Atlas des spectres dans le proche infrarouge de Venus, Mars, Jupiter et Saturne

ICARUS 12 140--144 (1970)

Book Reviews Atlas des Spectres dans le proehe infrarouge de Venus, Mars, Jupiter et Saturne. J. CONNES, P. CONI~ES,a n d J . P. MAILLARD. C e n t r e N a t i o n a l de la R e c h e r c h e Seientifique, Paris, 1969. 473 pp. P r i c e 250 francs. I n t h e s e t i m e s we arc u s e d t o r e g a r d i n g E a r t h b a s e d optical o b s e r v a t i o n s of t h e p l a n e t s as a p a i n f u l l y slow c h i p p i n g - a w a y process in w h i c h slightly more information can be obtained by s l i g h t i m p r o v e m e n t s in i n s t r u m e n t a t i o n a n d l e n g t h of o b s e r v i n g time. T h i s is in s t a r k c o n t r a s t to the spectacular feats of the Mariner and V e n e r a space probes. T h e r e is one e x c e p t i o n t o t h e E a r t h b o u n d d i l e m m a - - t h e r e m a r k a b l e C o n n e s s p e c t r a of t h e p l a n e t s as o b t a i n e d w i t h a F o u r i e r i n t e r f e r e m e t e r w h i c h t o o k y e a r s of p a i n s t a k i n g effort t o c o m p l e t e . T h e s e s p e c t r a c o v e r t h e region o f a b o u t 1.1 t o 2.5/z w i t h r e s o l u t i o n s as h i g h as 0.08 c m -1 for V e n u s a n d Mars, or m a n y orders of m a g n i t u d e better than has been achieved with conventional s p e c t r o m e t e r s . T h e Connes s p e c t r a h a v e r e s u l t e d in several significant r e s u l t s w h i c h h a v e a l r e a d y b e e n p u b l i s h e d : for e x a m p l e , t h e d i s c o v e r y of H F , HC1 a n d CO in t h e V e n u s a t m o s p h e r e and o f CO in t h e M a r t i a n a t m o s p h e r e , a n d a careful a n a l y s i s o f COs lines in b o t h a t m o s p h e r e s . B u t all t h e s e efforts i n v o l v e d t h e p r e s e n t a t i o n of t i n y p o r t i o n s of t h e w e a l t h o f t h e C o n n e s d a t a a n d t h e community-at-large has not yet been exposed to t h e full story. T h i s 473-page a t l a s a n s w e r s t h e n e e d ; it p r e s e n t s t h e v a s t b u l k of t h e C o n n e s s p e c t r a in a neat, e a s y - t o - r e a d f o r m a t , a l o n g w i t h a s h o r t t e x t (in F r e n c h a n d E n g l i s h ) e x p l a i n i n g t h e spect r a . I a m c e r t a i n t h a t t h i s v o l u m e will b e c o m e a n e c e s s i t y for a n y s t u d e n t o f p l a n e t a r y spectroscopy, w h e t h e r h e b e a t h e o r e t i c i a n w h o wishes t o s t u d y several a s p e c t s of t h e s p e c t r a y e t t o b e e x p l o i t e d ( t h e r e are J u p i t e r a n d S a t u r n s p e c t r a i n c l u d e d as well), or a n e x p e r i m e n t e r w h o wishes to design a n i n f r a r e d s p e c t r o m e t e r for a p l a n e t a r y probe. I n s h o r t , t h e i n f o r m a t i o n c o n t e n t in t h i s v o l u m e is e x t r a o r d i n a r y a n d m a y e v e n b e t h e source of several P h . D . theses. T h e w a v e n u m b e r a c c u r a c y is especially impressive. A f t e r a p p r o p r i a t e corrections for D o p p l e r shifts, etc., t h e w a v e n u m b e r a c c u r a c y in t h e Mars a n d V e n u s s p e c t r a is ~ 10 -2 c m - I . T h e r e are a few m i n o r p r o b l e m s in t h e use of t h e atlas, t h o u g h . F o r e x a m p l e , F i g u r e 1 is n o t labeled or c a p t i o n e d , t h e r e are n o references

