look to the pre-dawn sky early next week, as the eta Aquarid meteor shower will be going down. Or, more precisely, the Earth will be plowing through a trail of dust left by Halley’s Comet in one of its historical passes, and those bits of dust will burn up spectacularly as they collide with our relatively thick atmosphere, leaving pencil-thin trails of glowing gas. Last year promised a spectacular shower from this group, but only partially delivered. This year will be much more serene, with rates of maybe a dozen meteors per hour at the peak. However, we luckily have a new moon that night, so there will be no moonshine to interfere. The best time to catch this little show is just before dawn (say, 4 a.m.) on Monday, May 5, though one may also stumble across some shooting stars on the mornings before and after. As always, the best place to be for a meteor shower is someplace dark; the glow from city lights will likely drown out most of them, so head a few minutes into the middle of nowhere if you want to see anything. If you’re already going to be in the middle of nowhere, and awake at oh-dark-hundred, just remember to look up. Report for April 22, 2008Planet Trio Report for April 15, 2008Eye on Mars No, I don’t mean a new rock feature (like the one resembling a face) has been discovered on the red planet; I mean I’ve got my eye on Mars this month, as do thousands of other people worldwide. Not only is the planet easily visible in our evening skies (see chart below), but final adjustments are being made to put the Phoenix Lander on course for a May 25 landing at a newly-picked site near the edge of Mars’ north polar ice cap:
The site, dubbed “Green Valley,” was picked because of its relative lack of rocks; as you can imagine, landing on boulders would make it very tricky for a lander to do its job of digging and poking around the Martian soil. The Phoenix Lander is an exciting mission with a two-part focus. First, it will study water on Mars; and second, it will see if Mars is now, or ever was, possibly habitable for simple life forms (algae, bacteria, etc). It’s important to note that the Phoenix Lander is not looking for life, but just seeing if conditions on Mars are conducive to it. If the answer is yes, then I’m sure more specific critter-finding missions will ensue. This time around, the lander team has much more information about the landing site than any previous Mars mission, thanks to the incredible cameras aboard the Mars Reconnaissance Orbiter, which allow resolution of objects as fine as one meter across. We can now see whether a landing spot is really strewn with boulders, rather than guessing carefully as we did for past Martian surface missions. Although you won’t be able to pick up such detail with your primitive eyeballs, they’re good enough to spot the planet itself tonight. At about 9 p.m. (dark enough to see it clearly), it’ll be up toward the west, about halfway up the sky. It will be about as bright as the brightest stars, but slightly orange.
Actually, the best time to head out might be at 9:26 p.m. on the dot, since we have an exceptionally bright iridium flare tonight. It will be due east, about halfway up the sky. If you want to be really exact, it’s happening at 21:26:45. Oh, and if Mars really isn’t your thing, Saturn is visible just to the right of the half-full (for you optimists) Moon tonight. Report for March 25, 2008Spring has sprung! The first day of spring this year was March 20 (for us northern hemisphere dwellers), as the vernal equinox occurred around 10:58 p.m. on March 19 our time (which was March 20 for most of the rest of the world). This means, for us, the first official full day of spring was March 20. The time and even date of the equinox varies from year to year, because the equinox is actually a location in space; it’s one of the two points in our orbit that the sun crosses the equator, and because of imperfections in both the earth’s orbit and perhaps more importantly, in our calendar system, the time of the equinox can happen within a couple-day period around March 21 each year. The other point in our orbit where the sun crosses the equator happens in fall, and is called the autumnal equinox. This is all due to the earth’s 23.5º tilt — let’s use an illustration here: So besides warmer weather and longer days, what does this mean for skywatchers? We also have some great evening passes of the newly-upgraded International Space Station:
Report for March 18, 2008The International Space Station (ISS) is currently circling the earth with Space Shuttle Endeavour in tow. This is an exciting shuttle mission as the astronauts are installing new components to the station, including a very cool Canadian robot that can traverse the outside of the station for remote repairs and inspections. The shuttle also is bringing back a French astronaut from his one-month stay on the station and replacing him with an American for a three-month stint. The crew includes a Japanese astronaut, making the space station seem truly international at this point. On a related note, I suspect the metric system is heavily used onboard, and I wonder if that’s ever slightly confusing. I know I would need conversion cheat sheets in every pocket, for sure. You can follow along with mission updates, including photos and video, at the NASA Shuttle site. You can also track the shuttle and station pair yourself above the skies of the Truckee Meadows. There are a couple good passes every day through Saturday, but unfortunately they are all early morning; if you get up early, or feel like making a date of watching the extremely bright pair glide overhead, check out www.heavens-above.com for exact times. In other Space Station news, the European Space Agency (ESA) is currently testing their unmanned cargo ship, intended to deliver supplies to the station (which will be especially useful when the shuttle fleet is retired in a couple years). The 20-ton automated transfer vehicle (ATV) is named the Jules Verne in honor of the famous French author and is actually carrying some of his original notes aboard, appropriately enough. The ATV is scheduled to rendezvous with the station later today, meaning the ISS is a busy place to be. Incidentally, we can see this vehicle in our skies as well; this morning it was just a minute-and-a-half ahead of the station, and tomorrow morning it will be visible about eight minutes ahead of the station along the same path.
