Universe Today

April 20, 2008December 24, 2015 by Ian O'Neill

Soyuz Crew Safe After a Violent Re-entry and Landing 400km Off-target

The highly successful Russian Soyuz spacecraft (NASA)

The Russian Soyuz re-entry capsule, carrying the first South Korean astronaut back to Earth, suffered a “ballistic re-entry” on Saturday, putting the capsule 400 km (250 miles) off-target. This is the second time in a row that the return vessel has landed off course; even officials were shocked about this inaccuracy. The astronauts endured forces of up to 10-G as the capsule took a very steep trajectory as it dropped through the atmosphere for three and half hours. Fortunately the three crew members are safe and well. What’s the explanation for the mishap? An unauthorized change to the flight plan and an old naval superstition…

At least the whole crew returned to Earth safely after their violent re-entry, but questions are being asked as to why the capsule landed so far off course and 20 minutes behind schedule.

The Russian TMA-11 craft touched down on the Kazakh steppe at 4:51am Saturday morning after making the long trip through the atmosphere. On board was South Korea’s first astronaut, Yi So-yeon, Russian cosmonaut Yuri Malenchenko and American Peggy Whitson, who broke NASA’s record for time in space. Whitson spent a total of 377 days orbiting the Earth whilst carrying out experiments on the International Space Station. Yi So-yeon spent 11 days on the station after a flawless Soyuz launch (April 8th) and stay in space. However things seemed to go wrong as the trio undocked from the station and headed home.

According to the BBC report, Russian officials blamed the crew for making changes to the flight plan just before re-entry. This change was not communicated to mission control who assumed the original plan was going ahead. The result from this change was a steeper than normal angle on entering the atmosphere (a.k.a. a ballistic re-entry), putting the capsule hundreds of kilometres off course. Rescue helicopters took 25 minutes to arrive to the landing site where the crew waited in temperatures of 6°C (43°F). Other than the off-target location, apparently the touch-down went according to plan.

See the BBC video coverage of this event »

However, not all sources indicate the sole blame falling on a lack of communication between capsule and mission control. In a controversial statement to reporters, Federal Space Agency chief Anatoly Perminov placed some of the blame on an old naval superstition that the female-dominated crew were bad luck and the first female commander (Peggy Whitson) was responsible for the change of plan.

“You know in Russia, there are certain bad omens about this sort of thing, but thank God that everything worked out successfully. Of course in the future, we will work somehow to ensure that the number of women will not surpass [the number of men].” – Anatoly Perminov

Naturally, this kind of statement will have caused a bit of a stir. A reporter pushed for elaboration and Perminov continued, “This isn’t discrimination. I’m just saying that when a majority is female, sometimes certain kinds of unsanctioned behaviour or something else occurs, that’s what I’m talking about.”

It looks like some space agency officials still believe in old naval superstitions, let’s hope it doesn’t influence future female involvement in the Russian space program. If anything, as the whole crew is safe and well, the South Korean and American should be considered the mission’s “lucky charms”.

Update: April 22nd – Read the developments on this story…

Sources: BBC, Yahoo!, Space.com

April 20, 2008December 24, 2015 by Nancy Atkinson

The Debate Continues: Water or Land Landings for Orion

The development of Constellation is continuing, the U.S. program that will replace the shuttle and send astronauts back to the moon. Two unresolved issues have stood out specifically for the Orion crew vehicle: Orion is currently too heavy for the Ares vehicle to launch it from Earth, and the decision on whether Orion will land in water or on land has yet to be determined. Originally, land landings were the preferred choice, but last December, it appeared program managers were leaning towards returning to the water landings seen during the Apollo era. But recently NASASpaceflight.com reported on a possible solution for the weight problem that could potentially provide an improved capacity for landing on land as well.

Needing to save mass on Orion to make it lighter prompted engineers to re-design the airbags that would be part of the vehicle to as a â€œcontingency Land Landing requirement,â€ according to the article on NASASpaceflight.com. The new airbag system uses a smaller number of airbags than the original concept. As a result, the new airbag system is lighter. Engineers believe the new â€œback-upâ€ system could possibly work well enough to be the primary system and allow land landings to be what NASA calls â€œnominal,â€ or the primary, preferred means of landing.

The upside of landing on land is that thereâ€™s a better chance of being able to reuse the command module, as opposed to landing in the ocean. Additionally, thereâ€™s some who believe returning to water landings is a step backwards for human spaceflight.

