Universe Today

September 9, 2009December 24, 2015 by Nancy Atkinson

Hubble Wows With New Images

The Butterfly Nebula, as see by the Hubble Space Telescope. Credit: NASA, ESA, and the Hubble SM4 ERO Team

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Hubble is back! The wait is over and here are the new Hubble telescope images from the newly refurbished space telescope. Above is an image taken by the Wide Field Camera 3 (WFC3), a new camera aboard NASA’s Hubble Space Telescope, installed by NASA astronauts in May 2009, during the servicing mission to upgrade and repair the 19-year-old Hubble telescope. This is a planetary nebula, catalogued as NGC 6302, but more popularly called the Bug Nebula or the Butterfly Nebula.

NGC 6302 lies within our Milky Way galaxy, roughly 3,800 light-years away in the constellation Scorpius. The glowing gas is the star’s outer layers, expelled over about 2,200 years. The “butterfly” stretches for more than two light-years, which is about half the distance from the Sun to the nearest star, Alpha Centauri.

And there’s more!

Omega Centauri. Credits: NASA, ESA and the Hubble SM4 ERO Team

This one is absolutely awesome! This zoom into the globular star cluster Omega Centauri converges onto the Hubble Wide Field Camera 3’s panoramic view of 100,000 stars lying in the center of the cluster. The stars vary in age and change color as they get older. Most of them are middle-aged, yellowish stars like our Sun. But as they near the end of their lives, they balloon into red giants, and later still, into hot, blue stars.

Stephan's Quintet. Credit: NASA, ESA, and the Hubble SM4 ERO Team

This portrait of Stephan’s Quintet, also known as Hickson Compact Group 92, was taken by the new Wide Field Camera 3 (WFC3) aboard NASA’s Hubble Space Telescope. Stephan’s Quintet, as the name implies, is a group of five galaxies. The name, however, is a bit of a misnomer. Studies have shown that group member NGC 7320, at upper left, is actually a foreground galaxy about seven times closer to Earth than the rest of the group.

Three of the galaxies have distorted shapes, elongated spiral arms, and long, gaseous tidal tails containing myriad star clusters, proof of their close encounters. These interactions have sparked a frenzy of star birth in the central pair of galaxies. This drama is being played out against a rich backdrop of faraway galaxies.

The image, taken in visible and infrared light, showcases WFC3’s broad wavelength range.

Eta Carinae from Hubble's STIS instrument. Credit: NASA, ESA, and the Hubble SM4 ERO Team

Observations by the newly repaired Space Telescope Imaging Spectrograph (STIS) on Hubble reveals the signature balloon-shaped clouds of gas blown from a pair of massive stars called Eta Carinae. This new observation shows some of the chemical elements that were ejected in the eruption seen in the middle of the 19th century.

STIS analyzed the chemical information along a narrow section of one of the giant lobes of gas. In the resulting spectrum, iron and nitrogen define the outer boundary of the massive wind, a stream of charged particles, from Eta Car A, the primary star. The amount of mass being carried away by the wind is the equivalent one sun every thousand years. While this “mass loss” may not sound very large, in fact it is an enormous rate among stars of all types. A very faint structure, seen in argon, is evidence of an interaction between winds from Eta Car A and those of Eta Car B, the hotter, less massive, secondary star.

Eta Car A is one of the most massive and most visible stars in the sky. Because of the star’s extremely high mass, it is unstable and uses its fuel very quickly, compared to other stars. Such massive stars also have a short lifetime, and we expect that Eta Carinae will explode within a million years.

Hubble Early Release Observation of Barred Spiral NGC 6217. Credit: NASA, ESA, and the Hubble SM4 ERO Team

This image of barred spiral galaxy NGC 6217 is the first image of a celestial object taken with the newly repaired Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope. The camera was restored to operation during the STS-125 servicing mission in May to upgrade Hubble. The barred spiral galaxy NGC 6217 was photographed on June 13 and July 8, 2009, as part of the initial testing and calibration of Hubble’s ACS. The galaxy lies 6 million light-years away in the north circumpolar constellation Ursa Major. The blue haze at the edges are baby stars being born.

About Hubble’s repair, NASA’s Ed Weiler said, “The astronauts basically did a total repair job on Hubble, and fixed two instruments that haven’t been working for a long time. It’s not an 19 year old telescope, it’s a new telescope again.”

