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Herschel's First Science Results, Eagle Nebula
davecl writes "Over the next three days, many new science results will come out from Herschel. The first of these, a view deep inside the stellar nursery of the Eagle Nebula, finds a huge amount of activity, revealing new stars and filaments of dust that could not have been detected by previous telescopes. Also open today is OSHI, the online showcase of Herschel images where all the new science images will be found. Herschel news also available on the Herschel Mission Blog."
No. It has unprecedented resolution for far-infared, but definitely not the first IR space telescope. Enough matter to account for dark matter would form huge structures due to gravity (assuming nebulosity), and thus if they are detectable at Herschel frequencies, they would haven been detected.
Problem is, not enough dark nebulae has been detected to accound for dark matter. However, there are a class of dark matter candidates, "Massive Compact Halo Objects", that are made of "normal matter", just harder to detect than most.
Greetings and Salutations....
Well, it depends on how big a telescope you have. Aperture is everything, alas.
However, even the cheapest scope will show good images of the moon and some level of detail of the planets.
Also, you should be able to see how double stars that appear to be a single point of light when we look at them with the naked eye actually consist of several stars in close proximity.
bigger scopes can show the nebulae and other, dimmer items.
Go check out http://www.skyandtelescope.com/ for many observing suggestions, etc.
YAB - http://blog.beemandave.com/
For a small telescope - say 1.5 to 2 inches and 10 to 100x magnification. The double cluster in Perseus - its below Cassiopeia the W thing and looks like two balls of stars, very pretty at low magnification. The Orion nebula - often called the Sword of Orion, its below the three stars of his belt and is a ghostly greenish mist that you need to zoom a bit more in to see. Dont forget to look at the moon, especially when you can see less than the full moon because the mountains and craters along the line of the shadow look really three dimensional, you can crank the magnification up as far as you like on these, bearing in mind that you have to follow the thing across the sky. Take a look at the website of magazines like Sky and Telescope or Astronomy for more info on what to look at and what it is you are seeing. The Orion Nebula for example is the nearest stellar nursery where new stars are being born. If you want to see pictures of the quality that Herschel produces then download the APOD or Astronomy Picture Of the Day application for a new one each day on your desk top - or go staight to the APOD website which google will find for you.
Facts are history now plebs have politics for religion on social media.
Depends on your skies, more location, how late you are willing to stay until, and of course your scope. For starters, try Pleiads and Orion nebula. If my guess of your position is close enough, you should be able to see both just after the sun sets completely, together with Jupiter. Mars and Saturn should come up much later. If you are feeling adventurous, try Double Cluster, M44 (Beehive), and Andromeda. Those objects I mentioned are typically visible in Binoculars, so should pose no problem for a telescope. The last 3, however, may or may not be naked-eye visible (again, depending on various factors, such like light pollution), and even if they are, might require experienced observers to pick out, so might be hard to find.
Anyone have any recommendations for what I ought to show my 6, 4, and 3 year old
Yes. Show them this post in about 15 years. Think back about how much wonderment you expected them to have when you unwrapped that expensive laundry rack and took them outside in the bitter cold to fight with each other over control of the eyepiece only to have it break off in the 3 year old's greasy hands. Then regale them with the story of how you tried to fix it right there in the snow while they shivered and whined and tried to go back inside the house but you wouldn't let them because, dammit, there is so much cool stuff to see and just wait a damned minute while you put that goddamn eyepiece back on the.. Oh fuck, now you've cut yourself on the plastic shards of the broken socket. And everyone can laugh as you all remember together the Christmas daddy spent in the hospital getting stitches and treatment for frostbite.
Oh, and here's a tip:
Saturn is worth staying up for.
Real Daleks don't climb stairs - they level the building.
Without the use of a telescope you could show your kids the surface of the sun by creating your own pinhole box.
Get as large a rectangular box as you can manage which has its ends as large as possible. Affix a large piece of white paper on the inside of one end, close the box then tape all the seams so light can't enter. Take a pin and punch a hole in the end opposite of the one you put the paper on.
Finally, cut a hole in the side of the box near the end where the paper is. When you look into this hole, you should be looking at an angle down towards the white sheet of paper. Start with a smaller hole and keep making larger until you have the size you need.
Finally, point the end with the pinhole towards the sun then look in the hole in the side of the box. When you align the box correctly, you should see an image of the sun projected onto the white sheet of paper which is perfectly safe for your kids to look at. If you're really lucky, you might see a sunspot or two.