The airbags in the proposed new design are deployed out of the lower conical backshell on the Orion vehicle. Just before landing , the airbags would inflate and wrap around the low hanging corner of the heat shield. Upon landing, the airbags are vented at a specific pressure so that they collapse at a controlled rate to ease off the energy load of the spacecraft.

Although this new system has yet to undergo detailed analysis, initial results are viewed as promising on the ability to reduce crew loads to an acceptable level.

NASASpaceflight.com reported that another notable challenge for the Orion vehicle relates to maintaining the spacecraftâ€™s orientation to minimize chance of tumbling during descent. A Reaction Control System (RCS) is being developed, which supposedly is preferred by engineers over retro rockets.

NASA did report last week the successful first full-scale rocket motor test for Orion’s launch abort system. This system would separate the crew module from Ares if an emergency occurred during launch.

Original News Source: NASASpaceflight.com

April 19, 2008December 24, 2015 by Fraser Cain

How Big is Apophis?

Question: How Big is Apophis?

Answer: In case you haven’t heard, Asteroid 99942 Apophis is a near Earth asteroid that astronomers think will make a close flyby to the Earth in 2029. When its trajectory was first calculated back in 2004, it had one of the closest visits to Earth astronomers had seen, and had a 2.7% chance of hitting the Earth.

But follow-up observations brought that risk down to 1 in 45,000. Right now, astronomers think that Apophis is essentially no risk to the Earth. In April, 2008 media reported that a 13-year old German student had caught a math mistake made by NASA, and the risk of an Earth strike was actually 1-45. This later turned out to be a hoax.

Because of its close approach to Earth, space advocacy societies, including the Planetary Society think that the Apophis asteroid would make an ideal target for a human mission, and allow engineers to test out strategies for moving asteroids away from dangerous Earth-crossing orbits.

So back to the original question, how big is Apophis? The best estimate puts it at 270 meters (885 feet across), and it has a mass of 2.1 x 10¹⁰ kg. To give you a sense of scale, the Eiffel Tower in Paris is 324 meters tall.

But now you know its mass and size, you’re probably wondering: what would happen to the Earth if it struck? NASA estimated that a strike by Apophis would release the equivalent of 880 megatons of energy. Just as a comparison, the object that carved out Meteor Crater in Arizona probably released 3-10 megatons of energy.

If Apophis struck land, it would flatten thousands of square km of land, killing millions of people if it hit a densely populated area. But it wouldn’t cause the kinds of long term climate destruction that 1 km and larger asteroids can do. If it hit an ocean, it would create devastating tsunamis in all directions.

Here’s an article explaining techniques that might be used to move an asteroid. And here’s NASA’s official page on Apophis.

April 19, 2008December 24, 2015 by Tammy Plotner

Australian Observatory Captures New Nova In Sagittarius

Hold on to your hats… It’s happening again. According to AAVSO Special Notice #105 released on April 19, another possible nova event is now occurring in Sagittarius. Through their quick actions, Macedon Ranges Observatory in Central Victoria, Australia was on top the alert and imaging.

AAVSO Special Notice #105
Possible Nova in Sgr
April 19, 2008

The CBAT Unconfirmed Observations Page listed
a possible nova in Sgr. After a call on VSNET-ALERT,
Ernesto Guido and Giovanni Sostero (Remanzacco
Observatory) used a robotic telescope near Mayhill, NM
to confirm the new object (VSNET-ALERT 10077).
They provide accurate coordinates (using UCAC2) as:
18:05:58.90 -27:13:56.3 J2000
No magnitude is given by Guido and Sostero, but
the original discovery magnitude was 8.4C on 20080418.
No star close to this position is seen in the
USNO-B nor 2MASS catalogs. Kato (VSNET-ALERT 10075)
indicates that this new outbursting object has
a pre-discovery observation by ASAS:
20080416.3048 11.671V (ASAS (Pojmanski, G. 2002, Acta Astron. 52,397)) but was not visible 3 days earlier.

The quick acting staff at MRO immediately went to work imaging the area and comparing their results to the sky survey plates. The results are clear… Yet another new nova has been discovered.

Says Observatory Director Bert Candusio: “This was as exciting as the first Alert exercise done by the MRO only a few days ago. Although MRO tried to get the observation to the AASVO, we decided to supply the images to Universe Today so the general public could get the first glimpses of this exciting new object.”