NASA admisinatrator Charlie Bolden, who participated in an earlier Hubble repair mission, said at the press conference unveiling the new images that “after almost twenty years of service we are so proud and honored to part of the Hubble story. The telescope is now equipped to last well into the next decade. Hubble is one of the most accomplished scientific instruments ever, and it has captured the imagination of people everywhere.”

For the full gallery of new Hubble images, see this NASA webpage.

And here’s one more: a full view of Jupiter with the impact scar visible.

Jupiter from the newly refurbished Hubble. Credit: NASA, ESA, M. Wong (Space Telescope Science Institute, Baltimore, Md.), H. B. Hammel (Space Science Institute, Boulder, Colo.), and the Jupiter Impact Team

Sources: NASA, ESA

September 9, 2009December 24, 2015 by Nancy Atkinson

Great Views of the ISS and Shuttle From Earth and Space

The ISS and Discovery on Sept. 1, 2009. Credit: Paolo Beltrame

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Paolo Beltrame from Italy sent us this amazing montage of images he took of space shuttle Discovery docked to the ISS on September 1, 2009. See the incredible details visible of the space station and docked shuttle! Paolo is with the Circolo AStrofili Talmassons (Amateur Astronomers Club in Talmassons, or CAST) who have an impressive observatory (take a look at Paolo’s website). He took these selected images from a 2-minute movie taken with a TourcamPro webcam. As impressive as Paolo’s astrophotos are, however, he says his real passion is viewing the night sky with the naked eye. His motto is “Lasciate che i fotoni vengano a me!” (Let the photons come to me!) See a close up of Paolo’s best shot of the ISS/shuttle below, as well as images from other astrophotographers of Tuesday evening’s pass of the shuttle and ISS as they flew in tandem after Discovery undocked from the station on Tuesday afternoon. There’s also video from the shuttle’s flyaround.

The ISS and shuttle on Sept. 1, 2009 at 3:03 UT. Credit: Paolo Beltrame

Below is Kevin Jung’s image of the ISS and shuttle as they flew in tandem over Grand Rapids, Michigan:

Kevin made it home just in time to take this image, and he said the pair of spacecraft went just below Lyra, and you can make out some of the other things in the field, as well. Click the image to see more of Kevin’s handiwork.

And here’s my feeble attempt to image the tandem flyover from my yard in Illinois:

ISS, shuttle and a star. Credit: N. Atkinson

Can anyone guess what the star in the picture might be?

Finally, enjoy some video of the shuttle’s fly-around of the ISS following undocking. This video just shows the the shuttle due to the lack of Ku band downlink availability. Video of the station from the orbiter was not available, but we’ll post it here later if it becomes available.

September 8, 2009December 24, 2015 by Fraser Cain

How Big is Pluto?

Pluto used to be the smallest planet in the Solar System, but now it isn’t a planet any more, thanks to a recent decision from the International Astronomical Union. But now it’s one of the largest dwarf planets, so that’s a good thing. How big is Pluto?

The diameter of Pluto is only 2,390 km across. Just for comparison, that’s about 70% the diameter of the Moon. And it’s a fraction of the size of the Earth; about 18% of the Earth’s diameter.

In terms of volume, Pluto only has 6.39 x 10⁹ km³. That sounds like a huge number, but it’s only 0.59% of the volume of the Earth. In other words, you could put almost 170 objects the size of Pluto inside the Earth.

The mass of Pluto is 1.3 x 10²² kg, which is only 0.2% the mass of the Earth, or 18% the mass of the Moon. Needless to say, Pluto doesn’t have very much mass at all.

The surface area of Pluto is 1.67 x 10⁷ square kilometers. That’s only 3.3% the surface area of Earth, and about the same surface area as Russia.

If you could stand on the surface of Pluto, you would experience only 6.7% the gravity you enjoy on Earth.

We have written many article about Pluto for Universe Today. Here’s an article that explains why Pluto isn’t a planet any more, and here are some interesting facts about Pluto.

Want more information on Pluto? Here’s Hubblesite’s News Releases about Pluto, and here’s a link to NASA’s Solar System Exploration Guide to Pluto.

We’ve recorded an entire episode of Astronomy Cast about Pluto and the rest of the icy outer Solar System. You can find it here.

September 8, 2009December 24, 2015 by Nancy Atkinson

Augustine Commission: Current Funding Won’t Get NASA Out of Low Earth Orbit

In their preliminary report, a panel of independent space experts commissioned by President Obama concluded that any human exploration beyond low-Earth orbit is not viable with the money NASA is expected to receive under the budget for 2010 and beyond. The Augustine Commission proposed several different options for NASA’s future path, which highlighted working closely with other countries and commercial spaceflight companies, as well as extending the life of the space shuttle through 2011. But NASA is on an “unsustainable trajectory,” and going to the Moon or Mars is not possible on the current level of funding, the Commission said. The only way the US could conduct a “meaningful” human spaceflight program would be by adding at least $3 billion annually to NASA’s budget.

