Friday, April 30, 2010
NGC 7217 is located about 50 million light years distant in the direction of the constellation of Pegasus.
Thursday, April 29, 2010
If you have a few more minutes, check out Tom Lowe's other videos on his Timescapes page on Vimeo. It is wonderful stuff.
Both photos come from the collection of pictures donated by optician Blake Mitchell.
Here is Blake's description for the top photo:
"Bob, Mel & Blake, the living tool-pressing weights."
He gives a more detailed description for the second photo:
"Standing was tiring so we sat down for 30 minutes to press the 68-inch polishing tool into perfect contact with the 200-inch mirror."
From left to right in both pictures is Bob (Robert) George Smith, Melvin Johnson and Blake Mitchell.
Note that the center plug is in place in these photos. The center plug was used during the grinding and polishing work on the mirror and is now on display at Griffith Observatory.
I don't have firm date on the photos, but I believe that they were taken sometime after work on the 200-inch mirror resumed after the conclusion of World War II.
Wednesday, April 28, 2010
Location may be important in real estate, but it's essential for astronomy, especially when the home you're building is for the world's most advanced and powerful telescope, the Thirty Meter Telescope (TMT). But how do you find the best and what makes one site better than another?
This event will be held June 5 at the Palomar Outreach Center. The evening begins at 5 p.m. with a tour of the grounds of the Palomar Observatory. The presentation begins at 7 p.m. Weather permitting, stay after the talk for a brief view of the night sky through some amateur telescopes. This is a free public lecture, but seating is limited. Call (760) 742-2131 or e-mail email@example.com to make reservations.
Tuesday, April 27, 2010
Since they shot the interview with me the price of a Galileoscope has gone up.They are now $30 each (unless you buy a bunch of them) plus shipping, which is still a bargain.
Sunday, April 25, 2010
Saturday, April 24, 2010
Friday, April 23, 2010
A zoom lens brings them nicely into focus as the crew shovels snow off of the dome:
It is hard work, but somebody has got to do it.
Work will continue throughout the day on snow and ice removal in the public areas and on the domes.
Right it is looking like we will be open for the weekend. I will post a confirmation when it is certain one way or the other.
All of that changed in 1994 when a team of astronomers using Palomar's 60-inch telescope (armed with an early form of adaptive optics) captured the first image of one:
The big blob in the image is a dwarf star known as Gliese 229. The smaller blob to the right is Gliese 229B, the first brown dwarf discovered. The discovery was confirmed just over a year later by the Hubble Space Telescope.
Thursday, April 22, 2010
Wednesday, April 21, 2010
Be careful out there. Palomar Mountain is currently under a Winter Weather Advisory. Fog, wind, snow and icy roads are expected though at least Thursday morning. Travel to the San Diego mountains is not recommended at this time. If you are planning a trip to the observatory, it might be a good time to put it off for a while.
No word yet if this will affect our weekend tours. I'll post an update later in the week.
Speaking of our tours, here is a nice review of them.
Monday, April 19, 2010
As you can see in this picture from April 24, 1936 there were a number of large defects in the surface of the glass. It was the optician's job to grind past the surface defects before the process of placing the f/3.3 curve to the surface.
Saturday, April 17, 2010
Astronomy Magazine: Small, Ground-Based Telescope Images Three Exoplanets
The Economist: Extrasolar planets: A trick of the light
Physics World: Astronomers develop new planet-hunting tool
Space.com: New Method Could Photograph Earth-Like Planets
Scientific American: Technological Advances Bring Exoplanets into Clearer View
MSNBC: New method could image Earth-like planets
Universe Today: Could an amateur astronomer snap a picture of an exoplanet? (Hint: no).
For more on the exoplanets orbiting star HR 8799 check out this entry over at Wikipedia or this cool exoplanet ap for your iPhone or iPad.
Friday, April 16, 2010
The images were taken early in the morning of October 9, 2009 as the NASA LCROSS probe was impacting the dark lunar crater known as Cabeus.
One frame in this animated gif shows a view that is not corrected by adaptive optics. The second shows an adaptive-optics corrected image.
Cabeus is dark region in the center, just behind the large bright mountain. The field of view is 71 km (40 arcseconds, with ~200m resolution), recorded at 2.1 microns wavelength.
Thanks to Antonin Bouchez and the Adaptive Optics team at Palomar/Caltech/JPL for the use of the images.
Thursday, April 15, 2010
Traffic wanting to pass through the closed section of the road will be routed up and down Palomar Mountain via South Grade and East Grade Roads causing heavier than normal traffic and possible delays.
Wednesday, April 14, 2010
Yes, the Hale Telescope's primary mirror is indeed 5.1 meters across. So why would anyone chose to make a big telescope smaller?
If you look at the photo below, you can see that the Hale's prime focus cage, which hangs over the center hole in the mirror is held up by relatively thin "spider vanes" that obstruct small portions of the primary mirror.
This is a feature of virtually all reflecting telescopes. The astronomers who imaged the planets orbiting the star HR 8799 used an 1.5-meter unobstructed portion of the mirror.
Check out the cartoon version below to see what I mean:
The yellow circle represents the portion of the mirror that was used. This avoids any diffraction caused as the light goes past the spider vanes. Further, the adaptive optics system, which normally corrects over the full aperture of the mirror was used to correct over just the 1.5 meter aperture--giving a much higher level of corrections for distortions caused by Earth's atmosphere.
So by effectively making the Hale Telescope smaller, the research team lead by Gene Serabyn was able to achieve results that had previously been obtained by 8 and 10-meter class telescopes.