Once the coordinates were in place, Joe Brimacombe immediately set to work with a 12.5″ Ritchey Chretien Optical Systems telescope and began imaging the target area with a STL 6303 CCD camera. Within 90 minutes the images were processed and the painstaking process of comparison began. By isolating certain star patterns within the area, the nova event was quickly confirmed and revealed in above comparison image (click to enlarge).

In this day and age of strictly professional observations that only belong to a specific community, it’s fantastic to be able to have a group of scientists share with the general public up-to-the minute findings. We applaud their work!

April 19, 2008December 24, 2015 by Nancy Atkinson

The Odds of Intelligent Life in the Universe

Tropical Saturn. Image credit: Columbia University

When it comes to contemplating the state of our universe, the question likely most prevalent on people’s minds is, “Is anyone else like us out there?” The famous Drake Equation, even when worked out with fairly moderate numbers, seemingly suggests the probable amount of intelligent, communicating civilizations could be quite numerous. But a new paper published by a scientist from the University of East Anglia suggests the odds of finding new life on other Earth-like planets are low, given the time it has taken for beings such as humans to evolve combined with the remaining life span of Earth.

Professor Andrew Watson says that structurally complex and intelligent life evolved relatively late on Earth, and in looking at the probability of the difficult and critical evolutionary steps that occurred in relation to the life span of Earth, provides an improved mathematical model for the evolution of intelligent life.

According to Watson, a limit to evolution is the habitability of Earth, and any other Earth-like planets, which will end as the sun brightens. Solar models predict that the brightness of the sun is increasing, while temperature models suggest that because of this the future life span of Earth will be “only” about another billion years, a short time compared to the four billion years since life first appeared on the planet.

“The Earth’s biosphere is now in its old age and this has implications for our understanding of the likelihood of complex life and intelligence arising on any given planet,” said Watson.

Some scientists believe the extreme age of the universe and its vast number of stars suggests that if the Earth is typical, extraterrestrial life should be common. Watson, however, believes the age of the universe is working against the odds.

“At present, Earth is the only example we have of a planet with life,” he said. “If we learned the planet would be habitable for a set period and that we had evolved early in this period, then even with a sample of one, we’d suspect that evolution from simple to complex and intelligent life was quite likely to occur. By contrast, we now believe that we evolved late in the habitable period, and this suggests that our evolution is rather unlikely. In fact, the timing of events is consistent with it being very rare indeed.”

Watson, it seems, takes the Fermi Paradox to heart in his considerations. The Fermi Paradox is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for, or contact with, such civilizations.

Watson suggests the number of evolutionary steps needed to create intelligent life, in the case of humans, is four. These include the emergence of single-celled bacteria, complex cells, specialized cells allowing complex life forms, and intelligent life with an established language.

“Complex life is separated from the simplest life forms by several very unlikely steps and therefore will be much less common. Intelligence is one step further, so it is much less common still,” said Prof Watson.

Watson’s model suggests an upper limit for the probability of each step occurring is 10 per cent or less, so the chances of intelligent life emerging is low — less than 0.01 per cent over four billion years.

Each step is independent of the other and can only take place after the previous steps in the sequence have occurred. They tend to be evenly spaced through Earth’s history and this is consistent with some of the major transitions identified in the evolution of life on Earth.

Here is more about the Drake Equation.

Here is more information about the Fermi Paradox.

Original News Source: University of East Anglia Press Release

April 19, 2008December 24, 2015 by Ian O'Neill

NASA Official Wants a Six Month Stay on Moon

Lunar footprint from the Apollo missions (NASA)

NASA is exploring the possible designs for lunar bases, intended for an extended stay on the Moon. A NASA official from the Advanced Capabilities Division also said on Friday that they may be inspired by a concept based on the technology of the International Space Station (ISS). Very little official indication about the future of NASA’s lunar policy has come to light, so this is interesting news. Although the statement was suitably sketchy, a six-month extended mission to the Moon seems to be most likely. How does this development compare with the lunar settlement designs already proposed?

When Carl Walz, director of NASA’s Advanced Capabilities Division, says “I would anticipate that we would build something similar as what we are building for the ISS, but maybe something different,” I think we can conclude that his department is keeping its options open as far as the future of Moon bases is concerned. But it seems settlement design isn’t very far along either…

Putting uncertainties in lunar base designs to one side, Waltz did confirm that he envisions a long-term, six-month stay over on the Moon, “We need to establish a long, extended presence on the moon, up to six months — same as the time we spend at ISS,” the veteran astronaut told AFP during a forum on the future of NASA at the University of Miami, Florida. The ISS remains mankind’s best experiment into long-term living in space, so its little wonder the station should be used as a model for Moon bases.