See the complete report here (pdf file) but here’s a summary:

“The nation is facing important decisions on the future of human spaceflight,” the Commision Report stated. ” Will we leave the close proximity of low-Earth orbit, where astronauts have circled since 1972, and explore the solar system, charting a path for the eventual expansion of human civilization into space? If so, how will we ensure that our exploration delivers the greatest benefit to the nation? Can we explore with reasonable assurances of human safety? And, can the nation marshal the resources to embark on the mission? Whatever space program is ultimately selected, it must be matched with the resources needed for its execution.”

The Augustine Commision developed five alternatives for the Human Spaceflight Program, including a “Moon First” option or a “Flexible Path.” They said that funding at an increased level of $3 billion additional each year would allow for either plan.

Here’s a graph of the options:

Augustine Commission graph of options for NASA.

Option 1 is to continue with the current funding and the plan of building the Constellation Program. But the shuttle should be kept going until 2011 and then this would mean de-orbiting the ISS in 2016. With the proposed budget, Ares I and Orion are not available until after the ISS has been de-orbited. The heavy-lift vehicle, Ares V, wouldn’t be available until the late 2020s, and worse, funds would be insufficient funds to develop the lunar lander and lunar surface systems until well into the 2030s, if ever.

Option 2 again maintains the current budget. This option extends the ISS to 2020, and it begins a program of lunar exploration using a Lite version of Ares V. The option assumes the shuttles until FY 2011, and it includes a technology development program, a program to develop commercial crew services to low-Earth orbit, and funds for enhanced utilization of ISS. Heavy lift capabilities wouldn’t be developed until late 2020s and going to the Moon is not an option.

The remaining three alternatives employ the budget of an additional $3 billion for FY 2010, which then grows with inflation at a more reasonable 2.4 percent per year.

Option 3 would be keeping the current plan going. De-orbit the ISS in 2016, developing Orion, Ares I and Ares V, and beginning exploration of the Moon. But the shuttle should fly until 2011. The Committee concluded that Ares1/Orion would be available by 2017, with human lunar return in the mid-2020s.

Option 4 would send humans to the go the Moon first. It also extends the ISS to 2020, funds technology advancement, and uses commercial vehicles to carry crew to low-Earth orbit. There are two significantly different variations to this option.

Variant 4A is the Ares Lite variant. This retires the Shuttle in FY 2011 and develops the Ares V (Lite) heavy-lift launcher for lunar exploration. Variant 4B is the Shuttle extension variant. This variant includes the only foreseeable way to eliminate the gap in U.S. human-launch capability: it extends the Shuttle to 2015 at a minimum safe-flight rate. It also takes advantage of synergy with the Shuttle by developing a heavy-lift vehicle that is more directly Shuttle-derived. Both variants of Option 4 permit human lunar return by the mid-2020s.

Option 5. Flexible Path. This option follows the Flexible Path as an exploration strategy. It operates the Shuttle into FY 2011, extends the ISS until 2020, funds technology development and develops commercial crew services to low-Earth orbit. There are three variants within this option; they differ only in the heavy-lift vehicle.

Variant 5A is the Ares Lite variant. It develops the Ares Lite, the most capable of the heavylift vehicles in this option. Variant 5B employs an EELV-heritage commercial heavy-lift launcher and assumes a different (and significantly reduced) role for NASA. It has an advantage of potentially lower operational costs, but requires significant restructuring of NASA. Variant 5C uses a directly Shuttle-derived, heavy-lift vehicle, taking maximum advantage of existing infrastructure, facilities and production capabilities.

All variants of Option 5 begin exploration along the flexible path in the early 2020s, with lunar fly-bys, visits to Lagrange points and near-Earth objects and Mars fly-bys occurring at a rate of about one major event per year, and possible rendezvous with Mars’s moons or human lunar return by the mid to late 2020s.

September 8, 2009December 24, 2015 by Fraser Cain

Destruction of Earth

Planet Killer — Artist's conception of an asteroid hitting Earth.

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Want to destroy the Earth? It’s harder than it sounds. That’s because the Earth is held together by the mutual gravity of 5.97 x 10²⁴ tonnes of rock and metal. In order to blast the Earth apart, you would need to introduce more energy than the gravitational energy holding the whole planet together.