Report for March 4, 2008Avalanche on Mars
Image credit: NASA/JPL-Caltech/University of Arizona Scientists using the amazing HiRISE camera aboard the Mars Reconnaisance Orbiter took a nifty picture of an avalanche on Mars last week, at the edge of an icecap. Apart from looking cool, this is another bit to pile on a mountain of evidence pointing to water on Mars in some form; in this case, blocks of ice that sublimate to gas, causing ice and dust avalanches. The HiRISE camera is a cool tool, already used for many discoveries on Mars, including possible caves on the Martian surface. Students can suggest targets for the HiRISE camera, as well as help scientists analyze and report on the images. In other Mars news, we’re on target for a May touchdown of NASA’s Phoenix Lander, which will dig for water and organic material at the edge of the north polar icecap. The red planet can be seen easily tonight with the naked eye; just head out after about 7 p.m., look up, and search for an orange dot brighter than most stars.
Image Credit: www.heavens-above.com These are extremely bright and ultra cool, but only really work if you’re directly in the beam of reflected sunlight from the satellite; for the above time, the location used for calculation is the center of Reno, at the corner of the Truckee River and Virginia Street. Your mileage may vary, depending on how far east/west you are. Your best bet, for maximum flare-age, is to plug your exact coordinates into the calculator at Heavens Above, an excellent astronomy resource.
Report for February 26, 2008Last week was a busy week for sky events, so let’s take some time to bask in the relaxing knowledge that not too much is going on this week, and recap: The total lunar eclipse was, itself, eclipsed by a wall of clouds for almost the duration. I caught about a two-minute break at around 6:45, but that was it. I admit that the following picture is entirely Photoshopped, but it still is pretty accurate: The falling U.S. spy satellite was successfully (we think) shot down by a missile from a US warship at 7:26 p.m. Pacific time during the eclipse. Check it out:
This week, we have much more sedate night skies, likely still hidden behind clouds:
The rule of thumb that stars twinkle, planets don’t is usually true, but not always. Stars tend to be very, very far away, and so always appear as points of light. Their apparent size in our sky is small enough that any turbulence and dust in the thick blanket of air between us and space is enough to make stars wiggle, blink, and even change color. Planets in our solar system, on the other hand, appear slightly larger, because although they are physically smaller they are much, much closer. Think a tiny dot of light versus a near-infinitesimal point. In calm, clear air, planets don’t twinkle. It takes a lot more dust and turbulence to make a planet appear to twinkle, but it does happen.
Report for February 19, 2008
Wednesday, February 20 We are in for a semi-rare treat this week, as we are in a great spot to catch a total lunar eclipse. The last one visible to us was just a few months ago — August 28 — but the next one visible from our area won’t be for another couple years, so if you didn’t catch last year’s then this is your chance. This is going to be a better one, too — we’ll get to see the entire period of totality (when the moon is darkest) after the moon rises, where last year it was well underway by the time the moon popped into view. Lunar eclipses happen when the earth passes directly between the sun and the moon, and the moon falls into the earth’s (admittedly large) shadow. The edge of the earth’s shadow is unsurprisingly fuzzy; often the moon only glances the edge of the shadow (the penumbra) in a partial eclipse, instead of passing through the darkest spot (the umbra) in a total eclipse, so the latter instance is more rare. This dark orange color is a result of the sum of all the sunsets and sunrises happening around the world, casting their orange glow onto the surface of the moon. Thanks to some slick astronomy software (Starry Night™, the software we use in our dome theater) we can see what that would look like to an astronaut on the moon:
In other news, the tumbling spy satellite we talked about two weeks ago is now apparently going to be shot down before it can A) do any damage, or B) fall into nosey hands. This could happen as early as Wednesday (they’re waiting until the shuttle lands, at least), so maybe we’ll have a double feature that night of an eclipse and low-orbit fireworks. A similar test (blowing up a satellite with a missile) was conducted successfully by China last year, but it raised much ire in the international community thanks to the creation of a million bits of dangerous space debris for future satellites and astronauts to worry about. I believe the plan this time is to shoot it down in a way that avoids leaving such space junk in orbit, but I still feel like I’ve stepped into the plot of a bad sci-fi movie. UPDATE: The first attempt at shooting down the USA 193 satellite is planned for 03:30 Universal Time on February 21, which translates to 7:30 p.m. our time on February 20, during the lunar eclipse, as the moon is emerging from the darkest part of the earth's shadow! Unfortunately, I doubt we'll be able to see it, as it's happening about 150 miles above the Pacific Ocean, near Hawaii. Report for February 12, 2008Look, up in the sky, it’s a… space shuttle!