The ISS is due for completion in 2010 and houses three scientists for several months at a time. Also, there is enough room for the regular Shuttle crews who arrive to deliver experiments and attach modules. It’s not hard to imagine a future manned lunar base can be used in a similar way, perhaps have a small long-period contingent of scientists, allowing space for short-term visits.

NASA hopes to return to the Moon by 2020 to build a permanent outpost on our planet’s natural satellite. The settlement will need transportation, communication and power systems (see Building a Base on the Moon: Part 4 – Infrastructure and Transportation), allowing lunar astronauts to have the freedom to carry out scientific research on the lunar surface. Many lunar base concepts utilize local materials to fabricate many aspects of a permanent lunar habitat, and continued research by satellites such as the Japanese probe SELENE will aid future colonists prospect for useful minerals and ores.

“We will live at the moon, work at the moon, do sites at the moon and use its resources.” – Walz

It looks as if NASA is working toward a modular settlement design, using the technology that powers the ISS and would be in keeping with “erectable”, or modular designs. Initially, building Moon bases on Earth (or low Earth orbit) and sending them to the lunar surface appears to be the most viable solution. Once a human presence can be established on the Moon, it seems possible that Mars habitats could be fabricated there and sent to the Red Planet. Exciting times.

More about building a manned base on the Moon:

Source: Physorg.com

April 19, 2008December 24, 2015 by Fraser Cain

Why are there Black Holes in the Middle of Galaxies?

Question: Why are Black Holes in the Middle of Galaxies?

Answer: The black holes you’re thinking of are known as supermassive black holes. Stellar mass black holes are created when a star at least 5 times larger than the Suns out of fuel and collapses in on itself forming a black hole. The supermassive black holes, on the other hand, can contain hundreds of millions of times the mass of a star like our Sun.

Astronomers are now fairly certain that these supermassive black holes are at the heart of almost every galaxy in the Universe. Furthermore, the mass of these black holes is somehow tied to the mass of the rest of the galaxy. They grown in tandem with each other.

When large quantities of material falls into the black hole, it chokes up, unable to get consumed all at once. This “accretion disk” begins to heat up and blaze brightly in many different wavelengths, including X-rays. When supermassive black holes are actively feeding, astronomers call these quasars.

So how do these black holes get there in the first place? Astronomers aren’t sure, but it could be that the dark matter halo that surrounds every galaxy serves to focus and concentrate material as the galaxy was first forming. Some of this material became the supermassive black hole, while the rest became the stars of the galaxy. It’s also possible that the black hole formed first, and collected the rest of the galaxy around it.

Astronomers just don’t know.

April 19, 2008December 24, 2015 by Fraser Cain

Why Haven’t Planets Been Detected Around Alpha Centauri?

Toliman — Artist impression of Alpha Centauri

Question: Why aren’t astronomers looking for planets around nearby stars like Alpha Centauri?
Answer: That’s a great question. Since Alpha Centauri is only a little over 4 light-years away, why aren’t astronomers studying it for planets, instead of the more distant stars.

Astronomers have included stars like Alpha Centauri in their search for extrasolar planets, they just haven’t found them yet. That’s because the techniques used to find extra solar planets require very large planets orbiting very close to their parent stars.

The first technique is called the radial velocity method. This is where the gravity of the planet yanks its parent star back and forth. The changes in the star’s velocity are measurable in the light that reaches the Earth.

The second technique looks for transits. This is where the planet passes in front of the parent star, dimming it slightly. By measuring the amount the light dims, astronomers are able to know if there’s a planet there, calculate its size and even determine what’s in its atmosphere.

A third technique detects microlensing events. A closer star focuses the light from a more distant star with its gravity. From Earth, we see a flare in brightness as the two stars line up perfectly. If the closer star has a planet orbiting it, that will change the light curve that astronomers detect, allowing them to calculate the size of the planet.

Most of the planets discovered to date are known as Hot Jupiters. These are planets much larger than Jupiter that orbit within the orbit of Mercury.

A team of astronomers led by Javiera Guedes from the University of California think that an Earth-sized planet should be detectable orbiting Alpha Centauri. They’re working to get a single dedicated telescope to watch the star, and work out if there are planets there. According to their calculations, it should only take about 5 years of intense observations by a dedicated telescope to work out the answer.

