Herschel delivers spectacular first pictures

Paris, France – Herschel has started making test observations with all its instruments, and the first pictures are in.

The initial targets for the space telescope were galaxies, star-forming regions and dying stars. The instruments provided spectacular data on their first attempt, finding water and carbon and revealing dozens of distant galaxies.
The observations show that Herschel’s instruments are working beyond expectations, says the European Space Agency (ESA).
The first focus for Herschel’s Spectral and Photometric Imaging Receiver (SPIRE) was two galaxies, M66 and M74. The galaxies showed up beautifully, providing astronomers with their best images yet at these wavelengths, and revealing other, more distant galaxies in the background.

The pictures below show M66 and M74 at a wavelength of 250 microns, longer than any previous infrared space observatory, but still the shortest SPIRE wavelength.

Herschel’s primary mirror is 3.5m in diameter, nearly four times larger than any previous infrared space telescope. The panel below shows SPIRE images of M74 at three different far infrared wavelengths.


Scientists used Herschel’s Heterodyne Instrument for the Far-Infrared (HIFI) on 22 June to look for warm molecular gas heated by newborn massive stars in the DR21 star-forming region in Cygnus.

HIFI provided excellent data in two different observing modes, returning information on the composition of the region with unprecedented accuracy and resolution. It works by zooming in on specific wavelengths, revealing different spectral lines that represent the fingerprints of atoms and molecules and even the physical conditions of the object observed. This makes it a powerful tool to study the role of gas and dust in the formation of stars and planets and the evolution of galaxies.

Using HIFI, scientists observed ionised carbon, carbon monoxide, and water in DR21.

The first observation with the Photodetector Array Camera and Spectrometer (PACS) instrument was carried out on 23 June.

The target was the dying star known as the Cat’s Eye Nebula. Discovered by William Herschel in 1786, this nebula consists of a complex shell of gas thrown off by a dying star.

With the PACS spectrometer, it’s possible for the first time to take images in spectral lines and see how the wind from the star shapes the nebula in three dimensions.

PACS observed the nebula in two spectral lines from ionised nitrogen and oxygen. For better orientation, the PACS photometer obtained a small map of the Cat’s Eye Nebula in the 70 micron band, revealing the structure of a dust ring with an opening on one side.

Following these images, Herschel is now in the performance verification phase, where the instruments will be further tested and calibrated. This phase will last until the end of November, after which the mission will begin its routine science phase.