Space and astronomy news
Just as sound can echo off distant objects, light can echo too. And the echoes of light bouncing off stellar remnants, black hole accretion disks, and clouds of gas and dust provide astronomers with another method of probing the distant cosmos.
Download Ep. 215: Light Echoes
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Light Echoes shownotes and transcript.
Have you ever wanted to go to space, but lacked the… everything… to be an astronaut? A whole new industry of space tourism will take you where you need to go. There are new companies offering zero-G flights, sub-orbital flights, and there have even been paying customers who have gone into orbit. Is this going to be space travel for the rest of us?
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This week’s Carnival of Space is hosted by Chris Dann over at Weird Warp.
Click here to read the Carnival of Space #186.
And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.
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One of our celestial neighbors, the spiral galaxy NGC 247, just moved about a million light-years closer.
Well, not really. But astronomers are retooling estimates of the distance to it, which was overestimated in the past partly because of the nearly edge-on tilt, shown above. The just-released image, from the Wide Field Imager on the MPG/ESO 2.2-metre telescope in Chile, shows large numbers of the galaxy’s component stars and glowing pink clouds of hydrogen, marking regions of active star formation, in the loose and ragged spiral arms. Numerous other galaxies can be seen in the distance.
NGC 247 (RA 00h 47′ 14″ – 20deg 52′ 04″) is one of the closest spiral galaxies of the southern sky, now believed to lie about 11 million light-years away in the constellation Cetus (The Whale). It’s part of the Sculptor Group, a collection of galaxies associated with the Sculptor Galaxy (NGC 253, shown in previous releases here and here). This is the nearest group of galaxies to our Local Group, which includes the Milky Way.
To measure the distance from the Earth to a nearby galaxy, astronomers have to rely on a type of variable star called a Cepheid to act as a distance marker. Cepheids are very luminous stars, whose brightness varies at regular intervals. The time taken for the star to brighten and fade can be plugged into a simple mathematical relation that gives its intrinsic brightness. When compared with the measured brightness this gives the distance. However, this method isn’t foolproof, as astronomers think this period–luminosity relationship depends on the composition of the Cepheid.
Another problem arises from the fact that some of the light from a Cepheid may be absorbed by dust en route to Earth, making it appear fainter, and therefore further away than it really is. This is a particular problem for NGC 247 with its highly inclined orientation, as the line of sight to the Cepheids passes through the galaxy’s dusty disc.
However, a team of astronomers is currently looking into the factors that influence these celestial distance markers in a study called the Araucaria Project. The team has already reported that NGC 247 is more than a million light-years closer to the Milky Way than was previously thought, bringing its distance down to just over 11 million light-years.
More information about the lead image: It was created from a large number of monochrome exposures taken through blue, yellow/green and red filters taken over many years. In addition, exposures through a filter that isolates the glow from hydrogen gas have also been included and colored red. The total exposure time per filter was 20 hours, 19 hours, 25 minutes and 35 minutes, respectively.
Source: ESO press release. The paper appears here. See also the website for the Araucaria Project.
Jane Houston Jones from JPL provides a video report on the happenings in space this month, and what you can see in the night sky in March: the MESSENGER spacecraft goes into orbit around Mercury on the 18th, and you can see the swift planet in the evening skies, too! Meanwhile, celebrate Sun-Earth day on the 19th, and view the sun through solar safe telescopes.
Jones was also featured on a recent 365 Days of Astronomy podcast, talking with Jane Platt and providing a “Sneak Peek at the Springtime Skies.”
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It may seem illogical, but boiling is a very efficient way to cool engineering components and systems used in the extreme environments of space.
An experiment to gain a basic understanding of this phenomena launched to the International Space Station on space shuttle Discovery Feb. 24. The Nucleate Pool Boiling Experiment, or NPBX, is one of two experiments in the new Boiling eXperiment Facility, or BXF.
Nucleate boiling is bubble growth from a heated surface and the subsequent detachment of the bubble to a cooler surrounding liquid. As a result, these bubbles can efficiently transfer energy from the boiling surface into the surrounding fluid. This investigation provides an understanding of heat transfer and vapor removal processes that happen during nucleate boiling in microgravity. Researchers will glean information to better design and operate space systems that use boiling for efficient heat removal.
Bubbles in microgravity grow to different sizes than on Earth. This experiment will focus on the dynamics of single and multiple bubbles and the associated heat transfer.
NPBX uses a polished aluminum wafer, powered by heaters bonded to its backside, and five fabricated cavities that can be controlled individually. The experiment will study single and/or multiple bubbles generated at these cavities. It will measure the power supplied to each heater group, and cameras will record the bubble dynamics. Analysis of the heater power data and recorded images will allow investigators to determine how bubble dynamics and heat transfer differ in microgravity.