April 18, 2008December 19, 2015 by Fraser Cain

Stuart Blasts Star Naming Companies

When I pitched a story idea to Tammy Plotner about how a president of a public observatory deals with those companies that offer to name stars, I was expecting (hoping) for something pretty negative. I think my request was something like, “could you debunk this please”? The article she actually wrote, Name a Star – Real or Ripoff, was much more nuanced, honest and forthright than I was expecting – I’m really glad she took the direction she did, and reminds me why I’m glad Tammy’s writing for Universe Today.

It’s an interesting dilemma. These people are selling something they have no right to sell and have to be dishonest about it. The best companies provide the coordinates to a real star, and the worst…

Anyway, Stuart over at Cumbrian Sky wrote the opinion I was expecting from Tammy. Completely hard line, but a very well defended position. It’s a great read – Star Naming, Fun or Foul.

If any other blogs out there want to chime in on this topic, I’ll be happy to update this page and link to your opinions as well.

April 18, 2008December 24, 2015 by Tammy Plotner

What’s Up – The Weekend SkyWatcher’s Forecast

It’s big. It’s bright. It’s the Moon! Even though the dark skies will be trashed thanks to the influence of this weekend’s Moon, there’s still a lot of astronomy we can practice together. Grab your telescopes or binoculars and let’s head out, because… Here’s what’s up!

Friday, April 18 – Tonight, if you’re looking at the Moon near the southern cusp you’ll spy two outstanding features. The easiest is crater Schickard – a class V mountain-walled plain spanning 227 kilometers. Named for German astronomer Wilhelm Schickard, this beautiful old crater with subtle interior details has another crater caught on its northern wall which is named Lehmann. But, look further south for one of the Moon’s most incredible features – Wargentin. Among the many strange things on the lunar surface, Wargentin is unique. Once upon a time, it was a very normal crater and had been so for hundreds of millions of years, then it happened: either a fissure opened in its interior, or the meteoric impact which formed it caused molten lava to begin to rise. Oddly enough, Wargentin’s walls did not have large enough breaks to allow the lava to escape, and it continued to fill the crater to the rim. Often referred to as “the Cheese,” enjoy Wargentin tonight for its unusual appearanceâ€¦and be sure to note Nasmyth and Phocylides as well.

Saturday, April 19 – Despite the Moon’s overpowering light, you may have noticed brilliant blue-white Spica very near the Moon tonight. Take the time to look at this glorious helium star, which shines 2300 times brighter than the Sun which lights tonight’s Moon. Roughly 275 light-years away, Alpha Virginis is a spectroscopic binary. The secondary star is about half the size of the primary and orbits it about every four days from its position of about 18 million kilometers from center to center… That’s less than one-third the distance at which Mercury orbits the Sun (here are some planet Mercury facts). The two stars can actually graze during an eclipse. Oddly enough, Spica is also a pulsating variable and the very closeness of this pair make for fine viewing – even without a telescope!

While we’re out, have a look at R Hydrae about a fingerwidth east of Gamma – which is itself a little more than fistwidth south of Spica. R Hydrae (RA 13 29 42 Dec -23 16 52) is a beautiful, red, long-term variable first observed by Hevelius in 1662. Located about 325 light-years from us, it’s approaching – but not so very fast. Be sure to look for a visual companion star as well.

Sunday, April 20 – Tonight’s Full Moon is often referred to as the “Pink Moon” of April. As strange as the name may sound, it actually comes from the herb moss pink or wild ground phlox. April is the time of blossoming and the “pink” is one of the earliest widespread flowers of the spring season. As always, it is known by other names as well, such as the Full Sprouting Grass Moon, the Egg Moon, and the coastal tribes referred to it as the Full Fish Moon. Why? Because spring was the season the fish swam upstream to spawn.

While skies are bright, let’s take this opportunity to have a look at Alpha Canis Minoris, now heading west. If you’re unsure of which bright star is, you’ll find it in the center of the diamond shape grouping in the southwest area of the early evening sky in the northern hemisphere. Known to the ancients as Procyon, “The Little Dog Star,” it’s the eighth brightest star in the night sky and the fifth nearest to our solar system. For over 100 years astronomers have known this brilliant star was not alone – it had a companion, and a very unusual one. 15,000 times fainter than the parent star, Procyon B is an example of a white dwarf whose diameter is only about twice that of Earth. But its density exceeds two tons per cubic inch! (Or, a third of a metric ton per cubic centimeter.) While only very large telescopes can resolve this second closest of the white dwarf stars, even the moonlight can’t dim its beauty.