The space shuttle Atlantis made it up Thursday without a hitch, so we now have the shuttle orbiting overhead with the International Space Station. The two will be linked together while the new lab module is set up and the astronauts do some minor maintenance, until next week. This means we get some great passes of the ISS/Shuttle pair every evening. When together, these guys are bright — brighter than most stars, and even brighter than the two evening planets right now (Mars and Saturn). The best shot for us is on Friday, between 6:19 and 6:24 p.m., as the pair travels northwest to southeast, hitting a maximum of about 60º above the horizon at about 6:22 p.m. I believe the following fact has been reiterated nearly to death, but just in case: when the shuttle is docked to the station, one can make out the individual shapes of the craft easily with a pair of binoculars. So dust off that old pair, or, if they’re too dusty or nonexistent, come down to the Planetarium to get a new pair for 40 percent off. In the morning, we still have a nice pairing of Venus and Jupiter in the southeast; see last week’s post for more on that. We missed a partial solar eclipse visible only to penguins in the Antarctic last week, but we’re looking forward to next Wednesday’s (February 20) total lunar eclipse, but we’ll save the details for next week’s installment. Report for February 5, 2008Wow, out sick for a week and I come back to a whole laundry list of space happenings. Let’s knock these out. 1) There is a large (but likely relatively harmless) U.S. spy satellite that will crash into Earth in the next few weeks. At first glance this seems scary, so let’s dispel any possible fears about this and look at the facts.
Predicting where and when this will happen is a bit like forecasting the Super Bowl, which is to say very difficult. But it’s important to remember that our little planet is mostly covered in oceans, and that the remaining bits are largely uninhabited. The chances of it hitting anything significant are astronomically low, pardon the pun. I’m not a statistician, but I’d hazard a guess that a shark attack in Nevada is more likely. Yes, the rocket fuel likely onboard is Nasty Stuff (some kind of hydrocarbon ending in –zine), but on par with the Nasty Stuff that is unfortunately pumped into the air and oceans every day. This kind of thing has happened before many times (including the Russian space station MIR’s re-entry over the Pacific in 2001) with no problems. In the meantime, enjoy the view. Like many other satellites, USA 193 is easily visible to the naked eye, and we can see it pass overhead a few times in the next few mornings, with the best upcoming pass on Saturday, February 9 at 6:04 a.m., passing west-northwest (WNW) to south-southeast (SSE), hitting a maximum altitude of 53º in the southwest (SW) at 6:06 a.m. 2) The space shuttle Atlantis has been rescheduled to launch on Thursday, February 7, to take up a new European lab module to the International Space Station (ISS). The folks at NASA are expecting rain, so it may be postponed again, but if not you can always follow along from home/work via the live NASA TV webcast. 3) Venus and Jupiter are still roughly aligned, meaning the two dots appear near each other in our morning skies. While the best day to catch this was last Friday, they still put on a good show in the southeast before sunrise. From here on out, Venus heads back down toward the horizon and Jupiter swings higher, not meeting up again until the evening skies of next winter. This is actually a pretty spectacular sight; I’ve received many calls about it of the “I’m not crazy, but I saw two lights in the sky this morning” variety. Report for January 15, 2008I have high hopes for clear weather this week, but current predictions are not matching what I see out my window; so much for relying on a weather widget. However, if there’s a break, look for Mars (which, incidentally, will not be hit by an asteroid later this month) high in the east after sunset, and bright Venus in the east before sunrise. In the meantime, you can dust off a pair of binoculars to search for either (or both) of the visible comets we’ve got. Though they technically might be visible to the unaided eye from the absolute middle of nowhere, realistically you’ll need a decent pair of binoculars or a telescope to see ‘em.