Think about it, if you wanted to bring about the destruction of Earth, you can’t just fly in your orbiting death star and fire a turbo laser at the planet. You might melt a little spot, but it’s not going to cause the planet to detonate like it did in Star Wars. Add up the mutual gravitational attraction of every atom in the Earth, and that’s how much energy you would need coming out of your laser. A laser powerful enough could vaporize the rock and metal and let it escape out into space. Keep that laser firing for billions of years and it should do the trick.

Another possibility would be to strike the Earth with an asteroid large enough to smash the planet. We’ve been hit by millions of asteroids in the past, and one was even thought to have formed the Moon. It would take an object the size of Mars slamming into Earth at more than 11 km/s to actually shatter the planet.

Instead of burning it, or smashing it, you could change the Earth’s orbit into a downward spiral into the Sun. After a few million years the planet would be burned up and destroyed by the Sun. Problem solved. In order to actually shift the Earth’s orbit, you would need to move a heavy asteroid so that it gently nudges the Earth into a spiraling orbit.

Of course, you could just bring an equivalent amount of antimatter, and let the Earth and anti-Earth collide together. The entire Earth would be annihilated in a heartbeat, leaving a flash of energy. Earth destroyed, problem solved.

But in the end, the Earth will likely be destroyed when it’s swallowed up by the Sun in about 7 billion years. When the Sun runs out of fuel, it will expand in size, becoming a red giant star. Astronomers agree it will swallow up Mercury and Venus, but they aren’t sure if it will get so large that it reaches the Earth. But whatever happens, the surface of the Earth will be scorched.

If that doesn’t completely destroy the Earth, you’ll need to wait trillions of years for the planet to get sucked into some black hole. And if that never happens, it might take 10¹⁰⁰ years for the atoms that make up the Earth to decay into pure energy.

Then, the destruction of Earth will be complete.

This is a just a taste of the monumental amount of work it would take to bring about the destruction of Earth. Perhaps the best article every written on the subject is over here at Things of Interest.

You should also read Phil Plait’s book, Death from the Skies, which looks at all the different ways the Universe is trying to kill us.

Want more resources on the Earth? Here’s a link to NASA’s Human Spaceflight page, and here’s NASA’s Visible Earth.

We have also recorded a two-part episode of Astronomy Cast about the End of Everything (including the Earth). Here’s part 1, and here’s part 2.

Reference:
NASA

September 8, 2009December 24, 2015 by Nancy Atkinson

365 Days of Astronomy Podcast Wins Award

365 Days of Astronomy's Parsec Award for Best Infotainment Podcast. Photo courtesy Dr. Pamela Gay

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The 365 Days of Astronomy podcast has been awarded the 2009 Parsec Award for the Best “Infotainment” podcast. The award was presented at the Dragon*Con convention in Atlanta, Georgia on September 5, 2009. The 365 Days of Astronomy podcast was one of 5 finalists for the award, with 50 shows receiving nominations. The novel concept of 365 DoA is to provide podcast for every day of 2009 — the International Year of Astronomy — with the content submitted from people all around the world.

“It has been such a pleasure to work with everyone on this project, from scientists and engineers who work with telescopes and space missions to passionate amateur astronomers and space enthusiasts,” said 365 DoA team member and Universe Today Senior Editor Nancy Atkinson **….

“Everyone who has participated has thrown themselves wholeheartedly into sharing their excitement and knowledge about space and astronomy, creating a collection of podcasts that is likely unequaled anywhere. Those of us who have been fortunate enough to work on this project for the International Year of Astronomy have had the opportunity to ‘meet’ so many wonderful people from all over the world – it has been a great experience!” Atkinson said.

“This show is a testament to what a group of people can accomplish when they follow both their hearts and their heads,” said Pamela Gay, co-chair of the IYA 2009 New Media Task Group. “This project has been a true community effort, with the audio coming from the entire astronomy community from around the world –professionals, amateurs, and people who just love the science. This award literally goes to a cast of hundreds.”

Gay added that although it is just three years old, the Parsec Awards have quickly become one of the most recognizable honors in science and fiction podcasting. “To have our community production receive this award was an amazing experience. This is everyone’s award.” she said.