“With boiling, the size and weight of heat exchange equipment used in space systems can be significantly reduced,” said Vijay Dhir, the experiment’s principal investigator at the University of California, Los Angeles. “Boiling and multiphase heat transfer is an enabling technology for space exploration missions including storage and handling of cryogenic, or extremely low temperature liquids, life support systems, power generation and thermal management.”
“The cost of transporting equipment to space depends on the size and weight of the equipment,” added David Chao, the project scientist from NASA’s Glenn Research Center in Cleveland. “The knowledge base that will be developed through the experiment will give us the capability to achieve cooling of various components and systems used in space in an efficient manner and could lead to smaller and lighter spacecraft.”
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For many of us, this is the first break in the weather we’ve seen for quite some time. Of course, when opportunity knocks, you’ve got to be there to open the door… and today John Chumack took the opportunity to point his Baader solar filter film equipped 10″ SCT and Canon Rebel camera the Sun’s way…
If you’ve had the opportunity to follow solar activity, you’ve seen some major sunspots come and go over the last couple of weeks. Now the next bad boy in line is 1164. Just take a look at its progression in this movie from SDO/HMI. Growing sunspot 1164 has a complex “beta-gamma” magnetic field that harbors energy for M-class solar flares. Not just an off chance, either… but a 35% chance over the next two days. But that’s not all that’s going on!
According to Spaceweather.com “A solar wind stream hit Earth’s magnetic field during the early hours of March 1st. The impact sparked a geomagnetic storm that was, at first, minor, but the storm has been intensifying throughout the day. Spotters are now reporting auroras over Northern Ireland, Latvia, Norway, and Sweden. If trends continue, the display could spread to the high latitudes of North America after nightfall. ”
So how do you see aurora? Like John, you’ve got to be there when opportunity knocks! Be outside around nightfall and keep watch loosely to the north. Aurora can appear like distant search lights, reddish clouds or even ghostly green patches of mist. They appear and disappear… Somtimes you can see stars through them and sometimes the aurora is bright enough to block the starlight. Depending on where the auroral oval is at, you can see them to the north, north-east or north-west. There have even been times when the oval has shifted enough that they appear to the south!
Answer the door… it just might be for you!
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The international partners have decided against an historic ‘fly-about’ of the International Space Station, which would have provided one-of-a-kind images of the nearly completed ISS with space shuttle Discovery and an assortment of vehicles from the different participating space agencies docked to the station.
“This morning, our Russian colleagues, after doing their own independent review processes … have determined that they are not in position to recommend doing the fly about, because this particular vehicle is what they consider a new vehicle, the Series 700 vehicle, which is in its maiden flight,” said Kenneth Todd, a manager for Mission Integration and Operations at NASA, speaking at a mission briefing this morning.
The Russians felt they didn’t have the time or opportunity to fully understand, review and work through all the risks of the request of flying the Soyuz around the ISS, an idea which was presented only recently, and after the new Soyuz had already launched to orbit.
“From a MMT perspective, we knew it was critical for all partners to go through their processes,” Todd said. “It wasn’t necessarily what we were hoping to get back, but at the same point I applaud the Russians for doing the right thing, for not disregarding their own processes and making sure they do their own due diligence the way they should. I accepted the recommendation.”
Mission Control in Houston radioed up to ISS commander Scott Kelly and STS-133 Commander Steve Lindsey that the possible Soyuz fly about was a no-go, even though mission managers had already approved an extra day extension of the shuttle mission.
“We’ll now use that extra day for transfer work between the PMM (Permanent Multipurpose Module) and the ISS, to leave the station and crew in the best possible shape when Discovery undocks.” said Capcom Stan Love. “The fly about will not happen during this flight.”
The fly-about –- only proposed about two weeks ago — would have had cosmonauts Alexander Kaleri and Oleg Skripochka along with Kelly to undock from the Russian Poisk module in the Soyuz TMA-01M spacecraft, back away from the ISS so they could show the ISS in its nearly completed configuration, with the shuttle attached, along with the Russian Progress and Soyuz, the European ATV and the Japanese HTV-1.
Todd said the images would not only be historic from an aesthetic perspective, but also provide valuable engineering views and data.
“There are multiple reasons this was going to be a good thing, to do this photo documentation,” he said. “Everytime we do one of these things we learn a lot, and we get a lot of good data about our ability to do this type of function, not just on our side but on the Russian side. I don’t see our review of this as wasted time or effort, and if we ever need to do this in the future, we will have to assess that at the time.”
Todd added that they should be able to get most of the images and data they were hoping for when the shuttle undocks and departs from the ISS next week – save for the historic aspect of having a shuttle docked to the station, along with all the other visiting vehicles.