Keep this box so when there is a solar eclipse viewable in your area, your kids can have a great view without having to stare at the sun with funky glasses on.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
The actual numbers that go to make up these images are needed to do any science with them - only a fool would try to do science with a JPEG image, but this does happen. The 'scientific rights' refer to the use of the raw numbers for these images in scientific papers. These rights apply for about 1 year after the observations are taken so that the team that has spent years building the instrument and sorting out its science can benefit. This data then becomes completely public.
Please do not suggest looking at the Sun through a telescope even as a joke, it will blind you. You can buy special filters to put over the end of a telescope at the opposite end to the one you look through, which can make a telescope safe to use. But you had better know what you are doing because even a pin hole in the filter will let in so much light that you will blind yourself. If you have ever seen someone set fire to something with a magnifying glass then you should be pretty wary of putting anything glass between your eyes and the sun. I have been using a telescope to look at the night skies for years and have not yet got around to looking at the sun with anything more than a pinbox because of the danger, I'll keep my eyes safe thanks :-)
This is not a case of "ooh you had better wear a crash helmet in case you fall off your bike". You only occasionally fall off your bike. If you look at the sun through a telescope or binoculars it will blind you - first time, every time. This is why a pinhole box is so cool because you can see something that is literally dangerous to do any other way.
Facts are history now plebs have politics for religion on social media.
No offense, but we'd probably already know if he were horribly, horribly wrong.
I'm confused by this. Are you saying we already know everything about physics? Please elaborate.
And we already know that if we go a few billion years in the future, the Sun won't be there any more
I'm not saying it is pointless to leave, and I sincerely hope we make it out of our solar system without killing ourselves first. It just saddens me that all those colonies of humanity (or whatever we are at that point) will never be able to communicate with each other on a reasonable time scale. Who cares if there is life out there besides our own if we can never see it, or if we do see it, we wouldn't have anyone like us to tell about it by the time we got back.
E pluribus unum
I wish the web site would show conventional images and contrast that with what Hershel see's. Being a laymen, it's hard to gauge exactly how exciting this type of news is when you don't have a basis to compare with.
If Herschel can can find matter previously unseen with other telescopes, can this be used to avoid the dark matter theory?
Short answer: no.
Long answer: there are multiple dark matter problems on multiple scales. Galactic dark matter, which is the only kind Hershel might be able to see, may be baryonic (made up of the same sorts of elementary particles as everything else we know about.) Even that is doubtful, based on dynamical analysis of galactic collisions, which strongly favour a non-baryonic component even on galactic scales. And the thing about non-baryonic dark matter is that whatever it is, it doesn't interact electro-magnetically, at least not to a significant degree. If it did, it would be scattered off ordinary matter and be detectable and visible and have pretty much the same spacial distribution as ordinary matter, which it observably does not in the case of galactic collisions.
On larger scales, we know with as much certainty as we know anything that dark matter must be non-baryonic, and therefore almost certainly won't be visible. The reason we know it must be non-baryonic is because the ratio of hydrogen to helium in the early universe, which we can calculate quite precisely based on the universe we see today, puts a strict limit on the amount of baryonic matter, and the extra-galactic dark matter exceeds that limit by a factor of ten or more.
Finally, "avoiding the dark matter theory" is a funny way of putting things, as if somehow dark matter was bad and it would be a good thing to avoid it. Dark matter is a perfectly sensible explanation some peculiar phenomena, and although it is not the only one, it has proven consistent with the experimental and observational tests that have been used to investigate it, particularly the galactic collision analysis mentioned above.
Blasphemy is a human right. Blasphemophobia kills.
I always thought "dark" was taken to mean "beyond detection with our current instruments" ... i.e. a handy compensating factor to fix theoretical equations when those equations don't match observation.
That's literally all it means... dark matter is matter we haven't observed directly, yes. But it isn't really a compensating factor to fix a theoretical equation. It's something that the extremely well tested and verified equations of gravity strongly suggests must exist. We've used the exact same theory to find other things we were unable to see directly, like exoplanets, that were then subsequently imaged directly. The exoplanet wasn't a 'fudge', it was an experimental prediction.
But the kink that is thrown in the "dark matter is just matter we haven't seen yet" definition is that given the amount of dark matter that should be out there (and we even know where a lot of it should be), it seems unlikely that we wouldn't have seen it already if it was 'normal' matter, like clouds of hydrogen gas or what-not. Cus we can see those. So that would suggest that it isn't 'normal' as in Baryonic matter, and this is what gets some people in a huff because now it seems like the physicists are just making things up. There is precedent for this kind of matter, namely neutrinos which are quite real but very hard to detect. Dark matter would have to be similar, but more massive, so it is true that it is speculative. Which isn't the same as 'made up'. Plenty of particles have been inferred from theory, then later verified by experiment. Like neutrinos.