listed in t h e E n g l i s h v e r s i o n o f t h e t e x t , a n d w r o n g s y m b o l s a r e occasionally used, e.g. "Plate VI" should read "Plate VI"; the "VI" s y m b o l refers to a n e n t i r e V e n u s s p e c t r u m r a t h e r t h a n a p l a t e , or page, c o v e r i n g a 24-cm -1 region. I n T a b l e 1 t h e s y m b o l "2.3//z" is u s e d i n s t e a d o f 2.3/~. Still, t h e s e m i n o r errors c a n b e easily c i r c u m v e n t e d b y t h e i n t e r e s t e d r e a d e r a n d s h o u l d n o t cause a n y g r e a t concern. P e r h a p s t h e biggest p r o b l e m is in t h e i n t e r p r e t a t i o n of intensities. No v e r t i c a l scale is s h o w n a n d t h e i n t e n s i t i e s are p l o t t e d as relative. T h e p l o t s of t h e ratios, Q, of p l a n e t a r y s p e c t r a t o c o m p a r i s o n s p e c t r a (e.g., t h e S u n ) are difficult t o understand without considerable knowledge of t h e s p e c t r a . I n principle, Q s i m p l y r e p r e s e n t s t h e p l a n e t a r y s p e c t r u m w i t h effects o f t h e solar s p e c t r u m a n d tellurie s p e c t r u m t a k e n out, b u t , in p r a c t i c e , t h e different c o n d i t i o n s of o b s e r v a t i o n o f t h e p l a n e t a n d its c o m p a r i s o n s p e c t r u m (e.g., v a r i a t i o n s in air m a s s a n d t e r r e s t r i a l w a t e r vapor, Doppler broadening due to planetary r o t a t i o n , etc.) m a k e t h e d e r i v a t i o n of Q u n c e r t a i n . T h e r e m a y h e p a r t i c u l a r t r o u b l e in d e c i d i n g a t w h i c h frequencies a n d t o w h a t e x t e n t tellurie a b s o r p t i o n s m a y affect t h e v a l u e o f Q; a l t h o u g h some e x a m p l e s of t h i s p r o b l e m are g i v e n in t h e t e x t , t h e r e are m a n y s p e c t r a l regions n o t considered. I t w o u l d s e e m t h a t f u r t h e r efforts in assessing t h e effects of tellurie a b s o r p t i o n w o u l d h e l p a g r e a t deal in i n t e r p r e t i n g t h e s p e c t r a . To s u m m a r i z e , I believe t h e a t l a s is a n e c e s s a r y p a r t of a n y l i b r a r y c o n c e r n e d w i t h p l a n e t a r y research, b e c a u s e it c o n t a i n s u n d e r one c o v e r an e x t r a o r d i n a r y a m o u n t of significant d a t a for f u t u r e s t u d y a n d reference. BRIAN O'LEARY

Laboratory for Planetary Studies Cornell University Ithaca, New York, 14850 H a n d b o o k o f Astronautics. E d i t e d b y N. YA. KONDRAT'EV AND V. A. ODINTSOV. T r a n s l a t e d from Russian (and edited by R. Hardin). I s r a e l P r o g r a m for Scientific T r a n s l a t i o n s , J e r u s a l e m , for N A S A a n d N S F , 1968. viii + 224 p p . (Available as N A S A T T F-500.) P r i c e $3.00.

Handbook of Astronautics, w h i c h e m p h a s i z e s t h e m a n n e d flight a s p e c t s of a s t r o n a u t i c s , is an Israeli t r a n s l a t i o n (with v e r y m i n o r e d i t i n g ) of a R u s s i a n b o o k ; i t is w r i t t e n a t t h e level o f a 140