17P Holmes is still supposedly visible, at about magnitude 4.3, in the constellation Perseus. The best time to look will be as Perseus passes overhead (right near zenith, away from horizon glow) at about 7:30 p.m. or so. 8P Tuttle reaches its highest point (about halftway up the sky) a bit earlier, around 6:45 p.m. or so, in the constellation Cetus (the sea monster). Be warned that neither of these have spectacular tails, so you’ll be looking for dim smudges at best. If you attempt to find these dirty snowballs yourself, good luck. If you need a pair of binoculars, now is a good time to mention that all in-stock binoculars are 40 percent off in the Planetarium gift shop! Report for January 7, 2008Happy New Year! The new year brings us longer days and shorter nights as we head away from the longest night of the year (December 21st — the winter solstice and first official day of winter) and toward the vernal equinox (March 19th — when day and night are equal in length, and the first official day of spring). It also brings us a few other things: Mars is receding, but still very close, very bright, and very orange-red. Look for it in the east after sunset, above and to the left of Orion. If you tilt your head a bit sideways to make Orion “right side up,” then Mars appears to be directly above his head. The possiblility of an asteroid collision looms on the horizon, though thankfully not ours. There’s a small chance (3.6 percent, or about one in 28) that a good-sized rock (165 feet or so across) could slam into Mars sometime late this month, which would give scientitsts an unprecedented look at this sort of cosmic collision with tools such as the Mars Reconnaisance Orbiter. Finally, there may or may not be a visible comet in our skies. Again. I’m not sure myself, since it’s on the edge of being naked-eye viewable, and the weather hasn’t been conducive to checking it out myself in the past couple days, but if you’re interested in seeing comet Tuttle, either for the first time ever or for the first time since last time it was here in 1994, grab a pair of binoculars, wait for a break in the skies, and check here for specifics on where to look Report for December 11, 2007Geminid Meteor Shower So far 2007 hasn’t quite delivered on its meteor shower expectations, but we’ve got one more chance for a decent show before the year is over. The Geminid meteor shower — so named because the meteors appear to radiate from a point in the constellation of Gemini — reaches its peak this Friday, Dec. 14. Although the peak technically happens a bit after sunrise (around 9 a.m.), the shower is steady, strong and reliable enough that we can look forward to a good show between about midnight and sunrise, as the leading edge of the Earth, plowing through the dusty specks of comet remnants, rotates overhead. The moon will have set in the evening, so with clear weather and from a dark location, you should be able to see up to 100 meteors per hour. Even if Thursday night / Friday morning is a bust with cloudy skies, the night after should be pretty good, too. To best catch a meteor shower, it’s important to find a dark location; around western Nevada, my favorite places are near Pyramid Lake. The best time is around 2 a.m., when the radiant (Gemini) is directly overhead, but anytime between midnight and morning should be okay. From wherever you’re starting, venturing out will require bundles of warm clothes, jackets, and Thermoses, and maybe a jaunt to the middle of nowhere, but those adventurous enough to make the effort will be rewarded with plenty of beautiful multicolored shooting stars. Report for December 4, 2007The space shuttle Atlantis is scheduled to launch Thursday, Dec. 6, 2007, to deliver the European Space Agency’s Columbus module. Columbus is based on an earlier Italian module and is packed with racks of laboratory equipment. It will significantly expand the station’s role as an orbiting science lab, and give the crew a bit more breathing space. This means that we’ll have some good passes of both the Shuttle and the ISS in the next week; each is brighter than most stars, and together they are dazzling — with a good pair of binoculars, two distinct linked points of light (the shuttle and station, respectively) and occasionally the shapes of the crafts, can be made out. We have a bright pass of the solo station tonight (Dec. 4) at 5:20 p.m.; it will travel SSW to ENE, reaching a maximum altitude of about 30º above the horizon (about a third of the way up the sky) in the SE. If you miss it, the station comes around again about an hour-and-a-half (its orbital period) later, at 6:55 p.m., and every evening for the next few nights. Check www.heavens-above.com for exact times and locations. After Dec. 9, 2007, the shuttle will be docked to the station for a few days, making for a real treat, so tune in for details next week, as well as details on the year’s best meteor shower, going down on the morning of Friday, Dec. 14. Links: www.nasa.gov/topics/shuttle_station/index.html Report for November 20, 2007According to Yahoo, the skies should be clear this evening and for the remainder of the week, though it will be much colder than it has been the past couple days. The sun sets at about 4:30 p.m. or so, and Jupiter will remain visible in the southwest as the brightest “star” until it sets an hour later. The moon is waxing (becoming fuller) and about half-full this evening, reaching its fullest point on Friday evening. The moon, when visible, washes out dimmer objects but presents a perfect opportunity to check out craters with a small telescope or binoculars. The Leonid meteor shower peaked unimpressively on Sunday, but we may still see some stray shooting stars from that shower early this week from a dark location in the early morning. The Geminids in mid-December (peaking on the morning of Dec. 14) are a much better bet as the best meteor shower of 2007. Bright reddish Mars rises around 7:45 p.m. in the east; as Earth passes Mars on the inside track (in mid-December), it appears brighter and slightly bigger. It is currently brighter than even the brightest star in the sky, Sirius. For those lucky (or unlucky) enough to be up before the sun rises, we have a double treat of bright Venus in the east, with dimmer-but-still-bright Saturn just above. There are no great Iridium Flares or Space Station passes this week, but feel free to check for yourself.
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