Move over, Hubble: Other telescopes scanning the skies
April 2 planetarium show displays 'Greatest Hits' of the universe
If you have any interest in astronomy, you've undoubtedly heard of Hubble, the space telescope carried into orbit by a shuttle back in 1990.
However Hubble's reputation as the grandest telescope of all has some serious competition from other telescopes, says Pat Hanrahan, planetarium director at Mt. Hood Community College.
'The new telescopes have allowed us to peer into nebulae and witness the birth of new stars and interactions of galaxy mergers,' Hanrahan says.
Hubble's not in trouble, but Hanrahan's excitement does bubble when viewing images captured by such telescopes as the European Space Agency's Herschel and NASA's Spitzer, both of which take infrared images.
'Herschel has a bigger mirror than Hubble and is located beyond the orbit of the moon, whereas Hubble is in low Earth orbit,' Hanrahan says. 'You can get more information with a bigger mirror, and it looks at the universe in infrared. Getting as far away from Earth as possible allows it to see very cool, invisible objects and measure the heat they are releasing.'
Meanwhile, Spitzer can outdo Hubble in looking farther into the infrared part of the light spectrum than Hubble can see.
'Herschel has mapped out the areas of interstellar dust around our sky better than anything else that we have had before,' Hanrahan says.
NASA's Spitzer has given us new information about the Milky Way, he adds.
'Spitzer has imaged stars orbiting around the huge black hole in the center of our galaxy and allowed us to estimate the size of the black hole on the order of four million times the mass of our sun,' Hanrahan says.
Hanrahan plans to talk about Hubble and its competitors in his next presentation, 'The Greatest Hits of the Greatest Telescopes,' on Monday, April 2, in the college's Sky Theatre.
Hubble's not only getting a little competition from other giant telescopes in space, it's getting a run for its interstellar money from telescopes here on Earth.
'The Earth-based telescopes have to look through our atmosphere,' he says, noting this can obscure viewing, kind of like doing bird watching from the bottom of a swimming pool. 'But they have adaptive optics that can greatly reduce the turbulent effects of our atmosphere. I want to show that some of these Earth based scopes have some serious competition for Hubble."
In addition to Hubble, Herschel and Spitzer, Hanrahan says he plans to discuss the Keck Telescope in Hawaii, the Gemini scopes in Hawaii and Chile, the Gran Telescopio Canarias in the Canary Islands, the Southern African Large Telescope, or SALT, in Sutherland, South Africa, and the Large Binocular Telescope in Arizona.
Such telescopes have added to the wealth of information Hubble has provided, Hanrahan says, noting for example, Hubble has no spectrometer to measure galactic distance.
'After Hubble finds new galaxies or quasars that are at the edge of our universe, large telescopes like Keck take pictures of the actual spectra of the galaxy so we can get a better estimate for the distance from the Earth to that galaxy,' he says.
Hanrahan also will talk about what we can see in the night sky this time of year.
'The spring sky continues to show Venus, Mars, Jupiter and Saturn, and Jupiter will soon be lost to the sunset before it reappears in the morning sky later this summer,' he says. 'We'll learn where to find these planets in the night sky and see how they are changing their locations.'
If you go
WHAT: 'The Greatest Hits of the Greatest Telescopes'
WHEN: 7 and 8:15 p.m. Monday, April 2
WHERE: Sky Theatre, Mt. Hood Community College, 26000 S.E. Stark St.
COST: $2, free for students with i.d.