The enemies of Democracy are
AstronomyCast doesnt quite hit it with me. Its hosted by two people who do the question and answer routine on a topic each week and I'd rather just hear one of them talk about the subject instead of one of them pretending to know nothing about the subject and asking questions. Its all a matter of taste but I find it a bit too packaged and distracting. Like it was trying to be a conversation but came out awkwardly like a script. The information is always top notch and interesting stuff but the style of the show is not my cup of tea. The Jodcast recently asked its listeners whether they wanted the "objects in the sky for the upcoming month" to be read as a question and answer thing and they voted for one person to talk about it. As I say its a matter of taste so I pointed out a couple of other shows, in case the one I wasn't so keen on, put people off podcasts - theres a big sky out there and there's lots of different podcasts too.
I could mention a few more in addition to
AstronomyCast http://www.astronomycast.com/ top quality show with different subjects explored in depth with a teaching mission that will leave you much better informed than anything on tv ever will. The pedogogic style doesnt suit me but thats just my taste.
"Slacker Astronomy" http://www.slackerastronomy.org/wordpress/ Practising astronomers interviewed and in-depth subjects discussed by enthusiastic experts, they crack abysmal jokes about technical things which might seem a little silly (or incomprehensible) but the unscripted enthusiasm appeals to me.
The "Jodcast" http://www.jodcast.net/ Science staff from Manchester Universities Joderal Bank radio telescope bring us astronomy news, a themed mini drama, the night sky this month, topical discussion and an oft repeated desire for their theme tune to be redone in a heavy metal version. Well connected on Facebook et al, join in the fun.
there are
NASA Blueshift http://astrophysics.gsfc.nasa.gov/outreach/podcast/wordpress/ A bit slick the last time I listened, with soundbite interviews instead of a bit more detail from a single person. Most NASA stuff is a bit "wow look at that" without too much depth so I only come back to it infrequently. However it is probably perfect for the younger listener and they will probably be hooked by its friendliness.
"Astronomy a Go Go" http://astronomy.libsyn.com/ is the best observing podcast on the net bar none with Alice Few. It may prove a little intimidating to newcomers but the website is also the best general resource for amateur astronomers who want to do observing IMHO. Alice is so thorough and easy on the ear that you could easily play this one three or four times to get yourself fully up to speed on what might be worth doing in the coming month with your observing time. Solid gold this one.
Planetary Radio http://www.planetary.org/radio/ from the Planetary Society is great if you are into rockets and the exploration of the solar system as opposed to deep space. Always an interesting listen with news features, an opinion spot from the self styled "Bill Nye the planetary guy" and loads of enthusiasm for exploring.
365 days of astronomy http://365daysofastronomy.org/ has a few days left to run with a choice of 365 short programs from this The year of Astronomy - The ones from this year best heard now by browsing through the programs to find ones on subjects you are interested in, but the good news is that they are set to carry on with their volunteer generated 5 to 10 minute programs in 2010. Head on over and make a program for them yourself!
The Silicon Valley Astronomy Lectures http://www.astroso
Facts are history now plebs have politics for religion on social media.
The new Herschel image shows part of the constellation of Aquila, meaning the Eagle. However, this is not the Eagle Nebula or M16: that is in the constellation of Serpens which is, coincidentally, nearby. To make matters more confusing, perhaps, the two blue parts of the image are star-forming regions, similar in principle to the Eagle Nebula. I believe that the left-hand one is Westerhout 40 and the right-hand one is Sharpless 62.
The reason we have speculated about dark matter is because we can't account for the gravity we observe, isn't it so?
Yes in the same way we couldn't 'account' for the wobble of a star, so we speculated that there were planets around it.
If so, then how come dark matter can interact with non-dark matter via gravity? in other words, if dark matter can distort spacetime like normal matter, then dark matter is normal matter, by all accounts and purposes.
No not exactly, because there are "accounts and purposes" of matter other than having mass. All the "normal" matter around you is Baryonic, and in addition to having spacetime-warping mass, interacts with the strong, weak, and electromagnetic forces.
In contrast, neutrinos only interact with the weak force, and thus can pass through large amounts of normal matter with ease -- it's EM forces that prevent this with normal matter. It also means we can't detect them from a distance, since the weak force is short range and their masses are extremely small. However, if there was a large enough cloud of them (or similar particles), we could infer its existence via the gravitational effect on other masses.
Then why can't we detect it?
Simply put, because all of our direct detection methods involve electromagnetism, so if the dark matter doesn't interact with EM, then it's literally invisible to those methods.
The enemies of Democracy are