There's a lot of excitement surrounding the "Transit of Venus," even though this rare astronomical event will yield little scientific value.

On Tuesday, Venus will cross the face of the sun. The transit will take about seven hours and begin at 6:09 p.m. EDT.

The next time Venus journeys across the sun will be in the year 2117, says Jack Lissauer, Kepler Mission co-investigator and planetary scientist at NASA Ames Research.

"This is the last chance for almost everybody unless we have huge medical advances," Lissauer says.

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"SpaceX's Dragon capsule sits on a barge after being retrieved from the Pacific Ocean after splashdown.

Dragon splashed down in the Pacific Ocean on Thursday, May 31, 2012, at 11:42 a.m. EDT a few hundred miles west of Baja California, Mexico, marking a successful end to the first mission by a commercial company to resupply the International Space Station."

Our Milky Way galaxy is an anomaly in more ways than one. And now, NASA scientists say they know exactly when it will come to an end.

In a universe that is forever spreading apart, the Milky Way has been moving closer to celestial neighbor the Andromeda galaxy. But whether we are in for intergalactic Armageddon or an extraterrestrial fender bender has been a mystery – until now.

“Very interestingly, we find that Andromeda galaxy does appear to be coming straight at us,” said Roeland van der Marel, an astronomer at the Space Telescope Science Institute in Baltimore. He was scheduled to speak at a NASA press conference Thursday.

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Waiting to see a full sun floating on the horizon, New York spectators instead found the urban phenomenon of “Manhattanhenge” a bit underwhelming Wednesday night.

This unique event happens when the sun aligns perfectly with the Manhattan street grid. The sun creates a “radiant glow of light across Manhattan's brick and steel canyons, simultaneously illuminating both the north and south sides of every cross street of the borough's grid,” Hayden Planetarium Director Neil deGrasse Tyson, who named the semi-annual event, said on the planetarium's website.

Georgina Castanon tried to see “Manhattanhenge” on Tuesday, but clouds foiled the photo shoot. But Wednesday night, she and hundreds of other New Yorkers had a little more success.

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The first private capsule to dock at the International Space Station will return to Earth Thursday, nine days after it took off on its historic mission.

The capsule, known as Dragon, was released by the space station's robotic arm at 5:35 a.m. ET. A thruster burn a minute later pushed the spacecraft away from its host, according to SpaceX, the private company that built and operates the Dragon.

On Sunday, Dragon delivered to the space station more than 1,000 pounds of cargo, including food, clothing, computer equipment and supplies for science experiments and has been reloaded with everything from trash to scientific research and experimental samples.

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A mission 20 years in the making is about to culminate with the launch of a one-of-a-kind satellite.

NASA announced today that its NuSTAR telescope could be shot into orbit as early as June 13.

NuSTAR, short for Nuclear Spectroscopic Telescope Array, will be able to create images of high energy X-rays, making it capable of studying cosmic phenomena such as black holes and how exploding stars form the elements that make up our universe. The new telescope will have 10 times the resolution and 100 times the sensitivity of similar telescopes.

NuSTAR will undergo a flight readiness review on June 1, if it passes that it will be strapped to an aircraft for transport to a launch pad on Kwajalein Atoll in the central Pacific Ocean. If everything goes according to plan, Orbital Sciences Corp. will shoot NuSTAR into space aboard one of its Pegasus XL rockets.

We live in the Milky Way galaxy. Earth is located in one of the galaxy's spiral arms, affording those of us who live in darker parts of the world a view of a band of light snaking across the sky. That band of light is the subject of intense study, as astronomers try to answer questions about its origin and development.

Jason S. Kalirai, an assistant astronomer at the Space Telescope Science Institute (STScI) in Baltimore, has developed a new technique for measuring the age of stars in the Milky Way's halo. The halo is the spherical space around the flatter disk of the galaxy, which contains dense clusters of stars called globular clusters and older stars.

Kalirai's technique makes use of newly formed white dwarf stars to determine the age of their parent stars in the halo to within 0.7 billion years. This is much more precise than the two other techniques available to measure stellar ages in the halo, which are accurate to between 1 and 3 billion years, depending on the technique.

So why do we want to know how old stars in the Milky Way's halo are? The more precisely astronomers can determine those stars' ages, the more precisely they can determine the age of the galaxy itself, which in turn informs the theories of our galaxy's formation and evolution.

Read Kalirai's full study at Nature.com.

"President Barack Obama presents former United States Marine Corps pilot, astronaut and United States Senator John Glenn with a Medal of Freedom, Tuesday, May 29, 2012, during a ceremony at the White House in Washington."

On Tuesday and Wednesday, the setting sun will line up with Manhattan’s skyscrapers to create a unique urban phenomenon dubbed “Manhattanhenge.”

Hayden Planetarium Director Neil deGrasse Tyson, who coined the term for the semi-annual event, explains what happens on the planetarium's website:

“The setting sun aligns precisely with the Manhattan street grid, creating a radiant glow of light across Manhattan's brick and steel canyons, simultaneously illuminating both the north and south sides of every cross street of the borough's grid."

A half-sun will appear on the grid at 8:17 p.m. ET. On Wednesday, a full sun will appear on the grid at 8:16 p.m. Arrive a half-hour earlier for optimal viewing.

"For best effect, position yourself as far east in Manhattan as possible. But ensure that when you look west across the avenues you can still see New Jersey," Tyson says. "Clear cross streets include 14th, 23rd, 34th. 42nd, 57th, and several streets adjacent to them. The Empire State building and the Chrysler building render 34th street and 42nd streets especially striking vistas.”

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I was surprised, leading up to this weekend's top grossing movie, "Men in Black 3," that paranormal phenomena such as UFOs, the Roswell Incident and, yes, the mysterious Men in Black themselves  were conspicuously missing from the zeitgeist.

When the popular sci-fi franchise launched 15 years ago, it was all anyone could talk about. The first "MIB," along with "Independence Day," "The X Files" and "Roswell," brought aliens and government cover-ups their biggest pop culture moment in a generation.

While my geeky friends and I were rabid science fiction fans, excited about the proliferation of these movies and television shows, we scoffed at the idea that any of the aliens or UFOs we saw on screen had any basis in reality.

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