From the JPL Press Release:
Small, Ground-Based Telescope Images Three Exoplanets
April 14, 2010
PASADENA, Calif. -- Astronomers have snapped a picture of three planets orbiting a star beyond our own using a modest-sized telescope on the ground. The surprising feat was accomplished by a team at NASA's Jet Propulsion Laboratory in Pasadena, Calif., using a small portion of the Palomar Observatory's Hale Telescope, north of San Diego.
The planets had been imaged previously by two of the world's biggest ground-based telescopes -- one of the two 10-meter (33-foot) telescopes of W.M. Keck Observatory and the 8.0-meter (26-foot) Gemini North Observatory, both on Mauna Kea in Hawaii. The planets, which orbit the star HR 8799, were among the very first to be directly imaged, a discovery announced in Nov. of 2008.
The new image of the planets, taken in infrared light as before, was captured using just a 1.5-meter-diameter (4.9-foot) portion of the Hale telescope's mirror. The astronomy team took painstaking efforts to push current technology to the point where such a small mirror could be used. They combined two techniques -- adaptive optics and a coronagraph -- to minimize the glare from the star and reveal the dim glow of the much fainter planets.
"Our technique could be used on larger ground-based telescopes to image planets that are much closer to their stars, or it could be used on small space telescopes to find possible Earth-like worlds near bright stars," said Gene Serabyn, an astrophysicist at JPL and visiting associate in physics at the California Institute of Technology in Pasadena. Serabyn is lead author of a report on the findings in the April 15 issue of the journal Nature.
The three planets, called HR8799b, c and d, are thought to be gas giants similar to Jupiter, but more massive. They orbit their host star at roughly 24, 38 and 68 times the distance between our Earth and sun, respectively (our Jupiter resides at about five times the Earth-sun distance). It's possible that rocky worlds like Earth circle closer to the planets' star, but with current technology, they would be impossible to see under the star's glare.
The star HR 8799 is a bit more massive than our sun, and much younger, at about 60 million years, compared to our sun's approximately 4.6 billion years. It is 120 light-years away in the constellation Pegasus. This star's planetary system is still active, with bodies crashing together and kicking up dust, as recently detected by NASA's Spitzer Space Telescope (http://spitzer.caltech.edu/news/1000-feature09-16-Unsettled-Youth-Spitzer-Observes-a-Chaotic-Planetary-System). Like fresh-baked bread out of the oven, the planets are still warm from their formation and emit enough infrared radiation for telescopes to see.
To take a picture of HR 8799's planets, Serabyn and his colleagues first used a method called adaptive optics to reduce the amount of atmospheric blurring, or to take away the "twinkle" of the star. This technique was optimized by using only a small piece of the telescope. Once the twinkle was removed, the light from the star itself was blocked using the team's coronograph, an instrument that selectively masks out the star. A novel "vortex coronagraph," invented by team member Dimitri Mawet of JPL, was used for this step. The final result was an image showing the light of three planets.
"The trick is to suppress the starlight without suppressing the planet light," said Serabyn.
The technique can be used to image the space lying just fractions of a degree from a star (about one degree divided by roughly 10,000). This is as close to the star as that achieved by Gemini and Keck -- telescopes that are about five and seven times larger, respectively.
Keeping telescopes small is critical for space missions. "This is the kind of technology that could let us image other Earths," said Wesley Traub, the chief scientist for NASA's Exoplanet Exploration Program at JPL. "We are on our way toward getting a picture of another pale blue dot in space."
JPL is a partner with the California Institute of Technology in Pasadena in the Palomar Observatory. Caltech manages JPL for NASA. More information about exoplanets and NASA's planet-finding program is at http://planetquest.jpl.nasa.gov . More information about the Palomar Observatory is at http://www.astro.caltech.edu/palomar/ .
Monday, April 12, 2010
The top photo shows a group of people with Edwin Hubble (at right) greeting the 200-inch Pyrex disc as it arrived at Lamanda Park in Pasadena, CA on April 10, 1936.
The photo below, also taken by Ferdnand Ellerman, shows the scene later that day as a crowd gathered to see the 200-inch as it was removed from the rail car.
The next day it was taken by the Belyea Truck Co. to the optical shop at Caltech. Work on the 20-ton glass disc began shortly there after. No one at the time would have imagined that it would remain there for eleven and a half years.
Saturday, April 10, 2010
74 years ago today the train carrying the 200-inch Pyrex disc completed its 16-day trip from Corning, NY to Pasadena, CA. The train pulled in to the station at Lamanda Park and was off loaded later that day.
I'll post a shot of that on Monday for our history photo of the week.
Friday, April 9, 2010
For part of its passage around the Sun this comet offered up a spectacular anti-tail - a spike of dust sometimes seen as a comet passes through the orbital plain of the Earth.
Tuesday, April 6, 2010
On another topic, be sure to click on over to read a story from HPWREN about a Palomar Supernova discovery: Measuring a Monstrous Supernova - On the trail of a strange stellar beast.
Monday, April 5, 2010
The photo was taken October 18, 1937 by Lee A. Farnsworth, Jr, a member of the construction crew on Palomar.
Tonight at 7:30 p.m. I will be giving a talk on the building of the Hale Telescope for the Temecula Valley Astronomers.
Friday, April 2, 2010
This image of edge-on spiral galaxy NGC 4565 was captured by astronomer Milton Humason April 15, 1950. He made a 25 minute exposure from the Hale Telescope's prime focus using red sensitive film.
NGC 4565 is about 20 million light years from our own Milky Way Galaxy in the direction of the constellation Coma Berenices..