** This is the first time I’ve ever gotten to quote myself from a press release! What fun! And all of us who have worked with the 365 Days of Astronomy podcast are very excited about the award. Thanks to everyone who has participated by either submitting a podcast or listening! — Nancy

September 8, 2009December 24, 2015 by John Carl Villanueva

VY Canis Majoris

Of all known stars, the VY Canis Majoris is the largest. This red Hypergiant star, found in the constellation Canis Major, is estimated to have a radius at least 1,800 that of the Sun’s. In astronomy-speak we use the term 1,800 solar radii to refer to this particular size. Although not the most luminous among all known stars, it still ranks among the top 50.

Hypergiants are the most massive and luminous of stars. As such, they emit energy at a very fast rate. Thus, hypergiants only last for a few million years. Compare that to the Sun and similar stars that can keep on burning up to 10 billion years.

VY Canis Majoris a.k.a. VY CMa is about 4,900 light years from the Earth. This value, however, is just a rough estimate because it is too far for parallax to be used. Parallax is the most common method for measuring star distances. It is actually a special kind of triangulation method, i.e., similar to the one employed by engineers that make use of angles and a fixed baseline.

Some stars exist in pairs. These are called binary star systems. There are also multiple star systems. VY CMa, however, burns as a single star.

Being a semiregular variable star, VY Canis Majoris exhibits periodic light changes. Its period lasts for about 2,200 days.

The French astronomer Jerome Lalande is credited to be the first person to have recorded VY CMa. The entry in his star catalogue, dated March 7, 1801, lists it as a 7th magnitude star. Apparent magnitude is a unit of measurement for the brightness of a star as observed from Earth. The greater a star’s magnitude, the less bright it is.

Hence, a star with a magnitude of 1 (a.k.a. a 1st magnitude star) is considered among the brightest. There are also negative values, which denote even brighter bodies. Just to give you an idea where VY Canis Majoris stands in terms of brightness, the Sun (the brightest from our perspective) has an apparent magnitude = -26.73, while the faintest objects observable in the visible light spectrum (as detected from the Hubble Telescope) have magnitudes = 30.

It was once believed that VY CMa was a multiple star system. This was due to six discrete components that were measured by observers during the 19th century. Scientists eventually realized that the said discrete components were actually bright areas of the surrounding nebula.

You can read more about the VY Canis Majoris here in Universe Today. Here are the links:

Podcast: Telescopes, the Next Level

Photo of one of the PROMPT Telescopes. Image credit: Aaron LaCluyze

We’ve explained how to get into astronomy and buy your first telescope. Now we’re going to take things to the next level and get you drooling about bigger and better telescopes. If you’re serious about astronomy, what kinds of telescopes will give you the best bang for big bucks?

Click here to download the episode.

Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.

Telescopes, the Next Level show notes and transcript.

September 8, 2009December 21, 2015 by Nancy Atkinson

Podcast: The Constellation Program

It’s been more than 40 years since humans first set foot on the Moon. But plans are in place to return humans to the surface of the Moon, and maybe even to asteroids and the planet Mars. New rockets, landers and flight technology are all under development. Humans are pushing out into space again, and this time we’re going to stay. Let’s take a look at NASA’s new Constellation Program. What’s been developed so far, and what’s coming up.

Click here to download the episode.

Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.

Constellation Program show notes and transcript.

September 7, 2009December 24, 2015 by Nancy Atkinson

Spaceship Sighting Alert!

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If you catch this post on Monday night, you might have a chance to see the International Space Station and Discovery while the space shuttle is still docked to the ISS. Flying as one, the station/shuttle complex is very bright and very easy to spot. But Tuesday evening you’ll be able to see double. The shuttle is scheduled to undock from the station Tuesday at 2:26 pm CDT(19:26 GMT), and if you have clear skies, you should be able to see Discovery slightly trailing the ISS. It will be a great sight — highly recommended!

How do you find out when the duo will be flying over your backyard?

NASA has a Quick and Easy Sightings by City site, where you just search for your country and city which provides local times and the location in the sky where the station will be visible.

The Heaven’s Above website is also an excellent site to find out when the ISS, as well as all sorts of other satellites and other heavenly sights will be visible. At Heaven’s Above, you can plug in your exact latitude and longitude, so if you live in a remote area, you’ll be able to have exact times and locations to look for satellites instead of relying on information for the nearest city.

Spaceweather.com has their Satellite Flyby Tracker page to provide sighting info for the US and Canada. Use this link for other countries around the world.

There’s also this very cool Google Satellite tracker.

Additionally, you can get a notification on Twitter when the space station will be zooming over your skies. Follow Twisst.

Here’s wishing everyone clear skies and great views!