Earlier today, the crews of STS-133 and the space station successfully installed the Leonardo Permanent Multipurpose Module, essentially storage space (a “float-in” closet – which has also been referred to as a potential Man-cave) which includes supplies. Also tucked inside is Robonaut-2, the first human-like robot to serve on board the space station.
Discovery’s landing is currently set for 11:36 am EST on Tuesday, March 8, 2011.
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How dark are your skies? GLOBE at Night wants to know! Join the 6th annual worldwide GLOBE at Night campaign, which is going on right now in the northern hemisphere. “We are running two campaigns this year, from February 22nd to March 6th and from March 22nd to April 4th in the northern hemisphere and March 24th to April 6th in the southern hemisphere,” said Rob Sparks from the National Optical Astronomy Observatory, which is one of the sponsors for this year’s campaign.
By participating in the international star-hunting campaign, you will help address the problems of light pollution locally as well as globally. More participants are needed this year, so sign up to be a citizen scientist today!
Light pollution is a serious and growing global concern. With half of the world’s population now living in cities, many urban dwellers have never experienced the wonder of pristinely dark skies and perhaps, maybe never will. But light pollution is also a concern in areas of safety, energy conservation, cost, health and effects on wildlife, as well as our ability to view the stars.
But this is also one of the easiest environmental problems you can address on local levels.
GLOBE at Night is a wonderful way for everyone around the world to participate to raise public awareness of the impact of artificial lighting on local environments. This event encourages everyone – students, educators, dark sky advocates and the general public – to measure the darkness of their local skies and contribute their observations online to a world map.
The campaign is easy and fun to do, and as in previous years, there are just five easy steps to participate. But this year, there is now an app for that, where participants can submit their measurements in real time if they have a smart phone or tablet.
“There is now a mobile website to submit data,” Sparks told Universe Today. “It will take the GPS data, time and date from your phone and has a cool little graphic to help you determine the brightness of the sky. It even had a red screen feature for night use.” The app can be found at this link.
To participate, you will match the appearance of the constellation Orion in the first campaign (and Leo or Crux in the second campaign) with simple star maps of progressively fainter stars found. Then you submit your measurements, including the date, time, and location of your comparison. After all the campaign’s observations are submitted, the project’s organizers release a map of light-pollution levels worldwide. Over the last five annual 2-week campaigns, volunteers from more than 100 nations contributed 52,000 measurements, one third of which came from last year’s campaign.
The five easy star-hunting steps are:
1) Find your latitude and longitude.
2) Find Orion by going outside an hour after sunset (about 7-10pm local time).
3) Match your nighttime sky to one of the GLOBE at Night magnitude charts
5) Compare your observation to thousands around the world.
Go to the GLOBE at Night website for all the details. There is even a 10-minute audio podcast on light pollution and GLOBE at Night. Or download a 45-minute powerpoint and accompanying audio. GLOBE at Night is also on Facebook and Twitter.
Be a part of GLOBE at Night and help the campaign exceed the 17,800 observations contributed last year. Your measurements will make a world of difference.
Thanks to the GLOBE at Night team for securing permission for Universe Today to post the lead image, from Wally Pacholka from AstroPics.com and TWAN (The World At Night).
[/caption]NASA’s Space Shuttle Program is inexorably and swiftly headed towards its finale.
With shuttle Discovery orbiting some 200 miles overhead on her final flight, launch preparations for the final flight of Space Shuttle Endeavour moved into high gear.
Endeavour was rolled a few hundred yards from her processing hanger at the Kennedy Space Center to the Vehicle Assembly Building (VAB) where she will be attached to the external fuel tank (ET) and twin solid rocket boosters (SRB) which will power her final trip to space. See photo album below from Alan Walters and Ken Kremer.
NASA plans to transport Endeavour to Launch Pad 39 A on March 9 for the STS-134 missionand her 25th and final flight. Launch is set for April 19.
Endeavour and her six person crew will deliver the Alpha Magnetic Spectrometer, a $1.5 Billion particle physics detector designed to search for dark matter and determine the origin of the Universe. The crew will also deliver a platform that carries spare parts platform parts that will sustain station operations once the shuttles are retired later this year.
The quarter mile trip on a 76 wheeled transporter began about 7 AM this morning (Feb 28). The orbiter was backed tail first out of the processing hanger known as the Orbiter Processing Facility and then ‘rolled over’ to the VAB and parked close to the entrance doors.
Rollover marks the start of the final phase of launch preparations for the STS-134 mission. Hundreds of Shuttle workers who process the orbiters for flight were invited to witness the event and pose for photo ops with the spaceship. Most KSC employees never get the chance to glimpse the orbiters up close.
The next major milestone is for Endeavour to be hoisted and mated to the External Tank on Tuesday and prepare for rollout to the launch pad.
