Spectacular View of Two Seemingly Colliding Galaxies Captured By Hubble
Hubble has captured this beautiful new view of NGC 3314, two spiral galaxies located in the constellation Hydra, between 117 and 140 million light-years away from Earth. But they are not really colliding. If they were, they would look like this.
It’s an optical effect: NGC 3314A (on the foreground) and NGC 3314B (on the background) are just overlapping, separated “ten times the distance between our Milky Way and neighboring Andromeda galaxy.”
I just like to think they are in love and smooching. [NASA]
Spiral Galaxy - Spiral galaxies are characterized by a distinct flattened spiral disk with a bright center called the nucleus. Our own Milky Way is a spiral galaxy. Spiral galaxies are represented by the letter S and are divided into four subgroups. These are S0, Sa, Sb, and Sc. S0 galaxies have a bright nucleus but have no spiral arms. Sa galaxies have spiral arms that are wound tightly around the nucleus while the arms of Sc galaxies are wound much more loosely.
Barred Spiral Galaxy - A barred spiral galaxy is very similar to a spiral with one important difference. The arms spiral out from a straight bar of stars instead of from the center. About one third of all spiral galaxies are barred spiral in shape. Barred spiral galaxies are represented by the letters SB and are arranges into three subgroups according to the openness of the arms. These subgroups are labeled DBa, SBb, and SBc. SBa galaxies have a short bar of stars extending from the center while SBc galaxies have a long, well-defined bar.
Elliptical Galaxy - Elliptical galaxies vary in shape from completely round to extremely elongated ovals. Unlike spiral galaxies, they have no bright nucleus at their center. Elliptical galaxies are represented by the letter E and are divided into seven subgroups according to their shape. These subgroups are labeled E0 to E7. E0 galaxies nearly circular in shape while E7 galaxies are extremely elongated or stretched out.
Irregular Galaxy - A fourth type of galaxy is known as the irregular galaxy. These galaxies have no discernable shape or structure. Irregular galaxies are divided into two classes, Im and IO. Im class galaxies are the most common and show just a hint of structure. Sometimes the faint remnants of spiral arms can be seen. IO class galaxies are completely chaotic in form. The large and small Magellanic Clouds are examples of Im class irregular galaxies.
All good things must come to an end, though. The shuttle is flying no more, and within the next couple of years, the aging telescope will gradually wink out too. It will be a terrible loss to science, and it kind of makes you wish someone had a spare Hubble secretly stashed away, just waiting to be unpacked and sent into orbit. That’s what would happen in the Hollywood version, anyway.
But it turns out that it is happening in real life too. The National Science Foundation has just revealed the existence of not one but two pristine, Hubble-class space telescopes still in their original wrappings in a warehouse in Rochester, N.Y. The pair was originally built for the National Reconnaissance Office, the agency in charge of spy satellites, to look down at Earth rather than up into space. But the NRO has moved on to bigger and better instruments, and decided to hand the telescopes over. “It just blew me away when I heard about this,” says Princeton astrophysicist David Spergel, a member of the National Academy of Science’s Committee on Astrophysics and Astronomy. “I knew nothing about it.”
The unexpected gift has sent NASA and the astronomical community, both of which have learned to live with smaller budgets and lower expectations in recent years, into a mild state of shock. It’s not clear what they’ll do with this astonishing gift — and indeed, even among the handful of scientists who have been in on the secret, there’s only a general consensus on how they might use just one of the telescopes, never mind both.
But while the free scopes are essentially there for the taking, there are a lot of hurdles to overcome. The cost of adapting cameras and other instruments to the rest of the components, then launching the whole thing and operating it for years won’t be insignificant. “A 50% discount still means you have to come up with the other 50%,” says Spergel. Still, getting the new scope into space should at least be cheaper than it was to launch the Hubble. “Hubble,” he says, “is really a 1960s-era telescope. It’s very heavy and fairly long. This one will be lighter and smaller.” Even with drastic upgrades, Hertz says, it’s plausible that it would cost just $1 billion to adapt and launch the proposed WFIRST — an absurdly low figure for such a powerful machine.
As for the second free telescope, the consensus so far, says Spergel, is that “we wait until sometime in the 2020s to decide what to do with it.” At the moment, the James Webb Space Telescope, the Hubble’s official successor, is eating up the lion’s share of NASA’s science budget, and even at a discount, there’s no way the agency can move ahead with both of the unexpected freebies at once.
I sure hope this doesn’t kill the James Webb Space Telescope.
I’m with shah on this one, I was already getting pretty amped about the JWST. It seems so promising.
I don’t think there’s too much chance of them scrapping Webb, given what they’ve already invested in it and the fact that it is not just a replacement for Hubble, but its successor. Webb operates differently - as an IR telescope, rather than an optical or UV telescope like Hubble (though Hubble does have some IR capability) - and has a much larger mirror than Hubble, so it can see more and farther.
There’s a good summary of the comparison between the two telescopes here: http://www.jwst.nasa.gov/comparison.html
But it’s super cool that they found two secret Hubble telescopes stashed away! What else could the spies be hiding?